Merging upstream version 1.44.3.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

17 files changed, 7365 insertions, 0 deletions

diff --git a/fluent-bit/lib/librdkafka-2.1.0/src-cpp/CMakeLists.txt b/fluent-bit/lib/librdkafka-2.1.0/src-cpp/CMakeLists.txt
new file mode 100644
index 00000000..b0a6d51e
--- /dev/null
+++ b/fluent-bit/lib/librdkafka-2.1.0/src-cpp/CMakeLists.txt
@@ -0,0 +1,90 @@
+set(LIBVER 1)
+
+set(
+    sources
+    ConfImpl.cpp
+    ConsumerImpl.cpp
+    HandleImpl.cpp
+    HeadersImpl.cpp
+    KafkaConsumerImpl.cpp
+    MessageImpl.cpp
+    MetadataImpl.cpp
+    ProducerImpl.cpp
+    QueueImpl.cpp
+    RdKafka.cpp
+    TopicImpl.cpp
+    TopicPartitionImpl.cpp
+)
+
+if(RDKAFKA_BUILD_STATIC)
+  set(CMAKE_POSITION_INDEPENDENT_CODE ON)
+  set(RDKAFKA_BUILD_MODE STATIC)
+else()
+  set(RDKAFKA_BUILD_MODE SHARED)
+endif()
+
+add_library(rdkafka++ ${RDKAFKA_BUILD_MODE} ${sources})
+if(NOT RDKAFKA_BUILD_STATIC)
+  set_property(TARGET rdkafka++ PROPERTY SOVERSION ${LIBVER})
+endif()
+
+target_link_libraries(rdkafka++ PUBLIC rdkafka)
+
+# Support '#include <rdkafcpp.h>'
+target_include_directories(rdkafka++ PUBLIC "$<BUILD_INTERFACE:${CMAKE_CURRENT_LIST_DIR}>")
+if(NOT RDKAFKA_BUILD_STATIC)
+    target_compile_definitions(rdkafka++ PRIVATE LIBRDKAFKACPP_EXPORTS)
+endif()
+
+# Generate pkg-config file
+set(PKG_CONFIG_VERSION "${PROJECT_VERSION}")
+if(NOT RDKAFKA_BUILD_STATIC)
+  set(PKG_CONFIG_NAME "librdkafka++")
+  set(PKG_CONFIG_DESCRIPTION "The Apache Kafka C/C++ library")
+  set(PKG_CONFIG_REQUIRES "rdkafka")
+  set(PKG_CONFIG_CFLAGS "-I\${includedir}")
+  set(PKG_CONFIG_LIBS "-L\${libdir} -lrdkafka++")
+  set(PKG_CONFIG_LIBS_PRIVATE "-lrdkafka")
+  configure_file(
+    "../packaging/cmake/rdkafka.pc.in"
+    "${GENERATED_DIR}/rdkafka++.pc"
+    @ONLY
+  )
+  install(
+    FILES ${GENERATED_DIR}/rdkafka++.pc
+    DESTINATION "${CMAKE_INSTALL_LIBDIR}/pkgconfig"
+  )
+else()
+  set(PKG_CONFIG_NAME "librdkafka++-static")
+  set(PKG_CONFIG_DESCRIPTION "The Apache Kafka C/C++ library (static)")
+  set(PKG_CONFIG_REQUIRES "")
+  set(PKG_CONFIG_CFLAGS "-I\${includedir} -DLIBRDKAFKA_STATICLIB")
+  set(PKG_CONFIG_LIBS "-L\${libdir} \${libdir}/librdkafka++.a")
+  if(WIN32)
+    string(APPEND PKG_CONFIG_LIBS " -lws2_32 -lsecur32 -lcrypt32")
+  endif()
+
+  configure_file(
+    "../packaging/cmake/rdkafka.pc.in"
+    "${GENERATED_DIR}/rdkafka++-static.pc"
+    @ONLY
+  )
+  install(
+    FILES ${GENERATED_DIR}/rdkafka++-static.pc
+    DESTINATION "${CMAKE_INSTALL_LIBDIR}/pkgconfig"
+  )
+endif()
+
+install(
+    TARGETS rdkafka++
+    EXPORT "${targets_export_name}"
+    LIBRARY DESTINATION "${CMAKE_INSTALL_LIBDIR}"
+    ARCHIVE DESTINATION "${CMAKE_INSTALL_LIBDIR}"
+    RUNTIME DESTINATION "${CMAKE_INSTALL_BINDIR}"
+    INCLUDES DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}"
+)
+
+install(
+    FILES "rdkafkacpp.h"
+    DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}/librdkafka"
+)
diff --git a/fluent-bit/lib/librdkafka-2.1.0/src-cpp/ConfImpl.cpp b/fluent-bit/lib/librdkafka-2.1.0/src-cpp/ConfImpl.cpp
new file mode 100644
index 00000000..53d7b30c
--- /dev/null
+++ b/fluent-bit/lib/librdkafka-2.1.0/src-cpp/ConfImpl.cpp
@@ -0,0 +1,84 @@
+/*
+ * librdkafka - Apache Kafka C/C++ library
+ *
+ * Copyright (c) 2014 Magnus Edenhill
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <iostream>
+#include <string>
+#include <list>
+
+#include "rdkafkacpp_int.h"
+
+
+
+RdKafka::ConfImpl::ConfResult RdKafka::ConfImpl::set(const std::string &name,
+                                                     const std::string &value,
+                                                     std::string &errstr) {
+  rd_kafka_conf_res_t res;
+  char errbuf[512];
+
+  if (this->conf_type_ == CONF_GLOBAL)
+    res = rd_kafka_conf_set(this->rk_conf_, name.c_str(), value.c_str(), errbuf,
+                            sizeof(errbuf));
+  else
+    res = rd_kafka_topic_conf_set(this->rkt_conf_, name.c_str(), value.c_str(),
+                                  errbuf, sizeof(errbuf));
+
+  if (res != RD_KAFKA_CONF_OK)
+    errstr = errbuf;
+
+  return static_cast<Conf::ConfResult>(res);
+}
+
+
+std::list<std::string> *RdKafka::ConfImpl::dump() {
+  const char **arrc;
+  size_t cnt;
+  std::list<std::string> *arr;
+
+  if (rk_conf_)
+    arrc = rd_kafka_conf_dump(rk_conf_, &cnt);
+  else
+    arrc = rd_kafka_topic_conf_dump(rkt_conf_, &cnt);
+
+  arr = new std::list<std::string>();
+  for (int i = 0; i < static_cast<int>(cnt); i++)
+    arr->push_back(std::string(arrc[i]));
+
+  rd_kafka_conf_dump_free(arrc, cnt);
+  return arr;
+}
+
+RdKafka::Conf *RdKafka::Conf::create(ConfType type) {
+  ConfImpl *conf = new ConfImpl(type);
+
+  if (type == CONF_GLOBAL)
+    conf->rk_conf_ = rd_kafka_conf_new();
+  else
+    conf->rkt_conf_ = rd_kafka_topic_conf_new();
+
+  return conf;
+}
diff --git a/fluent-bit/lib/librdkafka-2.1.0/src-cpp/ConsumerImpl.cpp b/fluent-bit/lib/librdkafka-2.1.0/src-cpp/ConsumerImpl.cpp
new file mode 100644
index 00000000..b7f5e3b2
--- /dev/null
+++ b/fluent-bit/lib/librdkafka-2.1.0/src-cpp/ConsumerImpl.cpp
@@ -0,0 +1,244 @@
+/*
+ * librdkafka - Apache Kafka C/C++ library
+ *
+ * Copyright (c) 2014 Magnus Edenhill
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <iostream>
+#include <string>
+#include <list>
+#include <cerrno>
+
+#include "rdkafkacpp_int.h"
+
+RdKafka::Consumer::~Consumer() {
+}
+
+RdKafka::Consumer *RdKafka::Consumer::create(const RdKafka::Conf *conf,
+                                             std::string &errstr) {
+  char errbuf[512];
+  const RdKafka::ConfImpl *confimpl =
+      dynamic_cast<const RdKafka::ConfImpl *>(conf);
+  RdKafka::ConsumerImpl *rkc = new RdKafka::ConsumerImpl();
+  rd_kafka_conf_t *rk_conf   = NULL;
+
+  if (confimpl) {
+    if (!confimpl->rk_conf_) {
+      errstr = "Requires RdKafka::Conf::CONF_GLOBAL object";
+      delete rkc;
+      return NULL;
+    }
+
+    rkc->set_common_config(confimpl);
+
+    rk_conf = rd_kafka_conf_dup(confimpl->rk_conf_);
+  }
+
+  rd_kafka_t *rk;
+  if (!(rk =
+            rd_kafka_new(RD_KAFKA_CONSUMER, rk_conf, errbuf, sizeof(errbuf)))) {
+    errstr = errbuf;
+    // rd_kafka_new() takes ownership only if succeeds
+    if (rk_conf)
+      rd_kafka_conf_destroy(rk_conf);
+    delete rkc;
+    return NULL;
+  }
+
+  rkc->rk_ = rk;
+
+
+  return rkc;
+}
+
+int64_t RdKafka::Consumer::OffsetTail(int64_t offset) {
+  return RD_KAFKA_OFFSET_TAIL(offset);
+}
+
+RdKafka::ErrorCode RdKafka::ConsumerImpl::start(Topic *topic,
+                                                int32_t partition,
+                                                int64_t offset) {
+  RdKafka::TopicImpl *topicimpl = dynamic_cast<RdKafka::TopicImpl *>(topic);
+
+  if (rd_kafka_consume_start(topicimpl->rkt_, partition, offset) == -1)
+    return static_cast<RdKafka::ErrorCode>(rd_kafka_last_error());
+
+  return RdKafka::ERR_NO_ERROR;
+}
+
+
+RdKafka::ErrorCode RdKafka::ConsumerImpl::start(Topic *topic,
+                                                int32_t partition,
+                                                int64_t offset,
+                                                Queue *queue) {
+  RdKafka::TopicImpl *topicimpl = dynamic_cast<RdKafka::TopicImpl *>(topic);
+  RdKafka::QueueImpl *queueimpl = dynamic_cast<RdKafka::QueueImpl *>(queue);
+
+  if (rd_kafka_consume_start_queue(topicimpl->rkt_, partition, offset,
+                                   queueimpl->queue_) == -1)
+    return static_cast<RdKafka::ErrorCode>(rd_kafka_last_error());
+
+  return RdKafka::ERR_NO_ERROR;
+}
+
+
+RdKafka::ErrorCode RdKafka::ConsumerImpl::stop(Topic *topic,
+                                               int32_t partition) {
+  RdKafka::TopicImpl *topicimpl = dynamic_cast<RdKafka::TopicImpl *>(topic);
+
+  if (rd_kafka_consume_stop(topicimpl->rkt_, partition) == -1)
+    return static_cast<RdKafka::ErrorCode>(rd_kafka_last_error());
+
+  return RdKafka::ERR_NO_ERROR;
+}
+
+RdKafka::ErrorCode RdKafka::ConsumerImpl::seek(Topic *topic,
+                                               int32_t partition,
+                                               int64_t offset,
+                                               int timeout_ms) {
+  RdKafka::TopicImpl *topicimpl = dynamic_cast<RdKafka::TopicImpl *>(topic);
+
+  if (rd_kafka_seek(topicimpl->rkt_, partition, offset, timeout_ms) == -1)
+    return static_cast<RdKafka::ErrorCode>(rd_kafka_last_error());
+
+  return RdKafka::ERR_NO_ERROR;
+}
+
+RdKafka::Message *RdKafka::ConsumerImpl::consume(Topic *topic,
+                                                 int32_t partition,
+                                                 int timeout_ms) {
+  RdKafka::TopicImpl *topicimpl = dynamic_cast<RdKafka::TopicImpl *>(topic);
+  rd_kafka_message_t *rkmessage;
+
+  rkmessage = rd_kafka_consume(topicimpl->rkt_, partition, timeout_ms);
+  if (!rkmessage)
+    return new RdKafka::MessageImpl(
+        RD_KAFKA_CONSUMER, topic,
+        static_cast<RdKafka::ErrorCode>(rd_kafka_last_error()));
+
+  return new RdKafka::MessageImpl(RD_KAFKA_CONSUMER, topic, rkmessage);
+}
+
+namespace {
+/* Helper struct for `consume_callback'.
+ * Encapsulates the values we need in order to call `rd_kafka_consume_callback'
+ * and keep track of the C++ callback function and `opaque' value.
+ */
+struct ConsumerImplCallback {
+  ConsumerImplCallback(RdKafka::Topic *topic,
+                       RdKafka::ConsumeCb *cb,
+                       void *data) :
+      topic(topic), cb_cls(cb), cb_data(data) {
+  }
+  /* This function is the one we give to `rd_kafka_consume_callback', with
+   * the `opaque' pointer pointing to an instance of this struct, in which
+   * we can find the C++ callback and `cb_data'.
+   */
+  static void consume_cb_trampoline(rd_kafka_message_t *msg, void *opaque) {
+    ConsumerImplCallback *instance =
+        static_cast<ConsumerImplCallback *>(opaque);
+    RdKafka::MessageImpl message(RD_KAFKA_CONSUMER, instance->topic, msg,
+                                 false /*don't free*/);
+    instance->cb_cls->consume_cb(message, instance->cb_data);
+  }
+  RdKafka::Topic *topic;
+  RdKafka::ConsumeCb *cb_cls;
+  void *cb_data;
+};
+}  // namespace
+
+int RdKafka::ConsumerImpl::consume_callback(RdKafka::Topic *topic,
+                                            int32_t partition,
+                                            int timeout_ms,
+                                            RdKafka::ConsumeCb *consume_cb,
+                                            void *opaque) {
+  RdKafka::TopicImpl *topicimpl = static_cast<RdKafka::TopicImpl *>(topic);
+  ConsumerImplCallback context(topic, consume_cb, opaque);
+  return rd_kafka_consume_callback(topicimpl->rkt_, partition, timeout_ms,
+                                   &ConsumerImplCallback::consume_cb_trampoline,
+                                   &context);
+}
+
+
+RdKafka::Message *RdKafka::ConsumerImpl::consume(Queue *queue, int timeout_ms) {
+  RdKafka::QueueImpl *queueimpl = dynamic_cast<RdKafka::QueueImpl *>(queue);
+  rd_kafka_message_t *rkmessage;
+
+  rkmessage = rd_kafka_consume_queue(queueimpl->queue_, timeout_ms);
+  if (!rkmessage)
+    return new RdKafka::MessageImpl(
+        RD_KAFKA_CONSUMER, NULL,
+        static_cast<RdKafka::ErrorCode>(rd_kafka_last_error()));
+  /*
+   * Recover our Topic * from the topic conf's opaque field, which we
+   * set in RdKafka::Topic::create() for just this kind of situation.
+   */
+  void *opaque = rd_kafka_topic_opaque(rkmessage->rkt);
+  Topic *topic = static_cast<Topic *>(opaque);
+
+  return new RdKafka::MessageImpl(RD_KAFKA_CONSUMER, topic, rkmessage);
+}
+
+namespace {
+/* Helper struct for `consume_callback' with a Queue.
+ * Encapsulates the values we need in order to call `rd_kafka_consume_callback'
+ * and keep track of the C++ callback function and `opaque' value.
+ */
+struct ConsumerImplQueueCallback {
+  ConsumerImplQueueCallback(RdKafka::ConsumeCb *cb, void *data) :
+      cb_cls(cb), cb_data(data) {
+  }
+  /* This function is the one we give to `rd_kafka_consume_callback', with
+   * the `opaque' pointer pointing to an instance of this struct, in which
+   * we can find the C++ callback and `cb_data'.
+   */
+  static void consume_cb_trampoline(rd_kafka_message_t *msg, void *opaque) {
+    ConsumerImplQueueCallback *instance =
+        static_cast<ConsumerImplQueueCallback *>(opaque);
+    /*
+     * Recover our Topic * from the topic conf's opaque field, which we
+     * set in RdKafka::Topic::create() for just this kind of situation.
+     */
+    void *topic_opaque    = rd_kafka_topic_opaque(msg->rkt);
+    RdKafka::Topic *topic = static_cast<RdKafka::Topic *>(topic_opaque);
+    RdKafka::MessageImpl message(RD_KAFKA_CONSUMER, topic, msg,
+                                 false /*don't free*/);
+    instance->cb_cls->consume_cb(message, instance->cb_data);
+  }
+  RdKafka::ConsumeCb *cb_cls;
+  void *cb_data;
+};
+}  // namespace
+
+int RdKafka::ConsumerImpl::consume_callback(Queue *queue,
+                                            int timeout_ms,
+                                            RdKafka::ConsumeCb *consume_cb,
+                                            void *opaque) {
+  RdKafka::QueueImpl *queueimpl = dynamic_cast<RdKafka::QueueImpl *>(queue);
+  ConsumerImplQueueCallback context(consume_cb, opaque);
+  return rd_kafka_consume_callback_queue(
+      queueimpl->queue_, timeout_ms,
+      &ConsumerImplQueueCallback::consume_cb_trampoline, &context);
+}
diff --git a/fluent-bit/lib/librdkafka-2.1.0/src-cpp/HandleImpl.cpp b/fluent-bit/lib/librdkafka-2.1.0/src-cpp/HandleImpl.cpp
new file mode 100644
index 00000000..7aa2f293
--- /dev/null
+++ b/fluent-bit/lib/librdkafka-2.1.0/src-cpp/HandleImpl.cpp
@@ -0,0 +1,425 @@
+/*
+ * librdkafka - Apache Kafka C/C++ library
+ *
+ * Copyright (c) 2014 Magnus Edenhill
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <iostream>
+#include <string>
+#include <list>
+
+#include "rdkafkacpp_int.h"
+
+void RdKafka::consume_cb_trampoline(rd_kafka_message_t *msg, void *opaque) {
+  RdKafka::HandleImpl *handle = static_cast<RdKafka::HandleImpl *>(opaque);
+  RdKafka::Topic *topic = static_cast<Topic *>(rd_kafka_topic_opaque(msg->rkt));
+
+  RdKafka::MessageImpl message(RD_KAFKA_CONSUMER, topic, msg,
+                               false /*don't free*/);
+
+  handle->consume_cb_->consume_cb(message, opaque);
+}
+
+void RdKafka::log_cb_trampoline(const rd_kafka_t *rk,
+                                int level,
+                                const char *fac,
+                                const char *buf) {
+  if (!rk) {
+    rd_kafka_log_print(rk, level, fac, buf);
+    return;
+  }
+
+  void *opaque                = rd_kafka_opaque(rk);
+  RdKafka::HandleImpl *handle = static_cast<RdKafka::HandleImpl *>(opaque);
+
+  if (!handle->event_cb_) {
+    rd_kafka_log_print(rk, level, fac, buf);
+    return;
+  }
+
+  RdKafka::EventImpl event(RdKafka::Event::EVENT_LOG, RdKafka::ERR_NO_ERROR,
+                           static_cast<RdKafka::Event::Severity>(level), fac,
+                           buf);
+
+  handle->event_cb_->event_cb(event);
+}
+
+
+void RdKafka::error_cb_trampoline(rd_kafka_t *rk,
+                                  int err,
+                                  const char *reason,
+                                  void *opaque) {
+  RdKafka::HandleImpl *handle = static_cast<RdKafka::HandleImpl *>(opaque);
+  char errstr[512];
+  bool is_fatal = false;
+
+  if (err == RD_KAFKA_RESP_ERR__FATAL) {
+    /* Translate to underlying fatal error code and string */
+    err = rd_kafka_fatal_error(rk, errstr, sizeof(errstr));
+    if (err)
+      reason = errstr;
+    is_fatal = true;
+  }
+  RdKafka::EventImpl event(RdKafka::Event::EVENT_ERROR,
+                           static_cast<RdKafka::ErrorCode>(err),
+                           RdKafka::Event::EVENT_SEVERITY_ERROR, NULL, reason);
+  event.fatal_ = is_fatal;
+  handle->event_cb_->event_cb(event);
+}
+
+
+void RdKafka::throttle_cb_trampoline(rd_kafka_t *rk,
+                                     const char *broker_name,
+                                     int32_t broker_id,
+                                     int throttle_time_ms,
+                                     void *opaque) {
+  RdKafka::HandleImpl *handle = static_cast<RdKafka::HandleImpl *>(opaque);
+
+  RdKafka::EventImpl event(RdKafka::Event::EVENT_THROTTLE);
+  event.str_           = broker_name;
+  event.id_            = broker_id;
+  event.throttle_time_ = throttle_time_ms;
+
+  handle->event_cb_->event_cb(event);
+}
+
+
+int RdKafka::stats_cb_trampoline(rd_kafka_t *rk,
+                                 char *json,
+                                 size_t json_len,
+                                 void *opaque) {
+  RdKafka::HandleImpl *handle = static_cast<RdKafka::HandleImpl *>(opaque);
+
+  RdKafka::EventImpl event(RdKafka::Event::EVENT_STATS, RdKafka::ERR_NO_ERROR,
+                           RdKafka::Event::EVENT_SEVERITY_INFO, NULL, json);
+
+  handle->event_cb_->event_cb(event);
+
+  return 0;
+}
+
+
+int RdKafka::socket_cb_trampoline(int domain,
+                                  int type,
+                                  int protocol,
+                                  void *opaque) {
+  RdKafka::HandleImpl *handle = static_cast<RdKafka::HandleImpl *>(opaque);
+
+  return handle->socket_cb_->socket_cb(domain, type, protocol);
+}
+
+int RdKafka::open_cb_trampoline(const char *pathname,
+                                int flags,
+                                mode_t mode,
+                                void *opaque) {
+  RdKafka::HandleImpl *handle = static_cast<RdKafka::HandleImpl *>(opaque);
+
+  return handle->open_cb_->open_cb(pathname, flags, static_cast<int>(mode));
+}
+
+void RdKafka::oauthbearer_token_refresh_cb_trampoline(
+    rd_kafka_t *rk,
+    const char *oauthbearer_config,
+    void *opaque) {
+  RdKafka::HandleImpl *handle = static_cast<RdKafka::HandleImpl *>(opaque);
+
+  handle->oauthbearer_token_refresh_cb_->oauthbearer_token_refresh_cb(
+      handle, std::string(oauthbearer_config ? oauthbearer_config : ""));
+}
+
+
+int RdKafka::ssl_cert_verify_cb_trampoline(rd_kafka_t *rk,
+                                           const char *broker_name,
+                                           int32_t broker_id,
+                                           int *x509_error,
+                                           int depth,
+                                           const char *buf,
+                                           size_t size,
+                                           char *errstr,
+                                           size_t errstr_size,
+                                           void *opaque) {
+  RdKafka::HandleImpl *handle = static_cast<RdKafka::HandleImpl *>(opaque);
+  std::string errbuf;
+
+  bool res = 0 != handle->ssl_cert_verify_cb_->ssl_cert_verify_cb(
+                      std::string(broker_name), broker_id, x509_error, depth,
+                      buf, size, errbuf);
+
+  if (res)
+    return (int)res;
+
+  size_t errlen =
+      errbuf.size() > errstr_size - 1 ? errstr_size - 1 : errbuf.size();
+
+  memcpy(errstr, errbuf.c_str(), errlen);
+  if (errstr_size > 0)
+    errstr[errlen] = '\0';
+
+  return (int)res;
+}
+
+
+RdKafka::ErrorCode RdKafka::HandleImpl::metadata(bool all_topics,
+                                                 const Topic *only_rkt,
+                                                 Metadata **metadatap,
+                                                 int timeout_ms) {
+  const rd_kafka_metadata_t *cmetadatap = NULL;
+
+  rd_kafka_topic_t *topic =
+      only_rkt ? static_cast<const TopicImpl *>(only_rkt)->rkt_ : NULL;
+
+  const rd_kafka_resp_err_t rc =
+      rd_kafka_metadata(rk_, all_topics, topic, &cmetadatap, timeout_ms);
+
+  *metadatap = (rc == RD_KAFKA_RESP_ERR_NO_ERROR)
+                   ? new RdKafka::MetadataImpl(cmetadatap)
+                   : NULL;
+
+  return static_cast<RdKafka::ErrorCode>(rc);
+}
+
+/**
+ * Convert a list of C partitions to C++ partitions
+ */
+static void c_parts_to_partitions(
+    const rd_kafka_topic_partition_list_t *c_parts,
+    std::vector<RdKafka::TopicPartition *> &partitions) {
+  partitions.resize(c_parts->cnt);
+  for (int i = 0; i < c_parts->cnt; i++)
+    partitions[i] = new RdKafka::TopicPartitionImpl(&c_parts->elems[i]);
+}
+
+static void free_partition_vector(std::vector<RdKafka::TopicPartition *> &v) {
+  for (unsigned int i = 0; i < v.size(); i++)
+    delete v[i];
+  v.clear();
+}
+
+void RdKafka::rebalance_cb_trampoline(
+    rd_kafka_t *rk,
+    rd_kafka_resp_err_t err,
+    rd_kafka_topic_partition_list_t *c_partitions,
+    void *opaque) {
+  RdKafka::HandleImpl *handle = static_cast<RdKafka::HandleImpl *>(opaque);
+  std::vector<RdKafka::TopicPartition *> partitions;
+
+  c_parts_to_partitions(c_partitions, partitions);
+
+  handle->rebalance_cb_->rebalance_cb(
+      dynamic_cast<RdKafka::KafkaConsumer *>(handle),
+      static_cast<RdKafka::ErrorCode>(err), partitions);
+
+  free_partition_vector(partitions);
+}
+
+
+void RdKafka::offset_commit_cb_trampoline0(
+    rd_kafka_t *rk,
+    rd_kafka_resp_err_t err,
+    rd_kafka_topic_partition_list_t *c_offsets,
+    void *opaque) {
+  OffsetCommitCb *cb = static_cast<RdKafka::OffsetCommitCb *>(opaque);
+  std::vector<RdKafka::TopicPartition *> offsets;
+
+  if (c_offsets)
+    c_parts_to_partitions(c_offsets, offsets);
+
+  cb->offset_commit_cb(static_cast<RdKafka::ErrorCode>(err), offsets);
+
+  free_partition_vector(offsets);
+}
+
+static void offset_commit_cb_trampoline(
+    rd_kafka_t *rk,
+    rd_kafka_resp_err_t err,
+    rd_kafka_topic_partition_list_t *c_offsets,
+    void *opaque) {
+  RdKafka::HandleImpl *handle = static_cast<RdKafka::HandleImpl *>(opaque);
+  RdKafka::offset_commit_cb_trampoline0(rk, err, c_offsets,
+                                        handle->offset_commit_cb_);
+}
+
+
+void RdKafka::HandleImpl::set_common_config(const RdKafka::ConfImpl *confimpl) {
+  rd_kafka_conf_set_opaque(confimpl->rk_conf_, this);
+
+  if (confimpl->event_cb_) {
+    rd_kafka_conf_set_log_cb(confimpl->rk_conf_, RdKafka::log_cb_trampoline);
+    rd_kafka_conf_set_error_cb(confimpl->rk_conf_,
+                               RdKafka::error_cb_trampoline);
+    rd_kafka_conf_set_throttle_cb(confimpl->rk_conf_,
+                                  RdKafka::throttle_cb_trampoline);
+    rd_kafka_conf_set_stats_cb(confimpl->rk_conf_,
+                               RdKafka::stats_cb_trampoline);
+    event_cb_ = confimpl->event_cb_;
+  }
+
+  if (confimpl->oauthbearer_token_refresh_cb_) {
+    rd_kafka_conf_set_oauthbearer_token_refresh_cb(
+        confimpl->rk_conf_, RdKafka::oauthbearer_token_refresh_cb_trampoline);
+    oauthbearer_token_refresh_cb_ = confimpl->oauthbearer_token_refresh_cb_;
+  }
+
+  if (confimpl->socket_cb_) {
+    rd_kafka_conf_set_socket_cb(confimpl->rk_conf_,
+                                RdKafka::socket_cb_trampoline);
+    socket_cb_ = confimpl->socket_cb_;
+  }
+
+  if (confimpl->ssl_cert_verify_cb_) {
+    rd_kafka_conf_set_ssl_cert_verify_cb(
+        confimpl->rk_conf_, RdKafka::ssl_cert_verify_cb_trampoline);
+    ssl_cert_verify_cb_ = confimpl->ssl_cert_verify_cb_;
+  }
+
+  if (confimpl->open_cb_) {
+#ifndef _WIN32
+    rd_kafka_conf_set_open_cb(confimpl->rk_conf_, RdKafka::open_cb_trampoline);
+    open_cb_ = confimpl->open_cb_;
+#endif
+  }
+
+  if (confimpl->rebalance_cb_) {
+    rd_kafka_conf_set_rebalance_cb(confimpl->rk_conf_,
+                                   RdKafka::rebalance_cb_trampoline);
+    rebalance_cb_ = confimpl->rebalance_cb_;
+  }
+
+  if (confimpl->offset_commit_cb_) {
+    rd_kafka_conf_set_offset_commit_cb(confimpl->rk_conf_,
+                                       offset_commit_cb_trampoline);
+    offset_commit_cb_ = confimpl->offset_commit_cb_;
+  }
+
+  if (confimpl->consume_cb_) {
+    rd_kafka_conf_set_consume_cb(confimpl->rk_conf_,
+                                 RdKafka::consume_cb_trampoline);
+    consume_cb_ = confimpl->consume_cb_;
+  }
+}
+
+
+RdKafka::ErrorCode RdKafka::HandleImpl::pause(
+    std::vector<RdKafka::TopicPartition *> &partitions) {
+  rd_kafka_topic_partition_list_t *c_parts;
+  rd_kafka_resp_err_t err;
+
+  c_parts = partitions_to_c_parts(partitions);
+
+  err = rd_kafka_pause_partitions(rk_, c_parts);
+
+  if (!err)
+    update_partitions_from_c_parts(partitions, c_parts);
+
+  rd_kafka_topic_partition_list_destroy(c_parts);
+
+  return static_cast<RdKafka::ErrorCode>(err);
+}
+
+
+RdKafka::ErrorCode RdKafka::HandleImpl::resume(
+    std::vector<RdKafka::TopicPartition *> &partitions) {
+  rd_kafka_topic_partition_list_t *c_parts;
+  rd_kafka_resp_err_t err;
+
+  c_parts = partitions_to_c_parts(partitions);
+
+  err = rd_kafka_resume_partitions(rk_, c_parts);
+
+  if (!err)
+    update_partitions_from_c_parts(partitions, c_parts);
+
+  rd_kafka_topic_partition_list_destroy(c_parts);
+
+  return static_cast<RdKafka::ErrorCode>(err);
+}
+
+RdKafka::Queue *RdKafka::HandleImpl::get_partition_queue(
+    const TopicPartition *part) {
+  rd_kafka_queue_t *rkqu;
+  rkqu = rd_kafka_queue_get_partition(rk_, part->topic().c_str(),
+                                      part->partition());
+
+  if (rkqu == NULL)
+    return NULL;
+
+  return new QueueImpl(rkqu);
+}
+
+RdKafka::ErrorCode RdKafka::HandleImpl::set_log_queue(RdKafka::Queue *queue) {
+  rd_kafka_queue_t *rkqu = NULL;
+  if (queue) {
+    QueueImpl *queueimpl = dynamic_cast<QueueImpl *>(queue);
+    rkqu                 = queueimpl->queue_;
+  }
+  return static_cast<RdKafka::ErrorCode>(rd_kafka_set_log_queue(rk_, rkqu));
+}
+
+namespace RdKafka {
+
+rd_kafka_topic_partition_list_t *partitions_to_c_parts(
+    const std::vector<RdKafka::TopicPartition *> &partitions) {
+  rd_kafka_topic_partition_list_t *c_parts;
+
+  c_parts = rd_kafka_topic_partition_list_new((int)partitions.size());
+
+  for (unsigned int i = 0; i < partitions.size(); i++) {
+    const RdKafka::TopicPartitionImpl *tpi =
+        dynamic_cast<const RdKafka::TopicPartitionImpl *>(partitions[i]);
+    rd_kafka_topic_partition_t *rktpar = rd_kafka_topic_partition_list_add(
+        c_parts, tpi->topic_.c_str(), tpi->partition_);
+    rktpar->offset = tpi->offset_;
+    if (tpi->leader_epoch_ != -1)
+      rd_kafka_topic_partition_set_leader_epoch(rktpar, tpi->leader_epoch_);
+  }
+
+  return c_parts;
+}
+
+
+/**
+ * @brief Update the application provided 'partitions' with info from 'c_parts'
+ */
+void update_partitions_from_c_parts(
+    std::vector<RdKafka::TopicPartition *> &partitions,
+    const rd_kafka_topic_partition_list_t *c_parts) {
+  for (int i = 0; i < c_parts->cnt; i++) {
+    rd_kafka_topic_partition_t *p = &c_parts->elems[i];
+
+    /* Find corresponding C++ entry */
+    for (unsigned int j = 0; j < partitions.size(); j++) {
+      RdKafka::TopicPartitionImpl *pp =
+          dynamic_cast<RdKafka::TopicPartitionImpl *>(partitions[j]);
+      if (!strcmp(p->topic, pp->topic_.c_str()) &&
+          p->partition == pp->partition_) {
+        pp->offset_       = p->offset;
+        pp->err_          = static_cast<RdKafka::ErrorCode>(p->err);
+        pp->leader_epoch_ = rd_kafka_topic_partition_get_leader_epoch(p);
+      }
+    }
+  }
+}
+
+}  // namespace RdKafka
diff --git a/fluent-bit/lib/librdkafka-2.1.0/src-cpp/HeadersImpl.cpp b/fluent-bit/lib/librdkafka-2.1.0/src-cpp/HeadersImpl.cpp
new file mode 100644
index 00000000..b567ef36
--- /dev/null
+++ b/fluent-bit/lib/librdkafka-2.1.0/src-cpp/HeadersImpl.cpp
@@ -0,0 +1,48 @@
+/*
+ * librdkafka - Apache Kafka C/C++ library
+ *
+ * Copyright (c) 2014 Magnus Edenhill
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <iostream>
+#include <string>
+#include <list>
+#include <cerrno>
+
+#include "rdkafkacpp_int.h"
+
+RdKafka::Headers *RdKafka::Headers::create() {
+  return new RdKafka::HeadersImpl();
+}
+
+RdKafka::Headers *RdKafka::Headers::create(const std::vector<Header> &headers) {
+  if (headers.size() > 0)
+    return new RdKafka::HeadersImpl(headers);
+  else
+    return new RdKafka::HeadersImpl();
+}
+
+RdKafka::Headers::~Headers() {
+}
diff --git a/fluent-bit/lib/librdkafka-2.1.0/src-cpp/KafkaConsumerImpl.cpp b/fluent-bit/lib/librdkafka-2.1.0/src-cpp/KafkaConsumerImpl.cpp
new file mode 100644
index 00000000..6f3b81c7
--- /dev/null
+++ b/fluent-bit/lib/librdkafka-2.1.0/src-cpp/KafkaConsumerImpl.cpp
@@ -0,0 +1,296 @@
+/*
+ * librdkafka - Apache Kafka C/C++ library
+ *
+ * Copyright (c) 2015 Magnus Edenhill
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <string>
+#include <vector>
+
+#include "rdkafkacpp_int.h"
+
+RdKafka::KafkaConsumer::~KafkaConsumer() {
+}
+
+RdKafka::KafkaConsumer *RdKafka::KafkaConsumer::create(
+    const RdKafka::Conf *conf,
+    std::string &errstr) {
+  char errbuf[512];
+  const RdKafka::ConfImpl *confimpl =
+      dynamic_cast<const RdKafka::ConfImpl *>(conf);
+  RdKafka::KafkaConsumerImpl *rkc = new RdKafka::KafkaConsumerImpl();
+  rd_kafka_conf_t *rk_conf        = NULL;
+  size_t grlen;
+
+  if (!confimpl || !confimpl->rk_conf_) {
+    errstr = "Requires RdKafka::Conf::CONF_GLOBAL object";
+    delete rkc;
+    return NULL;
+  }
+
+  if (rd_kafka_conf_get(confimpl->rk_conf_, "group.id", NULL, &grlen) !=
+          RD_KAFKA_CONF_OK ||
+      grlen <= 1 /* terminating null only */) {
+    errstr = "\"group.id\" must be configured";
+    delete rkc;
+    return NULL;
+  }
+
+  rkc->set_common_config(confimpl);
+
+  rk_conf = rd_kafka_conf_dup(confimpl->rk_conf_);
+
+  rd_kafka_t *rk;
+  if (!(rk =
+            rd_kafka_new(RD_KAFKA_CONSUMER, rk_conf, errbuf, sizeof(errbuf)))) {
+    errstr = errbuf;
+    // rd_kafka_new() takes ownership only if succeeds
+    rd_kafka_conf_destroy(rk_conf);
+    delete rkc;
+    return NULL;
+  }
+
+  rkc->rk_ = rk;
+
+  /* Redirect handle queue to cgrp's queue to provide a single queue point */
+  rd_kafka_poll_set_consumer(rk);
+
+  return rkc;
+}
+
+
+
+RdKafka::ErrorCode RdKafka::KafkaConsumerImpl::subscribe(
+    const std::vector<std::string> &topics) {
+  rd_kafka_topic_partition_list_t *c_topics;
+  rd_kafka_resp_err_t err;
+
+  c_topics = rd_kafka_topic_partition_list_new((int)topics.size());
+
+  for (unsigned int i = 0; i < topics.size(); i++)
+    rd_kafka_topic_partition_list_add(c_topics, topics[i].c_str(),
+                                      RD_KAFKA_PARTITION_UA);
+
+  err = rd_kafka_subscribe(rk_, c_topics);
+
+  rd_kafka_topic_partition_list_destroy(c_topics);
+
+  return static_cast<RdKafka::ErrorCode>(err);
+}
+
+
+
+RdKafka::ErrorCode RdKafka::KafkaConsumerImpl::unsubscribe() {
+  return static_cast<RdKafka::ErrorCode>(rd_kafka_unsubscribe(this->rk_));
+}
+
+RdKafka::Message *RdKafka::KafkaConsumerImpl::consume(int timeout_ms) {
+  rd_kafka_message_t *rkmessage;
+
+  rkmessage = rd_kafka_consumer_poll(this->rk_, timeout_ms);
+
+  if (!rkmessage)
+    return new RdKafka::MessageImpl(RD_KAFKA_CONSUMER, NULL,
+                                    RdKafka::ERR__TIMED_OUT);
+
+  return new RdKafka::MessageImpl(RD_KAFKA_CONSUMER, rkmessage);
+}
+
+
+
+RdKafka::ErrorCode RdKafka::KafkaConsumerImpl::assignment(
+    std::vector<RdKafka::TopicPartition *> &partitions) {
+  rd_kafka_topic_partition_list_t *c_parts;
+  rd_kafka_resp_err_t err;
+
+  if ((err = rd_kafka_assignment(rk_, &c_parts)))
+    return static_cast<RdKafka::ErrorCode>(err);
+
+  partitions.resize(c_parts->cnt);
+
+  for (int i = 0; i < c_parts->cnt; i++)
+    partitions[i] = new RdKafka::TopicPartitionImpl(&c_parts->elems[i]);
+
+  rd_kafka_topic_partition_list_destroy(c_parts);
+
+  return RdKafka::ERR_NO_ERROR;
+}
+
+
+
+bool RdKafka::KafkaConsumerImpl::assignment_lost() {
+  return rd_kafka_assignment_lost(rk_) ? true : false;
+}
+
+
+
+RdKafka::ErrorCode RdKafka::KafkaConsumerImpl::subscription(
+    std::vector<std::string> &topics) {
+  rd_kafka_topic_partition_list_t *c_topics;
+  rd_kafka_resp_err_t err;
+
+  if ((err = rd_kafka_subscription(rk_, &c_topics)))
+    return static_cast<RdKafka::ErrorCode>(err);
+
+  topics.resize(c_topics->cnt);
+  for (int i = 0; i < c_topics->cnt; i++)
+    topics[i] = std::string(c_topics->elems[i].topic);
+
+  rd_kafka_topic_partition_list_destroy(c_topics);
+
+  return RdKafka::ERR_NO_ERROR;
+}
+
+
+RdKafka::ErrorCode RdKafka::KafkaConsumerImpl::assign(
+    const std::vector<TopicPartition *> &partitions) {
+  rd_kafka_topic_partition_list_t *c_parts;
+  rd_kafka_resp_err_t err;
+
+  c_parts = partitions_to_c_parts(partitions);
+
+  err = rd_kafka_assign(rk_, c_parts);
+
+  rd_kafka_topic_partition_list_destroy(c_parts);
+  return static_cast<RdKafka::ErrorCode>(err);
+}
+
+
+RdKafka::ErrorCode RdKafka::KafkaConsumerImpl::unassign() {
+  return static_cast<RdKafka::ErrorCode>(rd_kafka_assign(rk_, NULL));
+}
+
+
+RdKafka::Error *RdKafka::KafkaConsumerImpl::incremental_assign(
+    const std::vector<TopicPartition *> &partitions) {
+  rd_kafka_topic_partition_list_t *c_parts;
+  rd_kafka_error_t *c_error;
+
+  c_parts = partitions_to_c_parts(partitions);
+  c_error = rd_kafka_incremental_assign(rk_, c_parts);
+  rd_kafka_topic_partition_list_destroy(c_parts);
+
+  if (c_error)
+    return new ErrorImpl(c_error);
+
+  return NULL;
+}
+
+
+RdKafka::Error *RdKafka::KafkaConsumerImpl::incremental_unassign(
+    const std::vector<TopicPartition *> &partitions) {
+  rd_kafka_topic_partition_list_t *c_parts;
+  rd_kafka_error_t *c_error;
+
+  c_parts = partitions_to_c_parts(partitions);
+  c_error = rd_kafka_incremental_unassign(rk_, c_parts);
+  rd_kafka_topic_partition_list_destroy(c_parts);
+
+  if (c_error)
+    return new ErrorImpl(c_error);
+
+  return NULL;
+}
+
+
+RdKafka::ErrorCode RdKafka::KafkaConsumerImpl::committed(
+    std::vector<RdKafka::TopicPartition *> &partitions,
+    int timeout_ms) {
+  rd_kafka_topic_partition_list_t *c_parts;
+  rd_kafka_resp_err_t err;
+
+  c_parts = partitions_to_c_parts(partitions);
+
+  err = rd_kafka_committed(rk_, c_parts, timeout_ms);
+
+  if (!err) {
+    update_partitions_from_c_parts(partitions, c_parts);
+  }
+
+  rd_kafka_topic_partition_list_destroy(c_parts);
+
+  return static_cast<RdKafka::ErrorCode>(err);
+}
+
+
+RdKafka::ErrorCode RdKafka::KafkaConsumerImpl::position(
+    std::vector<RdKafka::TopicPartition *> &partitions) {
+  rd_kafka_topic_partition_list_t *c_parts;
+  rd_kafka_resp_err_t err;
+
+  c_parts = partitions_to_c_parts(partitions);
+
+  err = rd_kafka_position(rk_, c_parts);
+
+  if (!err) {
+    update_partitions_from_c_parts(partitions, c_parts);
+  }
+
+  rd_kafka_topic_partition_list_destroy(c_parts);
+
+  return static_cast<RdKafka::ErrorCode>(err);
+}
+
+
+RdKafka::ErrorCode RdKafka::KafkaConsumerImpl::seek(
+    const RdKafka::TopicPartition &partition,
+    int timeout_ms) {
+  const RdKafka::TopicPartitionImpl *p =
+      dynamic_cast<const RdKafka::TopicPartitionImpl *>(&partition);
+  rd_kafka_topic_t *rkt;
+
+  if (!(rkt = rd_kafka_topic_new(rk_, p->topic_.c_str(), NULL)))
+    return static_cast<RdKafka::ErrorCode>(rd_kafka_last_error());
+
+  /* FIXME: Use a C API that takes a topic_partition_list_t instead */
+  RdKafka::ErrorCode err = static_cast<RdKafka::ErrorCode>(
+      rd_kafka_seek(rkt, p->partition_, p->offset_, timeout_ms));
+
+  rd_kafka_topic_destroy(rkt);
+
+  return err;
+}
+
+
+
+RdKafka::ErrorCode RdKafka::KafkaConsumerImpl::close() {
+  return static_cast<RdKafka::ErrorCode>(rd_kafka_consumer_close(rk_));
+}
+
+
+RdKafka::Error *RdKafka::KafkaConsumerImpl::close(Queue *queue) {
+  QueueImpl *queueimpl = dynamic_cast<QueueImpl *>(queue);
+  rd_kafka_error_t *c_error;
+
+  c_error = rd_kafka_consumer_close_queue(rk_, queueimpl->queue_);
+  if (c_error)
+    return new ErrorImpl(c_error);
+
+  return NULL;
+}
+
+
+RdKafka::ConsumerGroupMetadata::~ConsumerGroupMetadata() {
+}
diff --git a/fluent-bit/lib/librdkafka-2.1.0/src-cpp/Makefile b/fluent-bit/lib/librdkafka-2.1.0/src-cpp/Makefile
new file mode 100644
index 00000000..78ecb31f
--- /dev/null
+++ b/fluent-bit/lib/librdkafka-2.1.0/src-cpp/Makefile
@@ -0,0 +1,55 @@
+PKGNAME=	librdkafka
+LIBNAME=	librdkafka++
+LIBVER=		1
+
+CXXSRCS=	RdKafka.cpp ConfImpl.cpp HandleImpl.cpp \
+		ConsumerImpl.cpp ProducerImpl.cpp KafkaConsumerImpl.cpp \
+		TopicImpl.cpp TopicPartitionImpl.cpp MessageImpl.cpp \
+		HeadersImpl.cpp QueueImpl.cpp MetadataImpl.cpp
+
+HDRS=		rdkafkacpp.h
+
+OBJS=		$(CXXSRCS:%.cpp=%.o)
+
+
+
+all: lib check
+
+# No linker script/symbol hiding for C++ library
+DISABLE_LDS=y
+
+MKL_NO_SELFCONTAINED_STATIC_LIB=y
+include ../mklove/Makefile.base
+
+# Use C++ compiler as linker rather than the default C compiler
+CC_LD=$(CXX)
+
+# OSX and Cygwin requires linking required libraries
+ifeq ($(_UNAME_S),Darwin)
+	FWD_LINKING_REQ=y
+endif
+ifeq ($(_UNAME_S),AIX)
+	FWD_LINKING_REQ=y
+endif
+ifeq ($(shell uname -o 2>/dev/null),Cygwin)
+	FWD_LINKING_REQ=y
+endif
+
+# Ignore previously defined library dependencies for the C library,
+# we'll get those dependencies through the C library linkage.
+LIBS := -L../src -lrdkafka
+MKL_PKGCONFIG_REQUIRES_PRIVATE := rdkafka
+MKL_PKGCONFIG_REQUIRES := rdkafka
+
+CHECK_FILES+= $(LIBFILENAME) $(LIBNAME).a
+
+
+file-check: lib
+check: file-check
+
+install: lib-install
+uninstall: lib-uninstall
+
+clean: lib-clean
+
+-include $(DEPS)
diff --git a/fluent-bit/lib/librdkafka-2.1.0/src-cpp/MessageImpl.cpp b/fluent-bit/lib/librdkafka-2.1.0/src-cpp/MessageImpl.cpp
new file mode 100644
index 00000000..c6d83150
--- /dev/null
+++ b/fluent-bit/lib/librdkafka-2.1.0/src-cpp/MessageImpl.cpp
@@ -0,0 +1,38 @@
+/*
+ * librdkafka - Apache Kafka C/C++ library
+ *
+ * Copyright (c) 2014 Magnus Edenhill
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <iostream>
+#include <string>
+#include <list>
+#include <cerrno>
+
+#include "rdkafkacpp_int.h"
+
+
+RdKafka::Message::~Message() {
+}
diff --git a/fluent-bit/lib/librdkafka-2.1.0/src-cpp/MetadataImpl.cpp b/fluent-bit/lib/librdkafka-2.1.0/src-cpp/MetadataImpl.cpp
new file mode 100644
index 00000000..62cbf904
--- /dev/null
+++ b/fluent-bit/lib/librdkafka-2.1.0/src-cpp/MetadataImpl.cpp
@@ -0,0 +1,170 @@
+/*
+ * librdkafka - Apache Kafka C/C++ library
+ *
+ * Copyright (c) 2014 Magnus Edenhill
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "rdkafkacpp_int.h"
+
+using namespace RdKafka;
+
+BrokerMetadata::~BrokerMetadata() {
+}
+PartitionMetadata::~PartitionMetadata() {
+}
+TopicMetadata::~TopicMetadata() {
+}
+Metadata::~Metadata() {
+}
+
+
+/**
+ * Metadata: Broker information handler implementation
+ */
+class BrokerMetadataImpl : public BrokerMetadata {
+ public:
+  BrokerMetadataImpl(const rd_kafka_metadata_broker_t *broker_metadata) :
+      broker_metadata_(broker_metadata), host_(broker_metadata->host) {
+  }
+
+  int32_t id() const {
+    return broker_metadata_->id;
+  }
+
+  std::string host() const {
+    return host_;
+  }
+  int port() const {
+    return broker_metadata_->port;
+  }
+
+  virtual ~BrokerMetadataImpl() {
+  }
+
+ private:
+  const rd_kafka_metadata_broker_t *broker_metadata_;
+  const std::string host_;
+};
+
+/**
+ * Metadata: Partition information handler
+ */
+class PartitionMetadataImpl : public PartitionMetadata {
+ public:
+  // @TODO too much memory copy? maybe we should create a new vector class that
+  // read directly from C arrays?
+  // @TODO use auto_ptr?
+  PartitionMetadataImpl(
+      const rd_kafka_metadata_partition_t *partition_metadata) :
+      partition_metadata_(partition_metadata) {
+    replicas_.reserve(partition_metadata->replica_cnt);
+    for (int i = 0; i < partition_metadata->replica_cnt; ++i)
+      replicas_.push_back(partition_metadata->replicas[i]);
+
+    isrs_.reserve(partition_metadata->isr_cnt);
+    for (int i = 0; i < partition_metadata->isr_cnt; ++i)
+      isrs_.push_back(partition_metadata->isrs[i]);
+  }
+
+  int32_t id() const {
+    return partition_metadata_->id;
+  }
+  int32_t leader() const {
+    return partition_metadata_->leader;
+  }
+  ErrorCode err() const {
+    return static_cast<ErrorCode>(partition_metadata_->err);
+  }
+
+  const std::vector<int32_t> *replicas() const {
+    return &replicas_;
+  }
+  const std::vector<int32_t> *isrs() const {
+    return &isrs_;
+  }
+
+  ~PartitionMetadataImpl() {
+  }
+
+ private:
+  const rd_kafka_metadata_partition_t *partition_metadata_;
+  std::vector<int32_t> replicas_, isrs_;
+};
+
+/**
+ * Metadata: Topic information handler
+ */
+class TopicMetadataImpl : public TopicMetadata {
+ public:
+  TopicMetadataImpl(const rd_kafka_metadata_topic_t *topic_metadata) :
+      topic_metadata_(topic_metadata), topic_(topic_metadata->topic) {
+    partitions_.reserve(topic_metadata->partition_cnt);
+    for (int i = 0; i < topic_metadata->partition_cnt; ++i)
+      partitions_.push_back(
+          new PartitionMetadataImpl(&topic_metadata->partitions[i]));
+  }
+
+  ~TopicMetadataImpl() {
+    for (size_t i = 0; i < partitions_.size(); ++i)
+      delete partitions_[i];
+  }
+
+  std::string topic() const {
+    return topic_;
+  }
+  const std::vector<const PartitionMetadata *> *partitions() const {
+    return &partitions_;
+  }
+  ErrorCode err() const {
+    return static_cast<ErrorCode>(topic_metadata_->err);
+  }
+
+ private:
+  const rd_kafka_metadata_topic_t *topic_metadata_;
+  const std::string topic_;
+  std::vector<const PartitionMetadata *> partitions_;
+};
+
+MetadataImpl::MetadataImpl(const rd_kafka_metadata_t *metadata) :
+    metadata_(metadata) {
+  brokers_.reserve(metadata->broker_cnt);
+  for (int i = 0; i < metadata->broker_cnt; ++i)
+    brokers_.push_back(new BrokerMetadataImpl(&metadata->brokers[i]));
+
+  topics_.reserve(metadata->topic_cnt);
+  for (int i = 0; i < metadata->topic_cnt; ++i)
+    topics_.push_back(new TopicMetadataImpl(&metadata->topics[i]));
+}
+
+MetadataImpl::~MetadataImpl() {
+  for (size_t i = 0; i < brokers_.size(); ++i)
+    delete brokers_[i];
+  for (size_t i = 0; i < topics_.size(); ++i)
+    delete topics_[i];
+
+
+  if (metadata_)
+    rd_kafka_metadata_destroy(metadata_);
+}
diff --git a/fluent-bit/lib/librdkafka-2.1.0/src-cpp/ProducerImpl.cpp b/fluent-bit/lib/librdkafka-2.1.0/src-cpp/ProducerImpl.cpp
new file mode 100644
index 00000000..8300dfb3
--- /dev/null
+++ b/fluent-bit/lib/librdkafka-2.1.0/src-cpp/ProducerImpl.cpp
@@ -0,0 +1,197 @@
+/*
+ * librdkafka - Apache Kafka C/C++ library
+ *
+ * Copyright (c) 2014 Magnus Edenhill
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <iostream>
+#include <string>
+#include <list>
+#include <cerrno>
+
+#include "rdkafkacpp_int.h"
+
+
+RdKafka::Producer::~Producer() {
+}
+
+static void dr_msg_cb_trampoline(rd_kafka_t *rk,
+                                 const rd_kafka_message_t *rkmessage,
+                                 void *opaque) {
+  RdKafka::HandleImpl *handle = static_cast<RdKafka::HandleImpl *>(opaque);
+  RdKafka::MessageImpl message(RD_KAFKA_PRODUCER, NULL,
+                               (rd_kafka_message_t *)rkmessage, false);
+  handle->dr_cb_->dr_cb(message);
+}
+
+
+
+RdKafka::Producer *RdKafka::Producer::create(const RdKafka::Conf *conf,
+                                             std::string &errstr) {
+  char errbuf[512];
+  const RdKafka::ConfImpl *confimpl =
+      dynamic_cast<const RdKafka::ConfImpl *>(conf);
+  RdKafka::ProducerImpl *rkp = new RdKafka::ProducerImpl();
+  rd_kafka_conf_t *rk_conf   = NULL;
+
+  if (confimpl) {
+    if (!confimpl->rk_conf_) {
+      errstr = "Requires RdKafka::Conf::CONF_GLOBAL object";
+      delete rkp;
+      return NULL;
+    }
+
+    rkp->set_common_config(confimpl);
+
+    rk_conf = rd_kafka_conf_dup(confimpl->rk_conf_);
+
+    if (confimpl->dr_cb_) {
+      rd_kafka_conf_set_dr_msg_cb(rk_conf, dr_msg_cb_trampoline);
+      rkp->dr_cb_ = confimpl->dr_cb_;
+    }
+  }
+
+
+  rd_kafka_t *rk;
+  if (!(rk =
+            rd_kafka_new(RD_KAFKA_PRODUCER, rk_conf, errbuf, sizeof(errbuf)))) {
+    errstr = errbuf;
+    // rd_kafka_new() takes ownership only if succeeds
+    if (rk_conf)
+      rd_kafka_conf_destroy(rk_conf);
+    delete rkp;
+    return NULL;
+  }
+
+  rkp->rk_ = rk;
+
+  return rkp;
+}
+
+
+RdKafka::ErrorCode RdKafka::ProducerImpl::produce(RdKafka::Topic *topic,
+                                                  int32_t partition,
+                                                  int msgflags,
+                                                  void *payload,
+                                                  size_t len,
+                                                  const std::string *key,
+                                                  void *msg_opaque) {
+  RdKafka::TopicImpl *topicimpl = dynamic_cast<RdKafka::TopicImpl *>(topic);
+
+  if (rd_kafka_produce(topicimpl->rkt_, partition, msgflags, payload, len,
+                       key ? key->c_str() : NULL, key ? key->size() : 0,
+                       msg_opaque) == -1)
+    return static_cast<RdKafka::ErrorCode>(rd_kafka_last_error());
+
+  return RdKafka::ERR_NO_ERROR;
+}
+
+
+RdKafka::ErrorCode RdKafka::ProducerImpl::produce(RdKafka::Topic *topic,
+                                                  int32_t partition,
+                                                  int msgflags,
+                                                  void *payload,
+                                                  size_t len,
+                                                  const void *key,
+                                                  size_t key_len,
+                                                  void *msg_opaque) {
+  RdKafka::TopicImpl *topicimpl = dynamic_cast<RdKafka::TopicImpl *>(topic);
+
+  if (rd_kafka_produce(topicimpl->rkt_, partition, msgflags, payload, len, key,
+                       key_len, msg_opaque) == -1)
+    return static_cast<RdKafka::ErrorCode>(rd_kafka_last_error());
+
+  return RdKafka::ERR_NO_ERROR;
+}
+
+
+RdKafka::ErrorCode RdKafka::ProducerImpl::produce(
+    RdKafka::Topic *topic,
+    int32_t partition,
+    const std::vector<char> *payload,
+    const std::vector<char> *key,
+    void *msg_opaque) {
+  RdKafka::TopicImpl *topicimpl = dynamic_cast<RdKafka::TopicImpl *>(topic);
+
+  if (rd_kafka_produce(topicimpl->rkt_, partition, RD_KAFKA_MSG_F_COPY,
+                       payload ? (void *)&(*payload)[0] : NULL,
+                       payload ? payload->size() : 0, key ? &(*key)[0] : NULL,
+                       key ? key->size() : 0, msg_opaque) == -1)
+    return static_cast<RdKafka::ErrorCode>(rd_kafka_last_error());
+
+  return RdKafka::ERR_NO_ERROR;
+}
+
+RdKafka::ErrorCode RdKafka::ProducerImpl::produce(const std::string topic_name,
+                                                  int32_t partition,
+                                                  int msgflags,
+                                                  void *payload,
+                                                  size_t len,
+                                                  const void *key,
+                                                  size_t key_len,
+                                                  int64_t timestamp,
+                                                  void *msg_opaque) {
+  return static_cast<RdKafka::ErrorCode>(rd_kafka_producev(
+      rk_, RD_KAFKA_V_TOPIC(topic_name.c_str()),
+      RD_KAFKA_V_PARTITION(partition), RD_KAFKA_V_MSGFLAGS(msgflags),
+      RD_KAFKA_V_VALUE(payload, len), RD_KAFKA_V_KEY(key, key_len),
+      RD_KAFKA_V_TIMESTAMP(timestamp), RD_KAFKA_V_OPAQUE(msg_opaque),
+      RD_KAFKA_V_END));
+}
+
+RdKafka::ErrorCode RdKafka::ProducerImpl::produce(const std::string topic_name,
+                                                  int32_t partition,
+                                                  int msgflags,
+                                                  void *payload,
+                                                  size_t len,
+                                                  const void *key,
+                                                  size_t key_len,
+                                                  int64_t timestamp,
+                                                  RdKafka::Headers *headers,
+                                                  void *msg_opaque) {
+  rd_kafka_headers_t *hdrs          = NULL;
+  RdKafka::HeadersImpl *headersimpl = NULL;
+  rd_kafka_resp_err_t err;
+
+  if (headers) {
+    headersimpl = static_cast<RdKafka::HeadersImpl *>(headers);
+    hdrs        = headersimpl->c_ptr();
+  }
+
+  err = rd_kafka_producev(
+      rk_, RD_KAFKA_V_TOPIC(topic_name.c_str()),
+      RD_KAFKA_V_PARTITION(partition), RD_KAFKA_V_MSGFLAGS(msgflags),
+      RD_KAFKA_V_VALUE(payload, len), RD_KAFKA_V_KEY(key, key_len),
+      RD_KAFKA_V_TIMESTAMP(timestamp), RD_KAFKA_V_OPAQUE(msg_opaque),
+      RD_KAFKA_V_HEADERS(hdrs), RD_KAFKA_V_END);
+
+  if (!err && headersimpl) {
+    /* A successful producev() call will destroy the C headers. */
+    headersimpl->c_headers_destroyed();
+    delete headers;
+  }
+
+  return static_cast<RdKafka::ErrorCode>(err);
+}
diff --git a/fluent-bit/lib/librdkafka-2.1.0/src-cpp/QueueImpl.cpp b/fluent-bit/lib/librdkafka-2.1.0/src-cpp/QueueImpl.cpp
new file mode 100644
index 00000000..19ebce9d
--- /dev/null
+++ b/fluent-bit/lib/librdkafka-2.1.0/src-cpp/QueueImpl.cpp
@@ -0,0 +1,70 @@
+/*
+ * librdkafka - Apache Kafka C/C++ library
+ *
+ * Copyright (c) 2014 Magnus Edenhill
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <cerrno>
+
+#include "rdkafkacpp_int.h"
+
+RdKafka::Queue::~Queue() {
+}
+
+RdKafka::Queue *RdKafka::Queue::create(Handle *base) {
+  return new RdKafka::QueueImpl(
+      rd_kafka_queue_new(dynamic_cast<HandleImpl *>(base)->rk_));
+}
+
+RdKafka::ErrorCode RdKafka::QueueImpl::forward(Queue *queue) {
+  if (!queue) {
+    rd_kafka_queue_forward(queue_, NULL);
+  } else {
+    QueueImpl *queueimpl = dynamic_cast<QueueImpl *>(queue);
+    rd_kafka_queue_forward(queue_, queueimpl->queue_);
+  }
+  return RdKafka::ERR_NO_ERROR;
+}
+
+RdKafka::Message *RdKafka::QueueImpl::consume(int timeout_ms) {
+  rd_kafka_message_t *rkmessage;
+  rkmessage = rd_kafka_consume_queue(queue_, timeout_ms);
+
+  if (!rkmessage)
+    return new RdKafka::MessageImpl(RD_KAFKA_CONSUMER, NULL,
+                                    RdKafka::ERR__TIMED_OUT);
+
+  return new RdKafka::MessageImpl(RD_KAFKA_CONSUMER, rkmessage);
+}
+
+int RdKafka::QueueImpl::poll(int timeout_ms) {
+  return rd_kafka_queue_poll_callback(queue_, timeout_ms);
+}
+
+void RdKafka::QueueImpl::io_event_enable(int fd,
+                                         const void *payload,
+                                         size_t size) {
+  rd_kafka_queue_io_event_enable(queue_, fd, payload, size);
+}
diff --git a/fluent-bit/lib/librdkafka-2.1.0/src-cpp/README.md b/fluent-bit/lib/librdkafka-2.1.0/src-cpp/README.md
new file mode 100644
index 00000000..a4845894
--- /dev/null
+++ b/fluent-bit/lib/librdkafka-2.1.0/src-cpp/README.md
@@ -0,0 +1,16 @@
+librdkafka C++ interface
+========================
+
+**See rdkafkacpp.h for the public C++ API**
+
+
+
+Maintainer notes for the C++ interface:
+
+ * The public C++ interface (rdkafkacpp.h) does not include the
+   public C interface (rdkafka.h) in any way, this means that all
+   constants, flags, etc, must be kept in sync manually between the two
+   header files.
+   A regression test should be implemented that checks this is true.
+
+ * The public C++ interface is provided using pure virtual abstract classes.
diff --git a/fluent-bit/lib/librdkafka-2.1.0/src-cpp/RdKafka.cpp b/fluent-bit/lib/librdkafka-2.1.0/src-cpp/RdKafka.cpp
new file mode 100644
index 00000000..b6cb33c2
--- /dev/null
+++ b/fluent-bit/lib/librdkafka-2.1.0/src-cpp/RdKafka.cpp
@@ -0,0 +1,59 @@
+/*
+ * librdkafka - Apache Kafka C/C++ library
+ *
+ * Copyright (c) 2014 Magnus Edenhill
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <string>
+
+#include "rdkafkacpp_int.h"
+
+int RdKafka::version() {
+  return rd_kafka_version();
+}
+
+std::string RdKafka::version_str() {
+  return std::string(rd_kafka_version_str());
+}
+
+std::string RdKafka::get_debug_contexts() {
+  return std::string(RD_KAFKA_DEBUG_CONTEXTS);
+}
+
+std::string RdKafka::err2str(RdKafka::ErrorCode err) {
+  return std::string(rd_kafka_err2str(static_cast<rd_kafka_resp_err_t>(err)));
+}
+
+int RdKafka::wait_destroyed(int timeout_ms) {
+  return rd_kafka_wait_destroyed(timeout_ms);
+}
+
+void *RdKafka::mem_malloc(size_t size) {
+  return rd_kafka_mem_malloc(NULL, size);
+}
+
+void RdKafka::mem_free(void *ptr) {
+  rd_kafka_mem_free(NULL, ptr);
+}
diff --git a/fluent-bit/lib/librdkafka-2.1.0/src-cpp/TopicImpl.cpp b/fluent-bit/lib/librdkafka-2.1.0/src-cpp/TopicImpl.cpp
new file mode 100644
index 00000000..bf9734df
--- /dev/null
+++ b/fluent-bit/lib/librdkafka-2.1.0/src-cpp/TopicImpl.cpp
@@ -0,0 +1,124 @@
+/*
+ * librdkafka - Apache Kafka C/C++ library
+ *
+ * Copyright (c) 2014 Magnus Edenhill
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <iostream>
+#include <string>
+#include <list>
+#include <cerrno>
+
+#include "rdkafkacpp_int.h"
+
+const int32_t RdKafka::Topic::PARTITION_UA = RD_KAFKA_PARTITION_UA;
+
+const int64_t RdKafka::Topic::OFFSET_BEGINNING = RD_KAFKA_OFFSET_BEGINNING;
+
+const int64_t RdKafka::Topic::OFFSET_END = RD_KAFKA_OFFSET_END;
+
+const int64_t RdKafka::Topic::OFFSET_STORED = RD_KAFKA_OFFSET_STORED;
+
+const int64_t RdKafka::Topic::OFFSET_INVALID = RD_KAFKA_OFFSET_INVALID;
+
+RdKafka::Topic::~Topic() {
+}
+
+static int32_t partitioner_cb_trampoline(const rd_kafka_topic_t *rkt,
+                                         const void *keydata,
+                                         size_t keylen,
+                                         int32_t partition_cnt,
+                                         void *rkt_opaque,
+                                         void *msg_opaque) {
+  RdKafka::TopicImpl *topicimpl = static_cast<RdKafka::TopicImpl *>(rkt_opaque);
+  std::string key(static_cast<const char *>(keydata), keylen);
+  return topicimpl->partitioner_cb_->partitioner_cb(topicimpl, &key,
+                                                    partition_cnt, msg_opaque);
+}
+
+static int32_t partitioner_kp_cb_trampoline(const rd_kafka_topic_t *rkt,
+                                            const void *keydata,
+                                            size_t keylen,
+                                            int32_t partition_cnt,
+                                            void *rkt_opaque,
+                                            void *msg_opaque) {
+  RdKafka::TopicImpl *topicimpl = static_cast<RdKafka::TopicImpl *>(rkt_opaque);
+  return topicimpl->partitioner_kp_cb_->partitioner_cb(
+      topicimpl, keydata, keylen, partition_cnt, msg_opaque);
+}
+
+
+
+RdKafka::Topic *RdKafka::Topic::create(Handle *base,
+                                       const std::string &topic_str,
+                                       const Conf *conf,
+                                       std::string &errstr) {
+  const RdKafka::ConfImpl *confimpl =
+      static_cast<const RdKafka::ConfImpl *>(conf);
+  rd_kafka_topic_t *rkt;
+  rd_kafka_topic_conf_t *rkt_conf;
+  rd_kafka_t *rk = dynamic_cast<HandleImpl *>(base)->rk_;
+
+  RdKafka::TopicImpl *topic = new RdKafka::TopicImpl();
+
+  if (!confimpl) {
+    /* Reuse default topic config, but we need our own copy to
+     * set the topic opaque. */
+    rkt_conf = rd_kafka_default_topic_conf_dup(rk);
+  } else {
+    /* Make a copy of conf struct to allow Conf reuse. */
+    rkt_conf = rd_kafka_topic_conf_dup(confimpl->rkt_conf_);
+  }
+
+  /* Set topic opaque to the topic so that we can reach our topic object
+   * from whatever callbacks get registered.
+   * The application itself will not need these opaques since their
+   * callbacks are class based. */
+  rd_kafka_topic_conf_set_opaque(rkt_conf, static_cast<void *>(topic));
+
+  if (confimpl) {
+    if (confimpl->partitioner_cb_) {
+      rd_kafka_topic_conf_set_partitioner_cb(rkt_conf,
+                                             partitioner_cb_trampoline);
+      topic->partitioner_cb_ = confimpl->partitioner_cb_;
+    } else if (confimpl->partitioner_kp_cb_) {
+      rd_kafka_topic_conf_set_partitioner_cb(rkt_conf,
+                                             partitioner_kp_cb_trampoline);
+      topic->partitioner_kp_cb_ = confimpl->partitioner_kp_cb_;
+    }
+  }
+
+
+  if (!(rkt = rd_kafka_topic_new(rk, topic_str.c_str(), rkt_conf))) {
+    errstr = rd_kafka_err2str(rd_kafka_last_error());
+    delete topic;
+    rd_kafka_topic_conf_destroy(rkt_conf);
+    return NULL;
+  }
+
+  topic->rkt_ = rkt;
+
+  return topic;
+}
diff --git a/fluent-bit/lib/librdkafka-2.1.0/src-cpp/TopicPartitionImpl.cpp b/fluent-bit/lib/librdkafka-2.1.0/src-cpp/TopicPartitionImpl.cpp
new file mode 100644
index 00000000..90ef820b
--- /dev/null
+++ b/fluent-bit/lib/librdkafka-2.1.0/src-cpp/TopicPartitionImpl.cpp
@@ -0,0 +1,57 @@
+/*
+ * librdkafka - Apache Kafka C/C++ library
+ *
+ * Copyright (c) 2015 Magnus Edenhill
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <iostream>
+#include <string>
+#include <vector>
+
+#include "rdkafkacpp_int.h"
+
+RdKafka::TopicPartition::~TopicPartition() {
+}
+
+RdKafka::TopicPartition *RdKafka::TopicPartition::create(
+    const std::string &topic,
+    int partition) {
+  return new TopicPartitionImpl(topic, partition);
+}
+
+RdKafka::TopicPartition *RdKafka::TopicPartition::create(
+    const std::string &topic,
+    int partition,
+    int64_t offset) {
+  return new TopicPartitionImpl(topic, partition, offset);
+}
+
+void RdKafka::TopicPartition::destroy(
+    std::vector<TopicPartition *> &partitions) {
+  for (std::vector<TopicPartition *>::iterator it = partitions.begin();
+       it != partitions.end(); ++it)
+    delete (*it);
+  partitions.clear();
+}
diff --git a/fluent-bit/lib/librdkafka-2.1.0/src-cpp/rdkafkacpp.h b/fluent-bit/lib/librdkafka-2.1.0/src-cpp/rdkafkacpp.h
new file mode 100644
index 00000000..1df1043c
--- /dev/null
+++ b/fluent-bit/lib/librdkafka-2.1.0/src-cpp/rdkafkacpp.h
@@ -0,0 +1,3764 @@
+/*
+ * librdkafka - Apache Kafka C/C++ library
+ *
+ * Copyright (c) 2014-2022 Magnus Edenhill
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef _RDKAFKACPP_H_
+#define _RDKAFKACPP_H_
+
+/**
+ * @file rdkafkacpp.h
+ * @brief Apache Kafka C/C++ consumer and producer client library.
+ *
+ * rdkafkacpp.h contains the public C++ API for librdkafka.
+ * The API is documented in this file as comments prefixing the class,
+ * function, type, enum, define, etc.
+ * For more information, see the C interface in rdkafka.h and read the
+ * manual in INTRODUCTION.md.
+ * The C++ interface is STD C++ '03 compliant and adheres to the
+ * Google C++ Style Guide.
+
+ * @sa For the C interface see rdkafka.h
+ *
+ * @tableofcontents
+ */
+
+/**@cond NO_DOC*/
+#include <string>
+#include <list>
+#include <vector>
+#include <cstdlib>
+#include <cstring>
+#include <stdint.h>
+#include <sys/types.h>
+
+#ifdef _WIN32
+#ifndef ssize_t
+#ifndef _BASETSD_H_
+#include <basetsd.h>
+#endif
+#ifndef _SSIZE_T_DEFINED
+#define _SSIZE_T_DEFINED
+typedef SSIZE_T ssize_t;
+#endif
+#endif
+#undef RD_EXPORT
+#ifdef LIBRDKAFKA_STATICLIB
+#define RD_EXPORT
+#else
+#ifdef LIBRDKAFKACPP_EXPORTS
+#define RD_EXPORT __declspec(dllexport)
+#else
+#define RD_EXPORT __declspec(dllimport)
+#endif
+#endif
+#else
+#define RD_EXPORT
+#endif
+
+/**@endcond*/
+
+extern "C" {
+/* Forward declarations */
+struct rd_kafka_s;
+struct rd_kafka_topic_s;
+struct rd_kafka_message_s;
+struct rd_kafka_conf_s;
+struct rd_kafka_topic_conf_s;
+}
+
+namespace RdKafka {
+
+/**
+ * @name Miscellaneous APIs
+ * @{
+ */
+
+/**
+ * @brief librdkafka version
+ *
+ * Interpreted as hex \c MM.mm.rr.xx:
+ *  - MM = Major
+ *  - mm = minor
+ *  - rr = revision
+ *  - xx = pre-release id (0xff is the final release)
+ *
+ * E.g.: \c 0x000801ff = 0.8.1
+ *
+ * @remark This value should only be used during compile time,
+ *         for runtime checks of version use RdKafka::version()
+ */
+#define RD_KAFKA_VERSION 0x020100ff
+
+/**
+ * @brief Returns the librdkafka version as integer.
+ *
+ * @sa See RD_KAFKA_VERSION for how to parse the integer format.
+ */
+RD_EXPORT
+int version();
+
+/**
+ * @brief Returns the librdkafka version as string.
+ */
+RD_EXPORT
+std::string version_str();
+
+/**
+ * @brief Returns a CSV list of the supported debug contexts
+ *        for use with Conf::Set("debug", ..).
+ */
+RD_EXPORT
+std::string get_debug_contexts();
+
+/**
+ * @brief Wait for all rd_kafka_t objects to be destroyed.
+ *
+ * @returns 0 if all kafka objects are now destroyed, or -1 if the
+ * timeout was reached.
+ * Since RdKafka handle deletion is an asynch operation the
+ * \p wait_destroyed() function can be used for applications where
+ * a clean shutdown is required.
+ */
+RD_EXPORT
+int wait_destroyed(int timeout_ms);
+
+/**
+ * @brief Allocate memory using the same allocator librdkafka uses.
+ *
+ * This is typically an abstraction for the malloc(3) call and makes sure
+ * the application can use the same memory allocator as librdkafka for
+ * allocating pointers that are used by librdkafka.
+ *
+ * @remark Memory allocated by mem_malloc() must be freed using
+ *         mem_free().
+ */
+RD_EXPORT
+void *mem_malloc(size_t size);
+
+/**
+ * @brief Free pointer returned by librdkafka
+ *
+ * This is typically an abstraction for the free(3) call and makes sure
+ * the application can use the same memory allocator as librdkafka for
+ * freeing pointers returned by librdkafka.
+ *
+ * In standard setups it is usually not necessary to use this interface
+ * rather than the free(3) function.
+ *
+ * @remark mem_free() must only be used for pointers returned by APIs
+ *         that explicitly mention using this function for freeing.
+ */
+RD_EXPORT
+void mem_free(void *ptr);
+
+/**@}*/
+
+
+
+/**
+ * @name Constants, errors, types
+ * @{
+ *
+ *
+ */
+
+/**
+ * @brief Error codes.
+ *
+ * The negative error codes delimited by two underscores
+ * (\c _ERR__..) denotes errors internal to librdkafka and are
+ * displayed as \c \"Local: \<error string..\>\", while the error codes
+ * delimited by a single underscore (\c ERR_..) denote broker
+ * errors and are displayed as \c \"Broker: \<error string..\>\".
+ *
+ * @sa Use RdKafka::err2str() to translate an error code a human readable string
+ */
+enum ErrorCode {
+  /* Internal errors to rdkafka: */
+  /** Begin internal error codes */
+  ERR__BEGIN = -200,
+  /** Received message is incorrect */
+  ERR__BAD_MSG = -199,
+  /** Bad/unknown compression */
+  ERR__BAD_COMPRESSION = -198,
+  /** Broker is going away */
+  ERR__DESTROY = -197,
+  /** Generic failure */
+  ERR__FAIL = -196,
+  /** Broker transport failure */
+  ERR__TRANSPORT = -195,
+  /** Critical system resource */
+  ERR__CRIT_SYS_RESOURCE = -194,
+  /** Failed to resolve broker */
+  ERR__RESOLVE = -193,
+  /** Produced message timed out*/
+  ERR__MSG_TIMED_OUT = -192,
+  /** Reached the end of the topic+partition queue on
+   *  the broker. Not really an error.
+   *  This event is disabled by default,
+   *  see the `enable.partition.eof` configuration property. */
+  ERR__PARTITION_EOF = -191,
+  /** Permanent: Partition does not exist in cluster. */
+  ERR__UNKNOWN_PARTITION = -190,
+  /** File or filesystem error */
+  ERR__FS = -189,
+  /** Permanent: Topic does not exist in cluster. */
+  ERR__UNKNOWN_TOPIC = -188,
+  /** All broker connections are down. */
+  ERR__ALL_BROKERS_DOWN = -187,
+  /** Invalid argument, or invalid configuration */
+  ERR__INVALID_ARG = -186,
+  /** Operation timed out */
+  ERR__TIMED_OUT = -185,
+  /** Queue is full */
+  ERR__QUEUE_FULL = -184,
+  /** ISR count < required.acks */
+  ERR__ISR_INSUFF = -183,
+  /** Broker node update */
+  ERR__NODE_UPDATE = -182,
+  /** SSL error */
+  ERR__SSL = -181,
+  /** Waiting for coordinator to become available. */
+  ERR__WAIT_COORD = -180,
+  /** Unknown client group */
+  ERR__UNKNOWN_GROUP = -179,
+  /** Operation in progress */
+  ERR__IN_PROGRESS = -178,
+  /** Previous operation in progress, wait for it to finish. */
+  ERR__PREV_IN_PROGRESS = -177,
+  /** This operation would interfere with an existing subscription */
+  ERR__EXISTING_SUBSCRIPTION = -176,
+  /** Assigned partitions (rebalance_cb) */
+  ERR__ASSIGN_PARTITIONS = -175,
+  /** Revoked partitions (rebalance_cb) */
+  ERR__REVOKE_PARTITIONS = -174,
+  /** Conflicting use */
+  ERR__CONFLICT = -173,
+  /** Wrong state */
+  ERR__STATE = -172,
+  /** Unknown protocol */
+  ERR__UNKNOWN_PROTOCOL = -171,
+  /** Not implemented */
+  ERR__NOT_IMPLEMENTED = -170,
+  /** Authentication failure*/
+  ERR__AUTHENTICATION = -169,
+  /** No stored offset */
+  ERR__NO_OFFSET = -168,
+  /** Outdated */
+  ERR__OUTDATED = -167,
+  /** Timed out in queue */
+  ERR__TIMED_OUT_QUEUE = -166,
+  /** Feature not supported by broker */
+  ERR__UNSUPPORTED_FEATURE = -165,
+  /** Awaiting cache update */
+  ERR__WAIT_CACHE = -164,
+  /** Operation interrupted */
+  ERR__INTR = -163,
+  /** Key serialization error */
+  ERR__KEY_SERIALIZATION = -162,
+  /** Value serialization error */
+  ERR__VALUE_SERIALIZATION = -161,
+  /** Key deserialization error */
+  ERR__KEY_DESERIALIZATION = -160,
+  /** Value deserialization error */
+  ERR__VALUE_DESERIALIZATION = -159,
+  /** Partial response */
+  ERR__PARTIAL = -158,
+  /** Modification attempted on read-only object */
+  ERR__READ_ONLY = -157,
+  /** No such entry / item not found */
+  ERR__NOENT = -156,
+  /** Read underflow */
+  ERR__UNDERFLOW = -155,
+  /** Invalid type */
+  ERR__INVALID_TYPE = -154,
+  /** Retry operation */
+  ERR__RETRY = -153,
+  /** Purged in queue */
+  ERR__PURGE_QUEUE = -152,
+  /** Purged in flight */
+  ERR__PURGE_INFLIGHT = -151,
+  /** Fatal error: see RdKafka::Handle::fatal_error() */
+  ERR__FATAL = -150,
+  /** Inconsistent state */
+  ERR__INCONSISTENT = -149,
+  /** Gap-less ordering would not be guaranteed if proceeding */
+  ERR__GAPLESS_GUARANTEE = -148,
+  /** Maximum poll interval exceeded */
+  ERR__MAX_POLL_EXCEEDED = -147,
+  /** Unknown broker */
+  ERR__UNKNOWN_BROKER = -146,
+  /** Functionality not configured */
+  ERR__NOT_CONFIGURED = -145,
+  /** Instance has been fenced */
+  ERR__FENCED = -144,
+  /** Application generated error */
+  ERR__APPLICATION = -143,
+  /** Assignment lost */
+  ERR__ASSIGNMENT_LOST = -142,
+  /** No operation performed */
+  ERR__NOOP = -141,
+  /** No offset to automatically reset to */
+  ERR__AUTO_OFFSET_RESET = -140,
+  /** Partition log truncation detected */
+  ERR__LOG_TRUNCATION = -139,
+
+  /** End internal error codes */
+  ERR__END = -100,
+
+  /* Kafka broker errors: */
+  /** Unknown broker error */
+  ERR_UNKNOWN = -1,
+  /** Success */
+  ERR_NO_ERROR = 0,
+  /** Offset out of range */
+  ERR_OFFSET_OUT_OF_RANGE = 1,
+  /** Invalid message */
+  ERR_INVALID_MSG = 2,
+  /** Unknown topic or partition */
+  ERR_UNKNOWN_TOPIC_OR_PART = 3,
+  /** Invalid message size */
+  ERR_INVALID_MSG_SIZE = 4,
+  /** Leader not available */
+  ERR_LEADER_NOT_AVAILABLE = 5,
+  /** Not leader for partition */
+  ERR_NOT_LEADER_FOR_PARTITION = 6,
+  /** Request timed out */
+  ERR_REQUEST_TIMED_OUT = 7,
+  /** Broker not available */
+  ERR_BROKER_NOT_AVAILABLE = 8,
+  /** Replica not available */
+  ERR_REPLICA_NOT_AVAILABLE = 9,
+  /** Message size too large */
+  ERR_MSG_SIZE_TOO_LARGE = 10,
+  /** StaleControllerEpochCode */
+  ERR_STALE_CTRL_EPOCH = 11,
+  /** Offset metadata string too large */
+  ERR_OFFSET_METADATA_TOO_LARGE = 12,
+  /** Broker disconnected before response received */
+  ERR_NETWORK_EXCEPTION = 13,
+  /** Coordinator load in progress */
+  ERR_COORDINATOR_LOAD_IN_PROGRESS = 14,
+/** Group coordinator load in progress */
+#define ERR_GROUP_LOAD_IN_PROGRESS ERR_COORDINATOR_LOAD_IN_PROGRESS
+  /** Coordinator not available */
+  ERR_COORDINATOR_NOT_AVAILABLE = 15,
+/** Group coordinator not available */
+#define ERR_GROUP_COORDINATOR_NOT_AVAILABLE ERR_COORDINATOR_NOT_AVAILABLE
+  /** Not coordinator */
+  ERR_NOT_COORDINATOR = 16,
+/** Not coordinator for group */
+#define ERR_NOT_COORDINATOR_FOR_GROUP ERR_NOT_COORDINATOR
+  /** Invalid topic */
+  ERR_TOPIC_EXCEPTION = 17,
+  /** Message batch larger than configured server segment size */
+  ERR_RECORD_LIST_TOO_LARGE = 18,
+  /** Not enough in-sync replicas */
+  ERR_NOT_ENOUGH_REPLICAS = 19,
+  /** Message(s) written to insufficient number of in-sync replicas */
+  ERR_NOT_ENOUGH_REPLICAS_AFTER_APPEND = 20,
+  /** Invalid required acks value */
+  ERR_INVALID_REQUIRED_ACKS = 21,
+  /** Specified group generation id is not valid */
+  ERR_ILLEGAL_GENERATION = 22,
+  /** Inconsistent group protocol */
+  ERR_INCONSISTENT_GROUP_PROTOCOL = 23,
+  /** Invalid group.id */
+  ERR_INVALID_GROUP_ID = 24,
+  /** Unknown member */
+  ERR_UNKNOWN_MEMBER_ID = 25,
+  /** Invalid session timeout */
+  ERR_INVALID_SESSION_TIMEOUT = 26,
+  /** Group rebalance in progress */
+  ERR_REBALANCE_IN_PROGRESS = 27,
+  /** Commit offset data size is not valid */
+  ERR_INVALID_COMMIT_OFFSET_SIZE = 28,
+  /** Topic authorization failed */
+  ERR_TOPIC_AUTHORIZATION_FAILED = 29,
+  /** Group authorization failed */
+  ERR_GROUP_AUTHORIZATION_FAILED = 30,
+  /** Cluster authorization failed */
+  ERR_CLUSTER_AUTHORIZATION_FAILED = 31,
+  /** Invalid timestamp */
+  ERR_INVALID_TIMESTAMP = 32,
+  /** Unsupported SASL mechanism */
+  ERR_UNSUPPORTED_SASL_MECHANISM = 33,
+  /** Illegal SASL state */
+  ERR_ILLEGAL_SASL_STATE = 34,
+  /** Unuspported version */
+  ERR_UNSUPPORTED_VERSION = 35,
+  /** Topic already exists */
+  ERR_TOPIC_ALREADY_EXISTS = 36,
+  /** Invalid number of partitions */
+  ERR_INVALID_PARTITIONS = 37,
+  /** Invalid replication factor */
+  ERR_INVALID_REPLICATION_FACTOR = 38,
+  /** Invalid replica assignment */
+  ERR_INVALID_REPLICA_ASSIGNMENT = 39,
+  /** Invalid config */
+  ERR_INVALID_CONFIG = 40,
+  /** Not controller for cluster */
+  ERR_NOT_CONTROLLER = 41,
+  /** Invalid request */
+  ERR_INVALID_REQUEST = 42,
+  /** Message format on broker does not support request */
+  ERR_UNSUPPORTED_FOR_MESSAGE_FORMAT = 43,
+  /** Policy violation */
+  ERR_POLICY_VIOLATION = 44,
+  /** Broker received an out of order sequence number */
+  ERR_OUT_OF_ORDER_SEQUENCE_NUMBER = 45,
+  /** Broker received a duplicate sequence number */
+  ERR_DUPLICATE_SEQUENCE_NUMBER = 46,
+  /** Producer attempted an operation with an old epoch */
+  ERR_INVALID_PRODUCER_EPOCH = 47,
+  /** Producer attempted a transactional operation in an invalid state */
+  ERR_INVALID_TXN_STATE = 48,
+  /** Producer attempted to use a producer id which is not
+   *  currently assigned to its transactional id */
+  ERR_INVALID_PRODUCER_ID_MAPPING = 49,
+  /** Transaction timeout is larger than the maximum
+   *  value allowed by the broker's max.transaction.timeout.ms */
+  ERR_INVALID_TRANSACTION_TIMEOUT = 50,
+  /** Producer attempted to update a transaction while another
+   *  concurrent operation on the same transaction was ongoing */
+  ERR_CONCURRENT_TRANSACTIONS = 51,
+  /** Indicates that the transaction coordinator sending a
+   *  WriteTxnMarker is no longer the current coordinator for a
+   *  given producer */
+  ERR_TRANSACTION_COORDINATOR_FENCED = 52,
+  /** Transactional Id authorization failed */
+  ERR_TRANSACTIONAL_ID_AUTHORIZATION_FAILED = 53,
+  /** Security features are disabled */
+  ERR_SECURITY_DISABLED = 54,
+  /** Operation not attempted */
+  ERR_OPERATION_NOT_ATTEMPTED = 55,
+  /** Disk error when trying to access log file on the disk */
+  ERR_KAFKA_STORAGE_ERROR = 56,
+  /** The user-specified log directory is not found in the broker config */
+  ERR_LOG_DIR_NOT_FOUND = 57,
+  /** SASL Authentication failed */
+  ERR_SASL_AUTHENTICATION_FAILED = 58,
+  /** Unknown Producer Id */
+  ERR_UNKNOWN_PRODUCER_ID = 59,
+  /** Partition reassignment is in progress */
+  ERR_REASSIGNMENT_IN_PROGRESS = 60,
+  /** Delegation Token feature is not enabled */
+  ERR_DELEGATION_TOKEN_AUTH_DISABLED = 61,
+  /** Delegation Token is not found on server */
+  ERR_DELEGATION_TOKEN_NOT_FOUND = 62,
+  /** Specified Principal is not valid Owner/Renewer */
+  ERR_DELEGATION_TOKEN_OWNER_MISMATCH = 63,
+  /** Delegation Token requests are not allowed on this connection */
+  ERR_DELEGATION_TOKEN_REQUEST_NOT_ALLOWED = 64,
+  /** Delegation Token authorization failed */
+  ERR_DELEGATION_TOKEN_AUTHORIZATION_FAILED = 65,
+  /** Delegation Token is expired */
+  ERR_DELEGATION_TOKEN_EXPIRED = 66,
+  /** Supplied principalType is not supported */
+  ERR_INVALID_PRINCIPAL_TYPE = 67,
+  /** The group is not empty */
+  ERR_NON_EMPTY_GROUP = 68,
+  /** The group id does not exist */
+  ERR_GROUP_ID_NOT_FOUND = 69,
+  /** The fetch session ID was not found */
+  ERR_FETCH_SESSION_ID_NOT_FOUND = 70,
+  /** The fetch session epoch is invalid */
+  ERR_INVALID_FETCH_SESSION_EPOCH = 71,
+  /** No matching listener */
+  ERR_LISTENER_NOT_FOUND = 72,
+  /** Topic deletion is disabled */
+  ERR_TOPIC_DELETION_DISABLED = 73,
+  /** Leader epoch is older than broker epoch */
+  ERR_FENCED_LEADER_EPOCH = 74,
+  /** Leader epoch is newer than broker epoch */
+  ERR_UNKNOWN_LEADER_EPOCH = 75,
+  /** Unsupported compression type */
+  ERR_UNSUPPORTED_COMPRESSION_TYPE = 76,
+  /** Broker epoch has changed */
+  ERR_STALE_BROKER_EPOCH = 77,
+  /** Leader high watermark is not caught up */
+  ERR_OFFSET_NOT_AVAILABLE = 78,
+  /** Group member needs a valid member ID */
+  ERR_MEMBER_ID_REQUIRED = 79,
+  /** Preferred leader was not available */
+  ERR_PREFERRED_LEADER_NOT_AVAILABLE = 80,
+  /** Consumer group has reached maximum size */
+  ERR_GROUP_MAX_SIZE_REACHED = 81,
+  /** Static consumer fenced by other consumer with same
+   * group.instance.id. */
+  ERR_FENCED_INSTANCE_ID = 82,
+  /** Eligible partition leaders are not available */
+  ERR_ELIGIBLE_LEADERS_NOT_AVAILABLE = 83,
+  /** Leader election not needed for topic partition */
+  ERR_ELECTION_NOT_NEEDED = 84,
+  /** No partition reassignment is in progress */
+  ERR_NO_REASSIGNMENT_IN_PROGRESS = 85,
+  /** Deleting offsets of a topic while the consumer group is
+   *  subscribed to it */
+  ERR_GROUP_SUBSCRIBED_TO_TOPIC = 86,
+  /** Broker failed to validate record */
+  ERR_INVALID_RECORD = 87,
+  /** There are unstable offsets that need to be cleared */
+  ERR_UNSTABLE_OFFSET_COMMIT = 88,
+  /** Throttling quota has been exceeded */
+  ERR_THROTTLING_QUOTA_EXCEEDED = 89,
+  /** There is a newer producer with the same transactionalId
+   *  which fences the current one */
+  ERR_PRODUCER_FENCED = 90,
+  /** Request illegally referred to resource that does not exist */
+  ERR_RESOURCE_NOT_FOUND = 91,
+  /** Request illegally referred to the same resource twice */
+  ERR_DUPLICATE_RESOURCE = 92,
+  /** Requested credential would not meet criteria for acceptability */
+  ERR_UNACCEPTABLE_CREDENTIAL = 93,
+  /** Indicates that the either the sender or recipient of a
+   *  voter-only request is not one of the expected voters */
+  ERR_INCONSISTENT_VOTER_SET = 94,
+  /** Invalid update version */
+  ERR_INVALID_UPDATE_VERSION = 95,
+  /** Unable to update finalized features due to server error */
+  ERR_FEATURE_UPDATE_FAILED = 96,
+  /** Request principal deserialization failed during forwarding */
+  ERR_PRINCIPAL_DESERIALIZATION_FAILURE = 97
+};
+
+
+/**
+ * @brief Returns a human readable representation of a kafka error.
+ */
+RD_EXPORT
+std::string err2str(RdKafka::ErrorCode err);
+
+
+
+/**
+ * @enum CertificateType
+ * @brief SSL certificate types
+ */
+enum CertificateType {
+  CERT_PUBLIC_KEY,  /**< Client's public key */
+  CERT_PRIVATE_KEY, /**< Client's private key */
+  CERT_CA,          /**< CA certificate */
+  CERT__CNT
+};
+
+/**
+ * @enum CertificateEncoding
+ * @brief SSL certificate encoding
+ */
+enum CertificateEncoding {
+  CERT_ENC_PKCS12, /**< PKCS#12 */
+  CERT_ENC_DER,    /**< DER / binary X.509 ASN1 */
+  CERT_ENC_PEM,    /**< PEM */
+  CERT_ENC__CNT
+};
+
+/**@} */
+
+
+
+/**@cond NO_DOC*/
+/* Forward declarations */
+class Handle;
+class Producer;
+class Message;
+class Headers;
+class Queue;
+class Event;
+class Topic;
+class TopicPartition;
+class Metadata;
+class KafkaConsumer;
+/**@endcond*/
+
+
+/**
+ * @name Error class
+ * @{
+ *
+ */
+
+/**
+ * @brief The Error class is used as a return value from APIs to propagate
+ *        an error. The error consists of an error code which is to be used
+ *        programatically, an error string for showing to the user,
+ *        and various error flags that can be used programmatically to decide
+ *        how to handle the error; e.g., should the operation be retried,
+ *        was it a fatal error, etc.
+ *
+ * Error objects must be deleted explicitly to free its resources.
+ */
+class RD_EXPORT Error {
+ public:
+  /**
+   * @brief Create error object.
+   */
+  static Error *create(ErrorCode code, const std::string *errstr);
+
+  virtual ~Error() {
+  }
+
+  /*
+   * Error accessor methods
+   */
+
+  /**
+   * @returns the error code, e.g., RdKafka::ERR_UNKNOWN_MEMBER_ID.
+   */
+  virtual ErrorCode code() const = 0;
+
+  /**
+   * @returns the error code name, e.g, "ERR_UNKNOWN_MEMBER_ID".
+   */
+  virtual std::string name() const = 0;
+
+  /**
+   * @returns a human readable error string.
+   */
+  virtual std::string str() const = 0;
+
+  /**
+   * @returns true if the error is a fatal error, indicating that the client
+   *          instance is no longer usable, else false.
+   */
+  virtual bool is_fatal() const = 0;
+
+  /**
+   * @returns true if the operation may be retried, else false.
+   */
+  virtual bool is_retriable() const = 0;
+
+  /**
+   * @returns true if the error is an abortable transaction error in which case
+   *          the application must call RdKafka::Producer::abort_transaction()
+   *          and start a new transaction with
+   *          RdKafka::Producer::begin_transaction() if it wishes to proceed
+   *          with transactions.
+   *          Else returns false.
+   *
+   * @remark The return value of this method is only valid for errors returned
+   *         by the transactional API.
+   */
+  virtual bool txn_requires_abort() const = 0;
+};
+
+/**@}*/
+
+
+/**
+ * @name Callback classes
+ * @{
+ *
+ *
+ * librdkafka uses (optional) callbacks to propagate information and
+ * delegate decisions to the application logic.
+ *
+ * An application must call RdKafka::poll() at regular intervals to
+ * serve queued callbacks.
+ */
+
+
+/**
+ * @brief Delivery Report callback class
+ *
+ * The delivery report callback will be called once for each message
+ * accepted by RdKafka::Producer::produce() (et.al) with
+ * RdKafka::Message::err() set to indicate the result of the produce request.
+ *
+ * The callback is called when a message is succesfully produced or
+ * if librdkafka encountered a permanent failure, or the retry counter for
+ * temporary errors has been exhausted.
+ *
+ * An application must call RdKafka::poll() at regular intervals to
+ * serve queued delivery report callbacks.
+
+ */
+class RD_EXPORT DeliveryReportCb {
+ public:
+  /**
+   * @brief Delivery report callback.
+   */
+  virtual void dr_cb(Message &message) = 0;
+
+  virtual ~DeliveryReportCb() {
+  }
+};
+
+
+/**
+ * @brief SASL/OAUTHBEARER token refresh callback class
+ *
+ * The SASL/OAUTHBEARER token refresh callback is triggered via RdKafka::poll()
+ * whenever OAUTHBEARER is the SASL mechanism and a token needs to be retrieved,
+ * typically based on the configuration defined in \c sasl.oauthbearer.config.
+ *
+ * The \c oauthbearer_config argument is the value of the
+ * \c sasl.oauthbearer.config configuration property.
+ *
+ * The callback should invoke RdKafka::Handle::oauthbearer_set_token() or
+ * RdKafka::Handle::oauthbearer_set_token_failure() to indicate success or
+ * failure, respectively.
+ *
+ * The refresh operation is eventable and may be received when an event
+ * callback handler is set with an event type of
+ * \c RdKafka::Event::EVENT_OAUTHBEARER_TOKEN_REFRESH.
+ *
+ * Note that before any SASL/OAUTHBEARER broker connection can succeed the
+ * application must call RdKafka::Handle::oauthbearer_set_token() once -- either
+ * directly or, more typically, by invoking RdKafka::poll() -- in order to
+ * cause retrieval of an initial token to occur.
+ *
+ * An application must call RdKafka::poll() at regular intervals to
+ * serve queued SASL/OAUTHBEARER token refresh callbacks (when
+ * OAUTHBEARER is the SASL mechanism).
+ */
+class RD_EXPORT OAuthBearerTokenRefreshCb {
+ public:
+  /**
+   * @brief SASL/OAUTHBEARER token refresh callback class.
+   *
+   * @param handle The RdKafka::Handle which requires a refreshed token.
+   * @param oauthbearer_config The value of the
+   * \p sasl.oauthbearer.config configuration property for \p handle.
+   */
+  virtual void oauthbearer_token_refresh_cb(
+      RdKafka::Handle *handle,
+      const std::string &oauthbearer_config) = 0;
+
+  virtual ~OAuthBearerTokenRefreshCb() {
+  }
+};
+
+
+/**
+ * @brief Partitioner callback class
+ *
+ * Generic partitioner callback class for implementing custom partitioners.
+ *
+ * @sa RdKafka::Conf::set() \c "partitioner_cb"
+ */
+class RD_EXPORT PartitionerCb {
+ public:
+  /**
+   * @brief Partitioner callback
+   *
+   * Return the partition to use for \p key in \p topic.
+   *
+   * The \p msg_opaque is the same \p msg_opaque provided in the
+   * RdKafka::Producer::produce() call.
+   *
+   * @remark \p key may be NULL or the empty.
+   *
+   * @returns Must return a value between 0 and \p partition_cnt
+   * (non-inclusive). May return RD_KAFKA_PARTITION_UA (-1) if partitioning
+   * failed.
+   *
+   * @sa The callback may use RdKafka::Topic::partition_available() to check
+   *     if a partition has an active leader broker.
+   */
+  virtual int32_t partitioner_cb(const Topic *topic,
+                                 const std::string *key,
+                                 int32_t partition_cnt,
+                                 void *msg_opaque) = 0;
+
+  virtual ~PartitionerCb() {
+  }
+};
+
+/**
+ * @brief  Variant partitioner with key pointer
+ *
+ */
+class PartitionerKeyPointerCb {
+ public:
+  /**
+   * @brief Variant partitioner callback that gets \p key as pointer and length
+   *        instead of as a const std::string *.
+   *
+   * @remark \p key may be NULL or have \p key_len 0.
+   *
+   * @sa See RdKafka::PartitionerCb::partitioner_cb() for exact semantics
+   */
+  virtual int32_t partitioner_cb(const Topic *topic,
+                                 const void *key,
+                                 size_t key_len,
+                                 int32_t partition_cnt,
+                                 void *msg_opaque) = 0;
+
+  virtual ~PartitionerKeyPointerCb() {
+  }
+};
+
+
+
+/**
+ * @brief Event callback class
+ *
+ * Events are a generic interface for propagating errors, statistics, logs, etc
+ * from librdkafka to the application.
+ *
+ * @sa RdKafka::Event
+ */
+class RD_EXPORT EventCb {
+ public:
+  /**
+   * @brief Event callback
+   *
+   * @sa RdKafka::Event
+   */
+  virtual void event_cb(Event &event) = 0;
+
+  virtual ~EventCb() {
+  }
+};
+
+
+/**
+ * @brief Event object class as passed to the EventCb callback.
+ */
+class RD_EXPORT Event {
+ public:
+  /** @brief Event type */
+  enum Type {
+    EVENT_ERROR,   /**< Event is an error condition */
+    EVENT_STATS,   /**< Event is a statistics JSON document */
+    EVENT_LOG,     /**< Event is a log message */
+    EVENT_THROTTLE /**< Event is a throttle level signaling from the broker */
+  };
+
+  /** @brief EVENT_LOG severities (conforms to syslog(3) severities) */
+  enum Severity {
+    EVENT_SEVERITY_EMERG    = 0,
+    EVENT_SEVERITY_ALERT    = 1,
+    EVENT_SEVERITY_CRITICAL = 2,
+    EVENT_SEVERITY_ERROR    = 3,
+    EVENT_SEVERITY_WARNING  = 4,
+    EVENT_SEVERITY_NOTICE   = 5,
+    EVENT_SEVERITY_INFO     = 6,
+    EVENT_SEVERITY_DEBUG    = 7
+  };
+
+  virtual ~Event() {
+  }
+
+  /*
+   * Event Accessor methods
+   */
+
+  /**
+   * @returns The event type
+   * @remark Applies to all event types
+   */
+  virtual Type type() const = 0;
+
+  /**
+   * @returns Event error, if any.
+   * @remark Applies to all event types except THROTTLE
+   */
+  virtual ErrorCode err() const = 0;
+
+  /**
+   * @returns Log severity level.
+   * @remark Applies to LOG event type.
+   */
+  virtual Severity severity() const = 0;
+
+  /**
+   * @returns Log facility string.
+   * @remark Applies to LOG event type.
+   */
+  virtual std::string fac() const = 0;
+
+  /**
+   * @returns Log message string.
+   *
+   * \c EVENT_LOG: Log message string.
+   * \c EVENT_STATS: JSON object (as string).
+   *
+   * @remark Applies to LOG event type.
+   */
+  virtual std::string str() const = 0;
+
+  /**
+   * @returns Throttle time in milliseconds.
+   * @remark Applies to THROTTLE event type.
+   */
+  virtual int throttle_time() const = 0;
+
+  /**
+   * @returns Throttling broker's name.
+   * @remark Applies to THROTTLE event type.
+   */
+  virtual std::string broker_name() const = 0;
+
+  /**
+   * @returns Throttling broker's id.
+   * @remark Applies to THROTTLE event type.
+   */
+  virtual int broker_id() const = 0;
+
+
+  /**
+   * @returns true if this is a fatal error.
+   * @remark Applies to ERROR event type.
+   * @sa RdKafka::Handle::fatal_error()
+   */
+  virtual bool fatal() const = 0;
+};
+
+
+
+/**
+ * @brief Consume callback class
+ */
+class RD_EXPORT ConsumeCb {
+ public:
+  /**
+   * @brief The consume callback is used with
+   *        RdKafka::Consumer::consume_callback()
+   *        methods and will be called for each consumed \p message.
+   *
+   * The callback interface is optional but provides increased performance.
+   */
+  virtual void consume_cb(Message &message, void *opaque) = 0;
+
+  virtual ~ConsumeCb() {
+  }
+};
+
+
+/**
+ * @brief \b KafkaConsumer: Rebalance callback class
+ */
+class RD_EXPORT RebalanceCb {
+ public:
+  /**
+   * @brief Group rebalance callback for use with RdKafka::KafkaConsumer
+   *
+   * Registering a \p rebalance_cb turns off librdkafka's automatic
+   * partition assignment/revocation and instead delegates that responsibility
+   * to the application's \p rebalance_cb.
+   *
+   * The rebalance callback is responsible for updating librdkafka's
+   * assignment set based on the two events: RdKafka::ERR__ASSIGN_PARTITIONS
+   * and RdKafka::ERR__REVOKE_PARTITIONS but should also be able to handle
+   * arbitrary rebalancing failures where \p err is neither of those.
+   * @remark In this latter case (arbitrary error), the application must
+   *         call unassign() to synchronize state.
+   *
+   * For eager/non-cooperative `partition.assignment.strategy` assignors,
+   * such as `range` and `roundrobin`, the application must use
+   * assign assign() to set and unassign() to clear the entire assignment.
+   * For the cooperative assignors, such as `cooperative-sticky`, the
+   * application must use incremental_assign() for ERR__ASSIGN_PARTITIONS and
+   * incremental_unassign() for ERR__REVOKE_PARTITIONS.
+   *
+   * Without a rebalance callback this is done automatically by librdkafka
+   * but registering a rebalance callback gives the application flexibility
+   * in performing other operations along with the assinging/revocation,
+   * such as fetching offsets from an alternate location (on assign)
+   * or manually committing offsets (on revoke).
+   *
+   * @sa RdKafka::KafkaConsumer::assign()
+   * @sa RdKafka::KafkaConsumer::incremental_assign()
+   * @sa RdKafka::KafkaConsumer::incremental_unassign()
+   * @sa RdKafka::KafkaConsumer::assignment_lost()
+   * @sa RdKafka::KafkaConsumer::rebalance_protocol()
+   *
+   * The following example show's the application's responsibilities:
+   * @code
+   *    class MyRebalanceCb : public RdKafka::RebalanceCb {
+   *     public:
+   *      void rebalance_cb (RdKafka::KafkaConsumer *consumer,
+   *                    RdKafka::ErrorCode err,
+   *                    std::vector<RdKafka::TopicPartition*> &partitions) {
+   *         if (err == RdKafka::ERR__ASSIGN_PARTITIONS) {
+   *           // application may load offets from arbitrary external
+   *           // storage here and update \p partitions
+   *           if (consumer->rebalance_protocol() == "COOPERATIVE")
+   *             consumer->incremental_assign(partitions);
+   *           else
+   *             consumer->assign(partitions);
+   *
+   *         } else if (err == RdKafka::ERR__REVOKE_PARTITIONS) {
+   *           // Application may commit offsets manually here
+   *           // if auto.commit.enable=false
+   *           if (consumer->rebalance_protocol() == "COOPERATIVE")
+   *             consumer->incremental_unassign(partitions);
+   *           else
+   *             consumer->unassign();
+   *
+   *         } else {
+   *           std::cerr << "Rebalancing error: " <<
+   *                        RdKafka::err2str(err) << std::endl;
+   *           consumer->unassign();
+   *         }
+   *     }
+   *  }
+   * @endcode
+   *
+   * @remark The above example lacks error handling for assign calls, see
+   *         the examples/ directory.
+   */
+  virtual void rebalance_cb(RdKafka::KafkaConsumer *consumer,
+                            RdKafka::ErrorCode err,
+                            std::vector<TopicPartition *> &partitions) = 0;
+
+  virtual ~RebalanceCb() {
+  }
+};
+
+
+/**
+ * @brief Offset Commit callback class
+ */
+class RD_EXPORT OffsetCommitCb {
+ public:
+  /**
+   * @brief Set offset commit callback for use with consumer groups
+   *
+   * The results of automatic or manual offset commits will be scheduled
+   * for this callback and is served by RdKafka::KafkaConsumer::consume().
+   *
+   * If no partitions had valid offsets to commit this callback will be called
+   * with \p err == ERR__NO_OFFSET which is not to be considered an error.
+   *
+   * The \p offsets list contains per-partition information:
+   *   - \c topic      The topic committed
+   *   - \c partition  The partition committed
+   *   - \c offset:    Committed offset (attempted)
+   *   - \c err:       Commit error
+   */
+  virtual void offset_commit_cb(RdKafka::ErrorCode err,
+                                std::vector<TopicPartition *> &offsets) = 0;
+
+  virtual ~OffsetCommitCb() {
+  }
+};
+
+
+
+/**
+ * @brief SSL broker certificate verification class.
+ *
+ * @remark Class instance must outlive the RdKafka client instance.
+ */
+class RD_EXPORT SslCertificateVerifyCb {
+ public:
+  /**
+   * @brief SSL broker certificate verification callback.
+   *
+   * The verification callback is triggered from internal librdkafka threads
+   * upon connecting to a broker. On each connection attempt the callback
+   * will be called for each certificate in the broker's certificate chain,
+   * starting at the root certification, as long as the application callback
+   * returns 1 (valid certificate).
+   *
+   * \p broker_name and \p broker_id correspond to the broker the connection
+   * is being made to.
+   * The \c x509_error argument indicates if OpenSSL's verification of
+   * the certificate succeed (0) or failed (an OpenSSL error code).
+   * The application may set the SSL context error code by returning 0
+   * from the verify callback and providing a non-zero SSL context error code
+   * in \p x509_error.
+   * If the verify callback sets \p x509_error to 0, returns 1, and the
+   * original \p x509_error was non-zero, the error on the SSL context will
+   * be cleared.
+   * \p x509_error is always a valid pointer to an int.
+   *
+   * \p depth is the depth of the current certificate in the chain, starting
+   * at the root certificate.
+   *
+   * The certificate itself is passed in binary DER format in \p buf of
+   * size \p size.
+   *
+   * The callback must 1 if verification succeeds, or 0 if verification fails
+   * and write a human-readable error message
+   * to \p errstr.
+   *
+   * @warning This callback will be called from internal librdkafka threads.
+   *
+   * @remark See <openssl/x509_vfy.h> in the OpenSSL source distribution
+   *         for a list of \p x509_error codes.
+   */
+  virtual bool ssl_cert_verify_cb(const std::string &broker_name,
+                                  int32_t broker_id,
+                                  int *x509_error,
+                                  int depth,
+                                  const char *buf,
+                                  size_t size,
+                                  std::string &errstr) = 0;
+
+  virtual ~SslCertificateVerifyCb() {
+  }
+};
+
+
+/**
+ * @brief \b Portability: SocketCb callback class
+ *
+ */
+class RD_EXPORT SocketCb {
+ public:
+  /**
+   * @brief Socket callback
+   *
+   * The socket callback is responsible for opening a socket
+   * according to the supplied \p domain, \p type and \p protocol.
+   * The socket shall be created with \c CLOEXEC set in a racefree fashion, if
+   * possible.
+   *
+   * It is typically not required to register an alternative socket
+   * implementation
+   *
+   * @returns The socket file descriptor or -1 on error (\c errno must be set)
+   */
+  virtual int socket_cb(int domain, int type, int protocol) = 0;
+
+  virtual ~SocketCb() {
+  }
+};
+
+
+/**
+ * @brief \b Portability: OpenCb callback class
+ *
+ */
+class RD_EXPORT OpenCb {
+ public:
+  /**
+   * @brief Open callback
+   * The open callback is responsible for opening the file specified by
+   * \p pathname, using \p flags and \p mode.
+   * The file shall be opened with \c CLOEXEC set in a racefree fashion, if
+   * possible.
+   *
+   * It is typically not required to register an alternative open implementation
+   *
+   * @remark Not currently available on native Win32
+   */
+  virtual int open_cb(const std::string &path, int flags, int mode) = 0;
+
+  virtual ~OpenCb() {
+  }
+};
+
+
+/**@}*/
+
+
+
+/**
+ * @name Configuration interface
+ * @{
+ *
+ */
+
+/**
+ * @brief Configuration interface
+ *
+ * Holds either global or topic configuration that are passed to
+ * RdKafka::Consumer::create(), RdKafka::Producer::create(),
+ * RdKafka::KafkaConsumer::create(), etc.
+ *
+ * @sa CONFIGURATION.md for the full list of supported properties.
+ */
+class RD_EXPORT Conf {
+ public:
+  /**
+   * @brief Configuration object type
+   */
+  enum ConfType {
+    CONF_GLOBAL, /**< Global configuration */
+    CONF_TOPIC   /**< Topic specific configuration */
+  };
+
+  /**
+   * @brief RdKafka::Conf::Set() result code
+   */
+  enum ConfResult {
+    CONF_UNKNOWN = -2, /**< Unknown configuration property */
+    CONF_INVALID = -1, /**< Invalid configuration value */
+    CONF_OK      = 0   /**< Configuration property was succesfully set */
+  };
+
+
+  /**
+   * @brief Create configuration object
+   */
+  static Conf *create(ConfType type);
+
+  virtual ~Conf() {
+  }
+
+  /**
+   * @brief Set configuration property \p name to value \p value.
+   *
+   * Fallthrough:
+   * Topic-level configuration properties may be set using this interface
+   * in which case they are applied on the \c default_topic_conf.
+   * If no \c default_topic_conf has been set one will be created.
+   * Any sub-sequent set("default_topic_conf", ..) calls will
+   * replace the current default topic configuration.
+
+   * @returns CONF_OK on success, else writes a human readable error
+   *          description to \p errstr on error.
+   */
+  virtual Conf::ConfResult set(const std::string &name,
+                               const std::string &value,
+                               std::string &errstr) = 0;
+
+  /** @brief Use with \p name = \c \"dr_cb\" */
+  virtual Conf::ConfResult set(const std::string &name,
+                               DeliveryReportCb *dr_cb,
+                               std::string &errstr) = 0;
+
+  /** @brief Use with \p name = \c \"oauthbearer_token_refresh_cb\" */
+  virtual Conf::ConfResult set(
+      const std::string &name,
+      OAuthBearerTokenRefreshCb *oauthbearer_token_refresh_cb,
+      std::string &errstr) = 0;
+
+  /** @brief Use with \p name = \c \"event_cb\" */
+  virtual Conf::ConfResult set(const std::string &name,
+                               EventCb *event_cb,
+                               std::string &errstr) = 0;
+
+  /** @brief Use with \p name = \c \"default_topic_conf\"
+   *
+   * Sets the default topic configuration to use for for automatically
+   * subscribed topics.
+   *
+   * @sa RdKafka::KafkaConsumer::subscribe()
+   */
+  virtual Conf::ConfResult set(const std::string &name,
+                               const Conf *topic_conf,
+                               std::string &errstr) = 0;
+
+  /** @brief Use with \p name = \c \"partitioner_cb\" */
+  virtual Conf::ConfResult set(const std::string &name,
+                               PartitionerCb *partitioner_cb,
+                               std::string &errstr) = 0;
+
+  /** @brief Use with \p name = \c \"partitioner_key_pointer_cb\" */
+  virtual Conf::ConfResult set(const std::string &name,
+                               PartitionerKeyPointerCb *partitioner_kp_cb,
+                               std::string &errstr) = 0;
+
+  /** @brief Use with \p name = \c \"socket_cb\" */
+  virtual Conf::ConfResult set(const std::string &name,
+                               SocketCb *socket_cb,
+                               std::string &errstr) = 0;
+
+  /** @brief Use with \p name = \c \"open_cb\" */
+  virtual Conf::ConfResult set(const std::string &name,
+                               OpenCb *open_cb,
+                               std::string &errstr) = 0;
+
+  /** @brief Use with \p name = \c \"rebalance_cb\" */
+  virtual Conf::ConfResult set(const std::string &name,
+                               RebalanceCb *rebalance_cb,
+                               std::string &errstr) = 0;
+
+  /** @brief Use with \p name = \c \"offset_commit_cb\" */
+  virtual Conf::ConfResult set(const std::string &name,
+                               OffsetCommitCb *offset_commit_cb,
+                               std::string &errstr) = 0;
+
+  /** @brief Use with \p name = \c \"ssl_cert_verify_cb\".
+   *  @returns CONF_OK on success or CONF_INVALID if SSL is
+   *           not supported in this build.
+   */
+  virtual Conf::ConfResult set(const std::string &name,
+                               SslCertificateVerifyCb *ssl_cert_verify_cb,
+                               std::string &errstr) = 0;
+
+  /**
+   * @brief Set certificate/key \p cert_type from the \p cert_enc encoded
+   *        memory at \p buffer of \p size bytes.
+   *
+   * @param cert_type Certificate or key type to configure.
+   * @param cert_enc  Buffer \p encoding type.
+   * @param buffer Memory pointer to encoded certificate or key.
+   *               The memory is not referenced after this function returns.
+   * @param size Size of memory at \p buffer.
+   * @param errstr A human-readable error string will be written to this string
+   *               on failure.
+   *
+   * @returns CONF_OK on success or CONF_INVALID if the memory in
+   *          \p buffer is of incorrect encoding, or if librdkafka
+   *          was not built with SSL support.
+   *
+   * @remark Calling this method multiple times with the same \p cert_type
+   *         will replace the previous value.
+   *
+   * @remark Calling this method with \p buffer set to NULL will clear the
+   *         configuration for \p cert_type.
+   *
+   * @remark The private key may require a password, which must be specified
+   *         with the `ssl.key.password` configuration property prior to
+   *         calling this function.
+   *
+   * @remark Private and public keys in PEM format may also be set with the
+   *         `ssl.key.pem` and `ssl.certificate.pem` configuration properties.
+   *
+   * @remark CA certificate in PEM format may also be set with the
+   *         `ssl.ca.pem` configuration property.
+   *
+   * @remark When librdkafka is linked to OpenSSL 3.0 and the certificate is
+   *         encoded using an obsolete cipher, it might be necessary to set up
+   *         an OpenSSL configuration file to load the "legacy" provider and
+   *         set the OPENSSL_CONF environment variable.
+   *         See
+   * https://github.com/openssl/openssl/blob/master/README-PROVIDERS.md for more
+   * information.
+   */
+  virtual Conf::ConfResult set_ssl_cert(RdKafka::CertificateType cert_type,
+                                        RdKafka::CertificateEncoding cert_enc,
+                                        const void *buffer,
+                                        size_t size,
+                                        std::string &errstr) = 0;
+
+  /** @brief Query single configuration value
+   *
+   * Do not use this method to get callbacks registered by the configuration
+   * file. Instead use the specific get() methods with the specific callback
+   * parameter in the signature.
+   *
+   * Fallthrough:
+   * Topic-level configuration properties from the \c default_topic_conf
+   * may be retrieved using this interface.
+   *
+   *  @returns CONF_OK if the property was set previously set and
+   *           returns the value in \p value. */
+  virtual Conf::ConfResult get(const std::string &name,
+                               std::string &value) const = 0;
+
+  /** @brief Query single configuration value
+   *  @returns CONF_OK if the property was set previously set and
+   *           returns the value in \p dr_cb. */
+  virtual Conf::ConfResult get(DeliveryReportCb *&dr_cb) const = 0;
+
+  /** @brief Query single configuration value
+   *  @returns CONF_OK if the property was set previously set and
+   *           returns the value in \p oauthbearer_token_refresh_cb. */
+  virtual Conf::ConfResult get(
+      OAuthBearerTokenRefreshCb *&oauthbearer_token_refresh_cb) const = 0;
+
+  /** @brief Query single configuration value
+   *  @returns CONF_OK if the property was set previously set and
+   *           returns the value in \p event_cb. */
+  virtual Conf::ConfResult get(EventCb *&event_cb) const = 0;
+
+  /** @brief Query single configuration value
+   *  @returns CONF_OK if the property was set previously set and
+   *           returns the value in \p partitioner_cb. */
+  virtual Conf::ConfResult get(PartitionerCb *&partitioner_cb) const = 0;
+
+  /** @brief Query single configuration value
+   *  @returns CONF_OK if the property was set previously set and
+   *           returns the value in \p partitioner_kp_cb. */
+  virtual Conf::ConfResult get(
+      PartitionerKeyPointerCb *&partitioner_kp_cb) const = 0;
+
+  /** @brief Query single configuration value
+   *  @returns CONF_OK if the property was set previously set and
+   *           returns the value in \p socket_cb. */
+  virtual Conf::ConfResult get(SocketCb *&socket_cb) const = 0;
+
+  /** @brief Query single configuration value
+   *  @returns CONF_OK if the property was set previously set and
+   *           returns the value in \p open_cb. */
+  virtual Conf::ConfResult get(OpenCb *&open_cb) const = 0;
+
+  /** @brief Query single configuration value
+   *  @returns CONF_OK if the property was set previously set and
+   *           returns the value in \p rebalance_cb. */
+  virtual Conf::ConfResult get(RebalanceCb *&rebalance_cb) const = 0;
+
+  /** @brief Query single configuration value
+   *  @returns CONF_OK if the property was set previously set and
+   *           returns the value in \p offset_commit_cb. */
+  virtual Conf::ConfResult get(OffsetCommitCb *&offset_commit_cb) const = 0;
+
+  /** @brief Use with \p name = \c \"ssl_cert_verify_cb\" */
+  virtual Conf::ConfResult get(
+      SslCertificateVerifyCb *&ssl_cert_verify_cb) const = 0;
+
+  /** @brief Dump configuration names and values to list containing
+   *         name,value tuples */
+  virtual std::list<std::string> *dump() = 0;
+
+  /** @brief Use with \p name = \c \"consume_cb\" */
+  virtual Conf::ConfResult set(const std::string &name,
+                               ConsumeCb *consume_cb,
+                               std::string &errstr) = 0;
+
+  /**
+   * @brief Returns the underlying librdkafka C rd_kafka_conf_t handle.
+   *
+   * @warning Calling the C API on this handle is not recommended and there
+   *          is no official support for it, but for cases where the C++
+   *          does not provide the proper functionality this C handle can be
+   *          used to interact directly with the core librdkafka API.
+   *
+   * @remark The lifetime of the returned pointer is the same as the Conf
+   *         object this method is called on.
+   *
+   * @remark Include <rdkafka/rdkafka.h> prior to including
+   *         <rdkafka/rdkafkacpp.h>
+   *
+   * @returns \c rd_kafka_conf_t* if this is a CONF_GLOBAL object, else NULL.
+   */
+  virtual struct rd_kafka_conf_s *c_ptr_global() = 0;
+
+  /**
+   * @brief Returns the underlying librdkafka C rd_kafka_topic_conf_t handle.
+   *
+   * @warning Calling the C API on this handle is not recommended and there
+   *          is no official support for it, but for cases where the C++
+   *          does not provide the proper functionality this C handle can be
+   *          used to interact directly with the core librdkafka API.
+   *
+   * @remark The lifetime of the returned pointer is the same as the Conf
+   *         object this method is called on.
+   *
+   * @remark Include <rdkafka/rdkafka.h> prior to including
+   *         <rdkafka/rdkafkacpp.h>
+   *
+   * @returns \c rd_kafka_topic_conf_t* if this is a CONF_TOPIC object,
+   *          else NULL.
+   */
+  virtual struct rd_kafka_topic_conf_s *c_ptr_topic() = 0;
+
+  /**
+   * @brief Set callback_data for ssl engine.
+   *
+   * @remark The \c ssl.engine.location configuration must be set for this
+   *         to have affect.
+   *
+   * @remark The memory pointed to by \p value must remain valid for the
+   *         lifetime of the configuration object and any Kafka clients that
+   *         use it.
+   *
+   * @returns CONF_OK on success, else CONF_INVALID.
+   */
+  virtual Conf::ConfResult set_engine_callback_data(void *value,
+                                                    std::string &errstr) = 0;
+
+
+  /** @brief Enable/disable creation of a queue specific to SASL events
+   *        and callbacks.
+   *
+   * For SASL mechanisms that trigger callbacks (currently OAUTHBEARER) this
+   * configuration API allows an application to get a dedicated
+   * queue for the SASL events/callbacks. After enabling the queue with this API
+   * the application can retrieve the queue by calling
+   * RdKafka::Handle::get_sasl_queue() on the client instance.
+   * This queue may then be served directly by the application
+   * (RdKafka::Queue::poll()) or forwarded to another queue, such as
+   * the background queue.
+   *
+   * A convenience function is available to automatically forward the SASL queue
+   * to librdkafka's background thread, see
+   * RdKafka::Handle::sasl_background_callbacks_enable().
+   *
+   * By default (\p enable = false) the main queue (as served by
+   * RdKafka::Handle::poll(), et.al.) is used for SASL callbacks.
+   *
+   * @remark The SASL queue is currently only used by the SASL OAUTHBEARER "
+   *         mechanism's token refresh callback.
+   */
+  virtual Conf::ConfResult enable_sasl_queue(bool enable,
+                                             std::string &errstr) = 0;
+};
+
+/**@}*/
+
+
+/**
+ * @name Kafka base client handle
+ * @{
+ *
+ */
+
+/**
+ * @brief Base handle, super class for specific clients.
+ */
+class RD_EXPORT Handle {
+ public:
+  virtual ~Handle() {
+  }
+
+  /** @returns the name of the handle */
+  virtual std::string name() const = 0;
+
+  /**
+   * @brief Returns the client's broker-assigned group member id
+   *
+   * @remark This currently requires the high-level KafkaConsumer
+   *
+   * @returns Last assigned member id, or empty string if not currently
+   *          a group member.
+   */
+  virtual std::string memberid() const = 0;
+
+
+  /**
+   * @brief Polls the provided kafka handle for events.
+   *
+   * Events will trigger application provided callbacks to be called.
+   *
+   * The \p timeout_ms argument specifies the maximum amount of time
+   * (in milliseconds) that the call will block waiting for events.
+   * For non-blocking calls, provide 0 as \p timeout_ms.
+   * To wait indefinately for events, provide -1.
+   *
+   * Events:
+   *   - delivery report callbacks (if an RdKafka::DeliveryCb is configured)
+   * [producer]
+   *   - event callbacks (if an RdKafka::EventCb is configured) [producer &
+   * consumer]
+   *
+   * @remark  An application should make sure to call poll() at regular
+   *          intervals to serve any queued callbacks waiting to be called.
+   *
+   * @warning This method MUST NOT be used with the RdKafka::KafkaConsumer,
+   *          use its RdKafka::KafkaConsumer::consume() instead.
+   *
+   * @returns the number of events served.
+   */
+  virtual int poll(int timeout_ms) = 0;
+
+  /**
+   * @brief  Returns the current out queue length
+   *
+   * The out queue contains messages and requests waiting to be sent to,
+   * or acknowledged by, the broker.
+   */
+  virtual int outq_len() = 0;
+
+  /**
+   * @brief Request Metadata from broker.
+   *
+   * Parameters:
+   *  \p all_topics  - if non-zero: request info about all topics in cluster,
+   *                   if zero: only request info about locally known topics.
+   *  \p only_rkt    - only request info about this topic
+   *  \p metadatap   - pointer to hold metadata result.
+   *                   The \p *metadatap pointer must be released with \c
+   * delete. \p timeout_ms  - maximum response time before failing.
+   *
+   * @returns RdKafka::ERR_NO_ERROR on success (in which case \p *metadatap
+   * will be set), else RdKafka::ERR__TIMED_OUT on timeout or
+   * other error code on error.
+   */
+  virtual ErrorCode metadata(bool all_topics,
+                             const Topic *only_rkt,
+                             Metadata **metadatap,
+                             int timeout_ms) = 0;
+
+
+  /**
+   * @brief Pause producing or consumption for the provided list of partitions.
+   *
+   * Success or error is returned per-partition in the \p partitions list.
+   *
+   * @returns ErrorCode::NO_ERROR
+   *
+   * @sa resume()
+   */
+  virtual ErrorCode pause(std::vector<TopicPartition *> &partitions) = 0;
+
+
+  /**
+   * @brief Resume producing or consumption for the provided list of partitions.
+   *
+   * Success or error is returned per-partition in the \p partitions list.
+   *
+   * @returns ErrorCode::NO_ERROR
+   *
+   * @sa pause()
+   */
+  virtual ErrorCode resume(std::vector<TopicPartition *> &partitions) = 0;
+
+
+  /**
+   * @brief Query broker for low (oldest/beginning)
+   *        and high (newest/end) offsets for partition.
+   *
+   * Offsets are returned in \p *low and \p *high respectively.
+   *
+   * @returns RdKafka::ERR_NO_ERROR on success or an error code on failure.
+   */
+  virtual ErrorCode query_watermark_offsets(const std::string &topic,
+                                            int32_t partition,
+                                            int64_t *low,
+                                            int64_t *high,
+                                            int timeout_ms) = 0;
+
+  /**
+   * @brief Get last known low (oldest/beginning)
+   *        and high (newest/end) offsets for partition.
+   *
+   * The low offset is updated periodically (if statistics.interval.ms is set)
+   * while the high offset is updated on each fetched message set from the
+   * broker.
+   *
+   * If there is no cached offset (either low or high, or both) then
+   * OFFSET_INVALID will be returned for the respective offset.
+   *
+   * Offsets are returned in \p *low and \p *high respectively.
+   *
+   * @returns RdKafka::ERR_NO_ERROR on success or an error code on failure.
+   *
+   * @remark Shall only be used with an active consumer instance.
+   */
+  virtual ErrorCode get_watermark_offsets(const std::string &topic,
+                                          int32_t partition,
+                                          int64_t *low,
+                                          int64_t *high) = 0;
+
+
+  /**
+   * @brief Look up the offsets for the given partitions by timestamp.
+   *
+   * The returned offset for each partition is the earliest offset whose
+   * timestamp is greater than or equal to the given timestamp in the
+   * corresponding partition.
+   *
+   * The timestamps to query are represented as \c offset in \p offsets
+   * on input, and \c offset() will return the closest earlier offset
+   * for the timestamp on output.
+   *
+   * Timestamps are expressed as milliseconds since epoch (UTC).
+   *
+   * The function will block for at most \p timeout_ms milliseconds.
+   *
+   * @remark Duplicate Topic+Partitions are not supported.
+   * @remark Errors are also returned per TopicPartition, see \c err()
+   *
+   * @returns an error code for general errors, else RdKafka::ERR_NO_ERROR
+   *          in which case per-partition errors might be set.
+   */
+  virtual ErrorCode offsetsForTimes(std::vector<TopicPartition *> &offsets,
+                                    int timeout_ms) = 0;
+
+
+  /**
+   * @brief Retrieve queue for a given partition.
+   *
+   * @returns The fetch queue for the given partition if successful. Else,
+   *          NULL is returned.
+   *
+   * @remark This function only works on consumers.
+   */
+  virtual Queue *get_partition_queue(const TopicPartition *partition) = 0;
+
+  /**
+   * @brief Forward librdkafka logs (and debug) to the specified queue
+   *        for serving with one of the ..poll() calls.
+   *
+   *        This allows an application to serve log callbacks (\c log_cb)
+   *        in its thread of choice.
+   *
+   * @param queue Queue to forward logs to. If the value is NULL the logs
+   *        are forwarded to the main queue.
+   *
+   * @remark The configuration property \c log.queue MUST also be set to true.
+   *
+   * @remark librdkafka maintains its own reference to the provided queue.
+   *
+   * @returns ERR_NO_ERROR on success or an error code on error.
+   */
+  virtual ErrorCode set_log_queue(Queue *queue) = 0;
+
+  /**
+   * @brief Cancels the current callback dispatcher (Handle::poll(),
+   *        KafkaConsumer::consume(), etc).
+   *
+   * A callback may use this to force an immediate return to the calling
+   * code (caller of e.g. Handle::poll()) without processing any further
+   * events.
+   *
+   * @remark This function MUST ONLY be called from within a
+   *         librdkafka callback.
+   */
+  virtual void yield() = 0;
+
+  /**
+   * @brief Returns the ClusterId as reported in broker metadata.
+   *
+   * @param timeout_ms If there is no cached value from metadata retrieval
+   *                   then this specifies the maximum amount of time
+   *                   (in milliseconds) the call will block waiting
+   *                   for metadata to be retrieved.
+   *                   Use 0 for non-blocking calls.
+   *
+   * @remark Requires broker version >=0.10.0 and api.version.request=true.
+   *
+   * @returns Last cached ClusterId, or empty string if no ClusterId could be
+   *          retrieved in the allotted timespan.
+   */
+  virtual std::string clusterid(int timeout_ms) = 0;
+
+  /**
+   * @brief Returns the underlying librdkafka C rd_kafka_t handle.
+   *
+   * @warning Calling the C API on this handle is not recommended and there
+   *          is no official support for it, but for cases where the C++
+   *          does not provide the proper functionality this C handle can be
+   *          used to interact directly with the core librdkafka API.
+   *
+   * @remark The lifetime of the returned pointer is the same as the Topic
+   *         object this method is called on.
+   *
+   * @remark Include <rdkafka/rdkafka.h> prior to including
+   *         <rdkafka/rdkafkacpp.h>
+   *
+   * @returns \c rd_kafka_t*
+   */
+  virtual struct rd_kafka_s *c_ptr() = 0;
+
+  /**
+   * @brief Returns the current ControllerId (controller broker id)
+   *        as reported in broker metadata.
+   *
+   * @param timeout_ms If there is no cached value from metadata retrieval
+   *                   then this specifies the maximum amount of time
+   *                   (in milliseconds) the call will block waiting
+   *                   for metadata to be retrieved.
+   *                   Use 0 for non-blocking calls.
+   *
+   * @remark Requires broker version >=0.10.0 and api.version.request=true.
+   *
+   * @returns Last cached ControllerId, or -1 if no ControllerId could be
+   *          retrieved in the allotted timespan.
+   */
+  virtual int32_t controllerid(int timeout_ms) = 0;
+
+
+  /**
+   * @brief Returns the first fatal error set on this client instance,
+   *        or ERR_NO_ERROR if no fatal error has occurred.
+   *
+   * This function is to be used with the Idempotent Producer and
+   * the Event class for \c EVENT_ERROR events to detect fatal errors.
+   *
+   * Generally all errors raised by the error event are to be considered
+   * informational and temporary, the client will try to recover from all
+   * errors in a graceful fashion (by retrying, etc).
+   *
+   * However, some errors should logically be considered fatal to retain
+   * consistency; in particular a set of errors that may occur when using the
+   * Idempotent Producer and the in-order or exactly-once producer guarantees
+   * can't be satisfied.
+   *
+   * @param errstr A human readable error string if a fatal error was set.
+   *
+   * @returns ERR_NO_ERROR if no fatal error has been raised, else
+   *          any other error code.
+   */
+  virtual ErrorCode fatal_error(std::string &errstr) const = 0;
+
+  /**
+   * @brief Set SASL/OAUTHBEARER token and metadata
+   *
+   * @param token_value the mandatory token value to set, often (but not
+   *  necessarily) a JWS compact serialization as per
+   *  https://tools.ietf.org/html/rfc7515#section-3.1.
+   * @param md_lifetime_ms when the token expires, in terms of the number of
+   *  milliseconds since the epoch.
+   * @param md_principal_name the Kafka principal name associated with the
+   *  token.
+   * @param extensions potentially empty SASL extension keys and values where
+   *  element [i] is the key and [i+1] is the key's value, to be communicated
+   *  to the broker as additional key-value pairs during the initial client
+   *  response as per https://tools.ietf.org/html/rfc7628#section-3.1.  The
+   *  number of SASL extension keys plus values must be a non-negative multiple
+   *  of 2. Any provided keys and values are copied.
+   * @param errstr A human readable error string is written here, only if
+   *  there is an error.
+   *
+   * The SASL/OAUTHBEARER token refresh callback should invoke
+   * this method upon success. The extension keys must not include the reserved
+   * key "`auth`", and all extension keys and values must conform to the
+   * required format as per https://tools.ietf.org/html/rfc7628#section-3.1:
+   *
+   *     key            = 1*(ALPHA)
+   *     value          = *(VCHAR / SP / HTAB / CR / LF )
+   *
+   * @returns \c RdKafka::ERR_NO_ERROR on success, otherwise \p errstr set
+   *              and:<br>
+   *          \c RdKafka::ERR__INVALID_ARG if any of the arguments are
+   *              invalid;<br>
+   *          \c RdKafka::ERR__NOT_IMPLEMENTED if SASL/OAUTHBEARER is not
+   *              supported by this build;<br>
+   *          \c RdKafka::ERR__STATE if SASL/OAUTHBEARER is supported but is
+   *              not configured as the client's authentication mechanism.<br>
+   *
+   * @sa RdKafka::oauthbearer_set_token_failure
+   * @sa RdKafka::Conf::set() \c "oauthbearer_token_refresh_cb"
+   */
+  virtual ErrorCode oauthbearer_set_token(
+      const std::string &token_value,
+      int64_t md_lifetime_ms,
+      const std::string &md_principal_name,
+      const std::list<std::string> &extensions,
+      std::string &errstr) = 0;
+
+  /**
+   * @brief SASL/OAUTHBEARER token refresh failure indicator.
+   *
+   * @param errstr human readable error reason for failing to acquire a token.
+   *
+   * The SASL/OAUTHBEARER token refresh callback should
+   * invoke this method upon failure to refresh the token.
+   *
+   * @returns \c RdKafka::ERR_NO_ERROR on success, otherwise:<br>
+   *          \c RdKafka::ERR__NOT_IMPLEMENTED if SASL/OAUTHBEARER is not
+   *              supported by this build;<br>
+   *          \c RdKafka::ERR__STATE if SASL/OAUTHBEARER is supported but is
+   *              not configured as the client's authentication mechanism.
+   *
+   * @sa RdKafka::oauthbearer_set_token
+   * @sa RdKafka::Conf::set() \c "oauthbearer_token_refresh_cb"
+   */
+  virtual ErrorCode oauthbearer_set_token_failure(
+      const std::string &errstr) = 0;
+
+  /**
+   * @brief Enable SASL OAUTHBEARER refresh callbacks on the librdkafka
+   *        background thread.
+   *
+   * This serves as an alternative for applications that do not
+   * call RdKafka::Handle::poll() (et.al.) at regular intervals.
+   */
+  virtual Error *sasl_background_callbacks_enable() = 0;
+
+
+  /**
+   * @returns the SASL callback queue, if enabled, else NULL.
+   *
+   * @sa RdKafka::Conf::enable_sasl_queue()
+   */
+  virtual Queue *get_sasl_queue() = 0;
+
+  /**
+   * @returns the librdkafka background thread queue.
+   */
+  virtual Queue *get_background_queue() = 0;
+
+
+
+  /**
+   * @brief Allocate memory using the same allocator librdkafka uses.
+   *
+   * This is typically an abstraction for the malloc(3) call and makes sure
+   * the application can use the same memory allocator as librdkafka for
+   * allocating pointers that are used by librdkafka.
+   *
+   * @remark Memory allocated by mem_malloc() must be freed using
+   *         mem_free().
+   */
+  virtual void *mem_malloc(size_t size) = 0;
+
+  /**
+   * @brief Free pointer returned by librdkafka
+   *
+   * This is typically an abstraction for the free(3) call and makes sure
+   * the application can use the same memory allocator as librdkafka for
+   * freeing pointers returned by librdkafka.
+   *
+   * In standard setups it is usually not necessary to use this interface
+   * rather than the free(3) function.
+   *
+   * @remark mem_free() must only be used for pointers returned by APIs
+   *         that explicitly mention using this function for freeing.
+   */
+  virtual void mem_free(void *ptr) = 0;
+
+  /**
+   * @brief Sets SASL credentials used for SASL PLAIN and SCRAM mechanisms by
+   *        this Kafka client.
+   *
+   * This function sets or resets the SASL username and password credentials
+   * used by this Kafka client. The new credentials will be used the next time
+   * this client needs to authenticate to a broker.
+   * will not disconnect existing connections that might have been made using
+   * the old credentials.
+   *
+   * @remark This function only applies to the SASL PLAIN and SCRAM mechanisms.
+   *
+   * @returns NULL on success or an error object on error.
+   */
+  virtual Error *sasl_set_credentials(const std::string &username,
+                                      const std::string &password) = 0;
+};
+
+
+/**@}*/
+
+
+/**
+ * @name Topic and partition objects
+ * @{
+ *
+ */
+
+/**
+ * @brief Topic+Partition
+ *
+ * This is a generic type to hold a single partition and various
+ * information about it.
+ *
+ * Is typically used with std::vector<RdKafka::TopicPartition*> to provide
+ * a list of partitions for different operations.
+ */
+class RD_EXPORT TopicPartition {
+ public:
+  /**
+   * @brief Create topic+partition object for \p topic and \p partition.
+   *
+   * Use \c delete to deconstruct.
+   */
+  static TopicPartition *create(const std::string &topic, int partition);
+
+  /**
+   * @brief Create topic+partition object for \p topic and \p partition
+   *        with offset \p offset.
+   *
+   * Use \c delete to deconstruct.
+   */
+  static TopicPartition *create(const std::string &topic,
+                                int partition,
+                                int64_t offset);
+
+  virtual ~TopicPartition() = 0;
+
+  /**
+   * @brief Destroy/delete the TopicPartitions in \p partitions
+   *        and clear the vector.
+   */
+  static void destroy(std::vector<TopicPartition *> &partitions);
+
+  /** @returns topic name */
+  virtual const std::string &topic() const = 0;
+
+  /** @returns partition id */
+  virtual int partition() const = 0;
+
+  /** @returns offset (if applicable) */
+  virtual int64_t offset() const = 0;
+
+  /** @brief Set offset */
+  virtual void set_offset(int64_t offset) = 0;
+
+  /** @returns error code (if applicable) */
+  virtual ErrorCode err() const = 0;
+
+  /** @brief Get partition leader epoch, or -1 if not known or relevant. */
+  virtual int32_t get_leader_epoch() = 0;
+
+  /** @brief Set partition leader epoch. */
+  virtual void set_leader_epoch(int32_t leader_epoch) = 0;
+};
+
+
+
+/**
+ * @brief Topic handle
+ *
+ */
+class RD_EXPORT Topic {
+ public:
+  /**
+   * @brief Unassigned partition.
+   *
+   * The unassigned partition is used by the producer API for messages
+   * that should be partitioned using the configured or default partitioner.
+   */
+  static const int32_t PARTITION_UA;
+
+  /** @brief Special offsets */
+  static const int64_t OFFSET_BEGINNING; /**< Consume from beginning */
+  static const int64_t OFFSET_END;       /**< Consume from end */
+  static const int64_t OFFSET_STORED;    /**< Use offset storage */
+  static const int64_t OFFSET_INVALID;   /**< Invalid offset */
+
+
+  /**
+   * @brief Creates a new topic handle for topic named \p topic_str
+   *
+   * \p conf is an optional configuration for the topic  that will be used
+   * instead of the default topic configuration.
+   * The \p conf object is reusable after this call.
+   *
+   * @returns the new topic handle or NULL on error (see \p errstr).
+   */
+  static Topic *create(Handle *base,
+                       const std::string &topic_str,
+                       const Conf *conf,
+                       std::string &errstr);
+
+  virtual ~Topic() = 0;
+
+
+  /** @returns the topic name */
+  virtual std::string name() const = 0;
+
+  /**
+   * @returns true if \p partition is available for the topic (has leader).
+   * @warning \b MUST \b ONLY be called from within a
+   *          RdKafka::PartitionerCb callback.
+   */
+  virtual bool partition_available(int32_t partition) const = 0;
+
+  /**
+   * @brief Store offset \p offset + 1 for topic partition \p partition.
+   * The offset will be committed (written) to the broker (or file) according
+   * to \p auto.commit.interval.ms or next manual offset-less commit call.
+   *
+   * @deprecated This API lacks support for partition leader epochs, which makes
+   *             it at risk for unclean leader election log truncation issues.
+   *             Use KafkaConsumer::offsets_store() or
+   *             Message::offset_store() instead.
+   *
+   * @remark \c enable.auto.offset.store must be set to \c false when using
+   *         this API.
+   *
+   * @returns RdKafka::ERR_NO_ERROR on success or an error code if none of the
+   *          offsets could be stored.
+   */
+  virtual ErrorCode offset_store(int32_t partition, int64_t offset) = 0;
+
+  /**
+   * @brief Returns the underlying librdkafka C rd_kafka_topic_t handle.
+   *
+   * @warning Calling the C API on this handle is not recommended and there
+   *          is no official support for it, but for cases where the C++ API
+   *          does not provide the underlying functionality this C handle can be
+   *          used to interact directly with the core librdkafka API.
+   *
+   * @remark The lifetime of the returned pointer is the same as the Topic
+   *         object this method is called on.
+   *
+   * @remark Include <rdkafka/rdkafka.h> prior to including
+   *         <rdkafka/rdkafkacpp.h>
+   *
+   * @returns \c rd_kafka_topic_t*
+   */
+  virtual struct rd_kafka_topic_s *c_ptr() = 0;
+};
+
+
+/**@}*/
+
+
+/**
+ * @name Message object
+ * @{
+ *
+ */
+
+
+/**
+ * @brief Message timestamp object
+ *
+ * Represents the number of milliseconds since the epoch (UTC).
+ *
+ * The MessageTimestampType dictates the timestamp type or origin.
+ *
+ * @remark Requires Apache Kafka broker version >= 0.10.0
+ *
+ */
+
+class RD_EXPORT MessageTimestamp {
+ public:
+  /*! Message timestamp type */
+  enum MessageTimestampType {
+    MSG_TIMESTAMP_NOT_AVAILABLE,  /**< Timestamp not available */
+    MSG_TIMESTAMP_CREATE_TIME,    /**< Message creation time (source) */
+    MSG_TIMESTAMP_LOG_APPEND_TIME /**< Message log append time (broker) */
+  };
+
+  MessageTimestampType type; /**< Timestamp type */
+  int64_t timestamp;         /**< Milliseconds since epoch (UTC). */
+};
+
+
+/**
+ * @brief Headers object
+ *
+ * Represents message headers.
+ *
+ * https://cwiki.apache.org/confluence/display/KAFKA/KIP-82+-+Add+Record+Headers
+ *
+ * @remark Requires Apache Kafka >= 0.11.0 brokers
+ */
+class RD_EXPORT Headers {
+ public:
+  virtual ~Headers() = 0;
+
+  /**
+   * @brief Header object
+   *
+   * This object represents a single Header with a key value pair
+   * and an ErrorCode
+   *
+   * @remark dynamic allocation of this object is not supported.
+   */
+  class Header {
+   public:
+    /**
+     * @brief Header object to encapsulate a single Header
+     *
+     * @param key the string value for the header key
+     * @param value the bytes of the header value, or NULL
+     * @param value_size the length in bytes of the header value
+     *
+     * @remark key and value are copied.
+     *
+     */
+    Header(const std::string &key, const void *value, size_t value_size) :
+        key_(key), err_(ERR_NO_ERROR), value_size_(value_size) {
+      value_ = copy_value(value, value_size);
+    }
+
+    /**
+     * @brief Header object to encapsulate a single Header
+     *
+     * @param key the string value for the header key
+     * @param value the bytes of the header value
+     * @param value_size the length in bytes of the header value
+     * @param err the error code if one returned
+     *
+     * @remark The error code is used for when the Header is constructed
+     *         internally by using RdKafka::Headers::get_last which constructs
+     *         a Header encapsulating the ErrorCode in the process.
+     *         If err is set, the value and value_size fields will be undefined.
+     */
+    Header(const std::string &key,
+           const void *value,
+           size_t value_size,
+           const RdKafka::ErrorCode err) :
+        key_(key), err_(err), value_(NULL), value_size_(value_size) {
+      if (err == ERR_NO_ERROR)
+        value_ = copy_value(value, value_size);
+    }
+
+    /**
+     * @brief Copy constructor
+     *
+     * @param other Header to make a copy of.
+     */
+    Header(const Header &other) :
+        key_(other.key_), err_(other.err_), value_size_(other.value_size_) {
+      value_ = copy_value(other.value_, value_size_);
+    }
+
+    /**
+     * @brief Assignment operator
+     *
+     * @param other Header to make a copy of.
+     */
+    Header &operator=(const Header &other) {
+      if (&other == this) {
+        return *this;
+      }
+
+      key_        = other.key_;
+      err_        = other.err_;
+      value_size_ = other.value_size_;
+
+      if (value_ != NULL)
+        mem_free(value_);
+
+      value_ = copy_value(other.value_, value_size_);
+
+      return *this;
+    }
+
+    ~Header() {
+      if (value_ != NULL)
+        mem_free(value_);
+    }
+
+    /** @returns the key/name associated with this Header */
+    std::string key() const {
+      return key_;
+    }
+
+    /** @returns returns the binary value, or NULL */
+    const void *value() const {
+      return value_;
+    }
+
+    /** @returns returns the value casted to a nul-terminated C string,
+     *           or NULL. */
+    const char *value_string() const {
+      return static_cast<const char *>(value_);
+    }
+
+    /** @returns Value Size the length of the Value in bytes */
+    size_t value_size() const {
+      return value_size_;
+    }
+
+    /** @returns the error code of this Header (usually ERR_NO_ERROR) */
+    RdKafka::ErrorCode err() const {
+      return err_;
+    }
+
+   private:
+    char *copy_value(const void *value, size_t value_size) {
+      if (!value)
+        return NULL;
+
+      char *dest = (char *)mem_malloc(value_size + 1);
+      memcpy(dest, (const char *)value, value_size);
+      dest[value_size] = '\0';
+
+      return dest;
+    }
+
+    std::string key_;
+    RdKafka::ErrorCode err_;
+    char *value_;
+    size_t value_size_;
+    void *operator new(size_t); /* Prevent dynamic allocation */
+  };
+
+  /**
+   * @brief Create a new instance of the Headers object
+   *
+   * @returns an empty Headers list
+   */
+  static Headers *create();
+
+  /**
+   * @brief Create a new instance of the Headers object from a std::vector
+   *
+   * @param headers std::vector of RdKafka::Headers::Header objects.
+   *                The headers are copied, not referenced.
+   *
+   * @returns a Headers list from std::vector set to the size of the std::vector
+   */
+  static Headers *create(const std::vector<Header> &headers);
+
+  /**
+   * @brief Adds a Header to the end of the list.
+   *
+   * @param key header key/name
+   * @param value binary value, or NULL
+   * @param value_size size of the value
+   *
+   * @returns an ErrorCode signalling success or failure to add the header.
+   */
+  virtual ErrorCode add(const std::string &key,
+                        const void *value,
+                        size_t value_size) = 0;
+
+  /**
+   * @brief Adds a Header to the end of the list.
+   *
+   * Convenience method for adding a std::string as a value for the header.
+   *
+   * @param key header key/name
+   * @param value value string
+   *
+   * @returns an ErrorCode signalling success or failure to add the header.
+   */
+  virtual ErrorCode add(const std::string &key, const std::string &value) = 0;
+
+  /**
+   * @brief Adds a Header to the end of the list.
+   *
+   * This method makes a copy of the passed header.
+   *
+   * @param header Existing header to copy
+   *
+   * @returns an ErrorCode signalling success or failure to add the header.
+   */
+  virtual ErrorCode add(const Header &header) = 0;
+
+  /**
+   * @brief Removes all the Headers of a given key
+   *
+   * @param key header key/name to remove
+   *
+   * @returns An ErrorCode signalling a success or failure to remove the Header.
+   */
+  virtual ErrorCode remove(const std::string &key) = 0;
+
+  /**
+   * @brief Gets all of the Headers of a given key
+   *
+   * @param key header key/name
+   *
+   * @remark If duplicate keys exist this will return them all as a std::vector
+   *
+   * @returns a std::vector containing all the Headers of the given key.
+   */
+  virtual std::vector<Header> get(const std::string &key) const = 0;
+
+  /**
+   * @brief Gets the last occurrence of a Header of a given key
+   *
+   * @param key header key/name
+   *
+   * @remark This will only return the most recently added header
+   *
+   * @returns the Header if found, otherwise a Header with an err set to
+   *          ERR__NOENT.
+   */
+  virtual Header get_last(const std::string &key) const = 0;
+
+  /**
+   * @brief Returns all Headers
+   *
+   * @returns a std::vector containing all of the Headers
+   */
+  virtual std::vector<Header> get_all() const = 0;
+
+  /**
+   * @returns the number of headers.
+   */
+  virtual size_t size() const = 0;
+};
+
+
+/**
+ * @brief Message object
+ *
+ * This object represents either a single consumed or produced message,
+ * or an event (\p err() is set).
+ *
+ * An application must check RdKafka::Message::err() to see if the
+ * object is a proper message (error is RdKafka::ERR_NO_ERROR) or a
+ * an error event.
+ *
+ */
+class RD_EXPORT Message {
+ public:
+  /** @brief Message persistence status can be used by the application to
+   *         find out if a produced message was persisted in the topic log. */
+  enum Status {
+    /** Message was never transmitted to the broker, or failed with
+     *  an error indicating it was not written to the log.
+     *  Application retry risks ordering, but not duplication. */
+    MSG_STATUS_NOT_PERSISTED = 0,
+
+    /** Message was transmitted to broker, but no acknowledgement was
+     *  received.
+     *  Application retry risks ordering and duplication. */
+    MSG_STATUS_POSSIBLY_PERSISTED = 1,
+
+    /** Message was written to the log and fully acknowledged.
+     *  No reason for application to retry.
+     *  Note: this value should only be trusted with \c acks=all. */
+    MSG_STATUS_PERSISTED = 2,
+  };
+
+  /**
+   * @brief Accessor functions*
+   * @remark Not all fields are present in all types of callbacks.
+   */
+
+  /** @returns The error string if object represent an error event,
+   *           else an empty string. */
+  virtual std::string errstr() const = 0;
+
+  /** @returns The error code if object represents an error event, else 0. */
+  virtual ErrorCode err() const = 0;
+
+  /** @returns the RdKafka::Topic object for a message (if applicable),
+   *            or NULL if a corresponding RdKafka::Topic object has not been
+   *            explicitly created with RdKafka::Topic::create().
+   *            In this case use topic_name() instead. */
+  virtual Topic *topic() const = 0;
+
+  /** @returns Topic name (if applicable, else empty string) */
+  virtual std::string topic_name() const = 0;
+
+  /** @returns Partition (if applicable) */
+  virtual int32_t partition() const = 0;
+
+  /** @returns Message payload (if applicable) */
+  virtual void *payload() const = 0;
+
+  /** @returns Message payload length (if applicable) */
+  virtual size_t len() const = 0;
+
+  /** @returns Message key as string (if applicable) */
+  virtual const std::string *key() const = 0;
+
+  /** @returns Message key as void pointer  (if applicable) */
+  virtual const void *key_pointer() const = 0;
+
+  /** @returns Message key's binary length (if applicable) */
+  virtual size_t key_len() const = 0;
+
+  /** @returns Message or error offset (if applicable) */
+  virtual int64_t offset() const = 0;
+
+  /** @returns Message timestamp (if applicable) */
+  virtual MessageTimestamp timestamp() const = 0;
+
+  /** @returns The \p msg_opaque as provided to RdKafka::Producer::produce() */
+  virtual void *msg_opaque() const = 0;
+
+  virtual ~Message() = 0;
+
+  /** @returns the latency in microseconds for a produced message measured
+   *           from the produce() call, or -1 if latency is not available. */
+  virtual int64_t latency() const = 0;
+
+  /**
+   * @brief Returns the underlying librdkafka C rd_kafka_message_t handle.
+   *
+   * @warning Calling the C API on this handle is not recommended and there
+   *          is no official support for it, but for cases where the C++ API
+   *          does not provide the underlying functionality this C handle can be
+   *          used to interact directly with the core librdkafka API.
+   *
+   * @remark The lifetime of the returned pointer is the same as the Message
+   *         object this method is called on.
+   *
+   * @remark Include <rdkafka/rdkafka.h> prior to including
+   *         <rdkafka/rdkafkacpp.h>
+   *
+   * @returns \c rd_kafka_message_t*
+   */
+  virtual struct rd_kafka_message_s *c_ptr() = 0;
+
+  /**
+   * @brief Returns the message's persistence status in the topic log.
+   */
+  virtual Status status() const = 0;
+
+  /** @returns the Headers instance for this Message, or NULL if there
+   *  are no headers.
+   *
+   * @remark The lifetime of the Headers are the same as the Message. */
+  virtual RdKafka::Headers *headers() = 0;
+
+  /** @returns the Headers instance for this Message (if applicable).
+   *  If NULL is returned the reason is given in \p err, which
+   *  is either ERR__NOENT if there were no headers, or another
+   *  error code if header parsing failed.
+   *
+   * @remark The lifetime of the Headers are the same as the Message. */
+  virtual RdKafka::Headers *headers(RdKafka::ErrorCode *err) = 0;
+
+  /** @returns the broker id of the broker the message was produced to or
+   *           fetched from, or -1 if not known/applicable. */
+  virtual int32_t broker_id() const = 0;
+
+  /** @returns the message's partition leader epoch at the time the message was
+   *           fetched and if known, else -1. */
+  virtual int32_t leader_epoch() const = 0;
+
+  /**
+   * @brief Store offset +1 for the consumed message.
+   *
+   * The message offset + 1 will be committed to broker according
+   * to \c `auto.commit.interval.ms` or manual offset-less commit()
+   *
+   * @warning This method may only be called for partitions that are currently
+   *          assigned.
+   *          Non-assigned partitions will fail with ERR__STATE.
+   *
+   * @warning Avoid storing offsets after calling seek() (et.al) as
+   *          this may later interfere with resuming a paused partition, instead
+   *          store offsets prior to calling seek.
+   *
+   * @remark \c `enable.auto.offset.store` must be set to "false" when using
+   *         this API.
+   *
+   * @returns NULL on success or an error object on failure.
+   */
+  virtual Error *offset_store() = 0;
+};
+
+/**@}*/
+
+
+/**
+ * @name Queue interface
+ * @{
+ *
+ */
+
+
+/**
+ * @brief Queue interface
+ *
+ * Create a new message queue.  Message queues allows the application
+ * to re-route consumed messages from multiple topic+partitions into
+ * one single queue point.  This queue point, containing messages from
+ * a number of topic+partitions, may then be served by a single
+ * consume() method, rather than one per topic+partition combination.
+ *
+ * See the RdKafka::Consumer::start(), RdKafka::Consumer::consume(), and
+ * RdKafka::Consumer::consume_callback() methods that take a queue as the first
+ * parameter for more information.
+ */
+class RD_EXPORT Queue {
+ public:
+  /**
+   * @brief Create Queue object
+   */
+  static Queue *create(Handle *handle);
+
+  /**
+   * @brief Forward/re-route queue to \p dst.
+   * If \p dst is \c NULL, the forwarding is removed.
+   *
+   * The internal refcounts for both queues are increased.
+   *
+   * @remark Regardless of whether \p dst is NULL or not, after calling this
+   *         function, \p src will not forward it's fetch queue to the consumer
+   *         queue.
+   */
+  virtual ErrorCode forward(Queue *dst) = 0;
+
+
+  /**
+   * @brief Consume message or get error event from the queue.
+   *
+   * @remark Use \c delete to free the message.
+   *
+   * @returns One of:
+   *  - proper message (RdKafka::Message::err() is ERR_NO_ERROR)
+   *  - error event (RdKafka::Message::err() is != ERR_NO_ERROR)
+   *  - timeout due to no message or event in \p timeout_ms
+   *    (RdKafka::Message::err() is ERR__TIMED_OUT)
+   */
+  virtual Message *consume(int timeout_ms) = 0;
+
+  /**
+   * @brief Poll queue, serving any enqueued callbacks.
+   *
+   * @remark Must NOT be used for queues containing messages.
+   *
+   * @returns the number of events served or 0 on timeout.
+   */
+  virtual int poll(int timeout_ms) = 0;
+
+  virtual ~Queue() = 0;
+
+  /**
+   * @brief Enable IO event triggering for queue.
+   *
+   * To ease integration with IO based polling loops this API
+   * allows an application to create a separate file-descriptor
+   * that librdkafka will write \p payload (of size \p size) to
+   * whenever a new element is enqueued on a previously empty queue.
+   *
+   * To remove event triggering call with \p fd = -1.
+   *
+   * librdkafka will maintain a copy of the \p payload.
+   *
+   * @remark When using forwarded queues the IO event must only be enabled
+   *         on the final forwarded-to (destination) queue.
+   */
+  virtual void io_event_enable(int fd, const void *payload, size_t size) = 0;
+};
+
+/**@}*/
+
+/**
+ * @name ConsumerGroupMetadata
+ * @{
+ *
+ */
+/**
+ * @brief ConsumerGroupMetadata holds a consumer instance's group
+ *        metadata state.
+ *
+ * This class currently does not have any public methods.
+ */
+class RD_EXPORT ConsumerGroupMetadata {
+ public:
+  virtual ~ConsumerGroupMetadata() = 0;
+};
+
+/**@}*/
+
+/**
+ * @name KafkaConsumer
+ * @{
+ *
+ */
+
+
+/**
+ * @brief High-level KafkaConsumer (for brokers 0.9 and later)
+ *
+ * @remark Requires Apache Kafka >= 0.9.0 brokers
+ *
+ * Currently supports the \c range and \c roundrobin partition assignment
+ * strategies (see \c partition.assignment.strategy)
+ */
+class RD_EXPORT KafkaConsumer : public virtual Handle {
+ public:
+  /**
+   * @brief Creates a KafkaConsumer.
+   *
+   * The \p conf object must have \c group.id set to the consumer group to join.
+   *
+   * Use RdKafka::KafkaConsumer::close() to shut down the consumer.
+   *
+   * @sa RdKafka::RebalanceCb
+   * @sa CONFIGURATION.md for \c group.id, \c session.timeout.ms,
+   *     \c partition.assignment.strategy, etc.
+   */
+  static KafkaConsumer *create(const Conf *conf, std::string &errstr);
+
+  virtual ~KafkaConsumer() = 0;
+
+
+  /** @brief Returns the current partition assignment as set by
+   *         RdKafka::KafkaConsumer::assign() */
+  virtual ErrorCode assignment(
+      std::vector<RdKafka::TopicPartition *> &partitions) = 0;
+
+  /** @brief Returns the current subscription as set by
+   *         RdKafka::KafkaConsumer::subscribe() */
+  virtual ErrorCode subscription(std::vector<std::string> &topics) = 0;
+
+  /**
+   * @brief Update the subscription set to \p topics.
+   *
+   * Any previous subscription will be unassigned and  unsubscribed first.
+   *
+   * The subscription set denotes the desired topics to consume and this
+   * set is provided to the partition assignor (one of the elected group
+   * members) for all clients which then uses the configured
+   * \c partition.assignment.strategy to assign the subscription sets's
+   * topics's partitions to the consumers, depending on their subscription.
+   *
+   * The result of such an assignment is a rebalancing which is either
+   * handled automatically in librdkafka or can be overridden by the application
+   * by providing a RdKafka::RebalanceCb.
+   *
+   * The rebalancing passes the assigned partition set to
+   * RdKafka::KafkaConsumer::assign() to update what partitions are actually
+   * being fetched by the KafkaConsumer.
+   *
+   * Regex pattern matching automatically performed for topics prefixed
+   * with \c \"^\" (e.g. \c \"^myPfx[0-9]_.*\"
+   *
+   * @remark A consumer error will be raised for each unavailable topic in the
+   *  \p topics. The error will be ERR_UNKNOWN_TOPIC_OR_PART
+   *  for non-existent topics, and
+   *  ERR_TOPIC_AUTHORIZATION_FAILED for unauthorized topics.
+   *  The consumer error will be raised through consume() (et.al.)
+   *  with the \c RdKafka::Message::err() returning one of the
+   *  error codes mentioned above.
+   *  The subscribe function itself is asynchronous and will not return
+   *  an error on unavailable topics.
+   *
+   * @returns an error if the provided list of topics is invalid.
+   */
+  virtual ErrorCode subscribe(const std::vector<std::string> &topics) = 0;
+
+  /** @brief Unsubscribe from the current subscription set. */
+  virtual ErrorCode unsubscribe() = 0;
+
+  /**
+   *  @brief Update the assignment set to \p partitions.
+   *
+   * The assignment set is the set of partitions actually being consumed
+   * by the KafkaConsumer.
+   */
+  virtual ErrorCode assign(const std::vector<TopicPartition *> &partitions) = 0;
+
+  /**
+   * @brief Stop consumption and remove the current assignment.
+   */
+  virtual ErrorCode unassign() = 0;
+
+  /**
+   * @brief Consume message or get error event, triggers callbacks.
+   *
+   * Will automatically call registered callbacks for any such queued events,
+   * including RdKafka::RebalanceCb, RdKafka::EventCb, RdKafka::OffsetCommitCb,
+   * etc.
+   *
+   * @remark Use \c delete to free the message.
+   *
+   * @remark  An application should make sure to call consume() at regular
+   *          intervals, even if no messages are expected, to serve any
+   *          queued callbacks waiting to be called. This is especially
+   *          important when a RebalanceCb has been registered as it needs
+   *          to be called and handled properly to synchronize internal
+   *          consumer state.
+   *
+   * @remark Application MUST NOT call \p poll() on KafkaConsumer objects.
+   *
+   * @returns One of:
+   *  - proper message (RdKafka::Message::err() is ERR_NO_ERROR)
+   *  - error event (RdKafka::Message::err() is != ERR_NO_ERROR)
+   *  - timeout due to no message or event in \p timeout_ms
+   *    (RdKafka::Message::err() is ERR__TIMED_OUT)
+   */
+  virtual Message *consume(int timeout_ms) = 0;
+
+  /**
+   * @brief Commit offsets for the current assignment.
+   *
+   * @remark This is the synchronous variant that blocks until offsets
+   *         are committed or the commit fails (see return value).
+   *
+   * @remark If a RdKafka::OffsetCommitCb callback is registered it will
+   *         be called with commit details on a future call to
+   *         RdKafka::KafkaConsumer::consume()
+
+   *
+   * @returns ERR_NO_ERROR or error code.
+   */
+  virtual ErrorCode commitSync() = 0;
+
+  /**
+   * @brief Asynchronous version of RdKafka::KafkaConsumer::CommitSync()
+   *
+   * @sa RdKafka::KafkaConsumer::commitSync()
+   */
+  virtual ErrorCode commitAsync() = 0;
+
+  /**
+   * @brief Commit offset for a single topic+partition based on \p message
+   *
+   * @remark The offset committed will be the message's offset + 1.
+   *
+   * @remark This is the synchronous variant.
+   *
+   * @sa RdKafka::KafkaConsumer::commitSync()
+   */
+  virtual ErrorCode commitSync(Message *message) = 0;
+
+  /**
+   * @brief Commit offset for a single topic+partition based on \p message
+   *
+   * @remark The offset committed will be the message's offset + 1.
+   *
+   * @remark This is the asynchronous variant.
+   *
+   * @sa RdKafka::KafkaConsumer::commitSync()
+   */
+  virtual ErrorCode commitAsync(Message *message) = 0;
+
+  /**
+   * @brief Commit offsets for the provided list of partitions.
+   *
+   * @remark The \c .offset of the partitions in \p offsets should be the
+   *         offset where consumption will resume, i.e., the last
+   *         processed offset + 1.
+   *
+   * @remark This is the synchronous variant.
+   */
+  virtual ErrorCode commitSync(std::vector<TopicPartition *> &offsets) = 0;
+
+  /**
+   * @brief Commit offset for the provided list of partitions.
+   *
+   * @remark The \c .offset of the partitions in \p offsets should be the
+   *         offset where consumption will resume, i.e., the last
+   *         processed offset + 1.
+   *
+   * @remark This is the asynchronous variant.
+   */
+  virtual ErrorCode commitAsync(
+      const std::vector<TopicPartition *> &offsets) = 0;
+
+  /**
+   * @brief Commit offsets for the current assignment.
+   *
+   * @remark This is the synchronous variant that blocks until offsets
+   *         are committed or the commit fails (see return value).
+   *
+   * @remark The provided callback will be called from this function.
+   *
+   * @returns ERR_NO_ERROR or error code.
+   */
+  virtual ErrorCode commitSync(OffsetCommitCb *offset_commit_cb) = 0;
+
+  /**
+   * @brief Commit offsets for the provided list of partitions.
+   *
+   * @remark This is the synchronous variant that blocks until offsets
+   *         are committed or the commit fails (see return value).
+   *
+   * @remark The provided callback will be called from this function.
+   *
+   * @returns ERR_NO_ERROR or error code.
+   */
+  virtual ErrorCode commitSync(std::vector<TopicPartition *> &offsets,
+                               OffsetCommitCb *offset_commit_cb) = 0;
+
+
+
+  /**
+   * @brief Retrieve committed offsets for topics+partitions.
+   *
+   * @returns ERR_NO_ERROR on success in which case the
+   *          \p offset or \p err field of each \p partitions' element is filled
+   *          in with the stored offset, or a partition specific error.
+   *          Else returns an error code.
+   */
+  virtual ErrorCode committed(std::vector<TopicPartition *> &partitions,
+                              int timeout_ms) = 0;
+
+  /**
+   * @brief Retrieve current positions (offsets) for topics+partitions.
+   *
+   * @returns ERR_NO_ERROR on success in which case the
+   *          \p offset or \p err field of each \p partitions' element is filled
+   *          in with the stored offset, or a partition specific error.
+   *          Else returns an error code.
+   */
+  virtual ErrorCode position(std::vector<TopicPartition *> &partitions) = 0;
+
+
+  /**
+   * For pausing and resuming consumption, see
+   * @sa RdKafka::Handle::pause() and RdKafka::Handle::resume()
+   */
+
+
+  /**
+   * @brief Close and shut down the consumer.
+   *
+   * This call will block until the following operations are finished:
+   *  - Trigger a local rebalance to void the current assignment (if any).
+   *  - Stop consumption for current assignment (if any).
+   *  - Commit offsets (if any).
+   *  - Leave group (if applicable).
+   *
+   * The maximum blocking time is roughly limited to session.timeout.ms.
+   *
+   * @remark Callbacks, such as RdKafka::RebalanceCb and
+   *         RdKafka::OffsetCommitCb, etc, may be called.
+   *
+   * @remark The consumer object must later be freed with \c delete
+   */
+  virtual ErrorCode close() = 0;
+
+
+  /**
+   * @brief Seek consumer for topic+partition to offset which is either an
+   *        absolute or logical offset.
+   *
+   * If \p timeout_ms is not 0 the call will wait this long for the
+   * seek to be performed. If the timeout is reached the internal state
+   * will be unknown and this function returns `ERR__TIMED_OUT`.
+   * If \p timeout_ms is 0 it will initiate the seek but return
+   * immediately without any error reporting (e.g., async).
+   *
+   * This call triggers a fetch queue barrier flush.
+   *
+   * @remark Consumption for the given partition must have started for the
+   *         seek to work. Use assign() to set the starting offset.
+   *
+   * @returns an ErrorCode to indicate success or failure.
+   */
+  virtual ErrorCode seek(const TopicPartition &partition, int timeout_ms) = 0;
+
+
+  /**
+   * @brief Store offset \p offset for topic partition \p partition.
+   * The offset will be committed (written) to the offset store according
+   * to \p auto.commit.interval.ms or the next manual offset-less commit*()
+   *
+   * Per-partition success/error status propagated through TopicPartition.err()
+   *
+   * @remark The \c .offset field is stored as is, it will NOT be + 1.
+   *
+   * @remark \c enable.auto.offset.store must be set to \c false when using
+   *         this API.
+   *
+   * @remark The leader epoch, if set, will be used to fence outdated partition
+   *         leaders. See TopicPartition::set_leader_epoch().
+   *
+   * @returns RdKafka::ERR_NO_ERROR on success, or
+   *          RdKafka::ERR___UNKNOWN_PARTITION if none of the offsets could
+   *          be stored, or
+   *          RdKafka::ERR___INVALID_ARG if \c enable.auto.offset.store is true.
+   */
+  virtual ErrorCode offsets_store(std::vector<TopicPartition *> &offsets) = 0;
+
+
+  /**
+   * @returns the current consumer group metadata associated with this consumer,
+   *          or NULL if the consumer is configured with a \c group.id.
+   *          This metadata object should be passed to the transactional
+   *          producer's RdKafka::Producer::send_offsets_to_transaction() API.
+   *
+   * @remark The returned object must be deleted by the application.
+   *
+   * @sa RdKafka::Producer::send_offsets_to_transaction()
+   */
+  virtual ConsumerGroupMetadata *groupMetadata() = 0;
+
+
+  /** @brief Check whether the consumer considers the current assignment to
+   *         have been lost involuntarily. This method is only applicable for
+   *         use with a subscribing consumer. Assignments are revoked
+   *         immediately when determined to have been lost, so this method is
+   *         only useful within a rebalance callback. Partitions that have
+   *         been lost may already be owned by other members in the group and
+   *         therefore commiting offsets, for example, may fail.
+   *
+   * @remark Calling assign(), incremental_assign() or incremental_unassign()
+   *         resets this flag.
+   *
+   * @returns Returns true if the current partition assignment is considered
+   *          lost, false otherwise.
+   */
+  virtual bool assignment_lost() = 0;
+
+  /**
+   * @brief The rebalance protocol currently in use. This will be
+   *        "NONE" if the consumer has not (yet) joined a group, else it will
+   *        match the rebalance protocol ("EAGER", "COOPERATIVE") of the
+   *        configured and selected assignor(s). All configured
+   *        assignors must have the same protocol type, meaning
+   *        online migration of a consumer group from using one
+   *        protocol to another (in particular upgading from EAGER
+   *        to COOPERATIVE) without a restart is not currently
+   *        supported.
+   *
+   * @returns an empty string on error, or one of
+   *          "NONE", "EAGER", "COOPERATIVE" on success.
+   */
+
+  virtual std::string rebalance_protocol() = 0;
+
+
+  /**
+   * @brief Incrementally add \p partitions to the current assignment.
+   *
+   * If a COOPERATIVE assignor (i.e. incremental rebalancing) is being used,
+   * this method should be used in a rebalance callback to adjust the current
+   * assignment appropriately in the case where the rebalance type is
+   * ERR__ASSIGN_PARTITIONS. The application must pass the partition list
+   * passed to the callback (or a copy of it), even if the list is empty.
+   * This method may also be used outside the context of a rebalance callback.
+   *
+   * @returns NULL on success, or an error object if the operation was
+   *          unsuccessful.
+   *
+   * @remark The returned object must be deleted by the application.
+   */
+  virtual Error *incremental_assign(
+      const std::vector<TopicPartition *> &partitions) = 0;
+
+
+  /**
+   * @brief Incrementally remove \p partitions from the current assignment.
+   *
+   * If a COOPERATIVE assignor (i.e. incremental rebalancing) is being used,
+   * this method should be used in a rebalance callback to adjust the current
+   * assignment appropriately in the case where the rebalance type is
+   * ERR__REVOKE_PARTITIONS. The application must pass the partition list
+   * passed to the callback (or a copy of it), even if the list is empty.
+   * This method may also be used outside the context of a rebalance callback.
+   *
+   * @returns NULL on success, or an error object if the operation was
+   *          unsuccessful.
+   *
+   * @remark The returned object must be deleted by the application.
+   */
+  virtual Error *incremental_unassign(
+      const std::vector<TopicPartition *> &partitions) = 0;
+
+  /**
+   * @brief Close and shut down the consumer.
+   *
+   * Performs the same actions as RdKafka::KafkaConsumer::close() but in a
+   * background thread.
+   *
+   * Rebalance events/callbacks (etc) will be forwarded to the
+   * application-provided \p queue. The application must poll this queue until
+   * RdKafka::KafkaConsumer::closed() returns true.
+   *
+   * @remark Depending on consumer group join state there may or may not be
+   *         rebalance events emitted on \p rkqu.
+   *
+   * @returns an error object if the consumer close failed, else NULL.
+   *
+   * @sa RdKafka::KafkaConsumer::closed()
+   */
+  virtual Error *close(Queue *queue) = 0;
+
+
+  /** @returns true if the consumer is closed, else 0.
+   *
+   * @sa RdKafka::KafkaConsumer::close()
+   */
+  virtual bool closed() = 0;
+};
+
+
+/**@}*/
+
+
+/**
+ * @name Simple Consumer (legacy)
+ * @{
+ *
+ */
+
+/**
+ * @brief Simple Consumer (legacy)
+ *
+ * A simple non-balanced, non-group-aware, consumer.
+ */
+class RD_EXPORT Consumer : public virtual Handle {
+ public:
+  /**
+   * @brief Creates a new Kafka consumer handle.
+   *
+   * \p conf is an optional object that will be used instead of the default
+   * configuration.
+   * The \p conf object is reusable after this call.
+   *
+   * @returns the new handle on success or NULL on error in which case
+   * \p errstr is set to a human readable error message.
+   */
+  static Consumer *create(const Conf *conf, std::string &errstr);
+
+  virtual ~Consumer() = 0;
+
+
+  /**
+   * @brief Start consuming messages for topic and \p partition
+   * at offset \p offset which may either be a proper offset (0..N)
+   * or one of the the special offsets: \p OFFSET_BEGINNING or \p OFFSET_END.
+   *
+   * rdkafka will attempt to keep \p queued.min.messages (config property)
+   * messages in the local queue by repeatedly fetching batches of messages
+   * from the broker until the threshold is reached.
+   *
+   * The application shall use one of the \p ..->consume*() functions
+   * to consume messages from the local queue, each kafka message being
+   * represented as a `RdKafka::Message *` object.
+   *
+   * \p ..->start() must not be called multiple times for the same
+   * topic and partition without stopping consumption first with
+   * \p ..->stop().
+   *
+   * @returns an ErrorCode to indicate success or failure.
+   */
+  virtual ErrorCode start(Topic *topic, int32_t partition, int64_t offset) = 0;
+
+  /**
+   * @brief Start consuming messages for topic and \p partition on
+   *        queue \p queue.
+   *
+   * @sa RdKafka::Consumer::start()
+   */
+  virtual ErrorCode start(Topic *topic,
+                          int32_t partition,
+                          int64_t offset,
+                          Queue *queue) = 0;
+
+  /**
+   * @brief Stop consuming messages for topic and \p partition, purging
+   *        all messages currently in the local queue.
+   *
+   * The application needs to be stop all consumers before destroying
+   * the Consumer handle.
+   *
+   * @returns an ErrorCode to indicate success or failure.
+   */
+  virtual ErrorCode stop(Topic *topic, int32_t partition) = 0;
+
+  /**
+   * @brief Seek consumer for topic+partition to \p offset which is either an
+   *        absolute or logical offset.
+   *
+   * If \p timeout_ms is not 0 the call will wait this long for the
+   * seek to be performed. If the timeout is reached the internal state
+   * will be unknown and this function returns `ERR__TIMED_OUT`.
+   * If \p timeout_ms is 0 it will initiate the seek but return
+   * immediately without any error reporting (e.g., async).
+   *
+   * This call triggers a fetch queue barrier flush.
+   *
+   * @returns an ErrorCode to indicate success or failure.
+   */
+  virtual ErrorCode seek(Topic *topic,
+                         int32_t partition,
+                         int64_t offset,
+                         int timeout_ms) = 0;
+
+  /**
+   * @brief Consume a single message from \p topic and \p partition.
+   *
+   * \p timeout_ms is maximum amount of time to wait for a message to be
+   * received.
+   * Consumer must have been previously started with \p ..->start().
+   *
+   * @returns a Message object, the application needs to check if message
+   * is an error or a proper message RdKafka::Message::err() and checking for
+   * \p ERR_NO_ERROR.
+   *
+   * The message object must be destroyed when the application is done with it.
+   *
+   * Errors (in RdKafka::Message::err()):
+   *  - ERR__TIMED_OUT - \p timeout_ms was reached with no new messages fetched.
+   *  - ERR__PARTITION_EOF - End of partition reached, not an error.
+   */
+  virtual Message *consume(Topic *topic, int32_t partition, int timeout_ms) = 0;
+
+  /**
+   * @brief Consume a single message from the specified queue.
+   *
+   * \p timeout_ms is maximum amount of time to wait for a message to be
+   * received.
+   * Consumer must have been previously started on the queue with
+   * \p ..->start().
+   *
+   * @returns a Message object, the application needs to check if message
+   * is an error or a proper message \p Message->err() and checking for
+   * \p ERR_NO_ERROR.
+   *
+   * The message object must be destroyed when the application is done with it.
+   *
+   * Errors (in RdKafka::Message::err()):
+   *   - ERR__TIMED_OUT - \p timeout_ms was reached with no new messages fetched
+   *
+   * Note that Message->topic() may be nullptr after certain kinds of
+   * errors, so applications should check that it isn't null before
+   * dereferencing it.
+   */
+  virtual Message *consume(Queue *queue, int timeout_ms) = 0;
+
+  /**
+   * @brief Consumes messages from \p topic and \p partition, calling
+   *        the provided callback for each consumed messsage.
+   *
+   * \p consume_callback() provides higher throughput performance
+   * than \p consume().
+   *
+   * \p timeout_ms is the maximum amount of time to wait for one or
+   * more messages to arrive.
+   *
+   * The provided \p consume_cb instance has its \p consume_cb function
+   * called for every message received.
+   *
+   * The \p opaque argument is passed to the \p consume_cb as \p opaque.
+   *
+   * @returns the number of messages processed or -1 on error.
+   *
+   * @sa RdKafka::Consumer::consume()
+   */
+  virtual int consume_callback(Topic *topic,
+                               int32_t partition,
+                               int timeout_ms,
+                               ConsumeCb *consume_cb,
+                               void *opaque) = 0;
+
+  /**
+   * @brief Consumes messages from \p queue, calling the provided callback for
+   *        each consumed messsage.
+   *
+   * @sa RdKafka::Consumer::consume_callback()
+   */
+  virtual int consume_callback(Queue *queue,
+                               int timeout_ms,
+                               RdKafka::ConsumeCb *consume_cb,
+                               void *opaque) = 0;
+
+  /**
+   * @brief Converts an offset into the logical offset from the tail of a topic.
+   *
+   * \p offset is the (positive) number of items from the end.
+   *
+   * @returns the logical offset for message \p offset from the tail, this value
+   *          may be passed to Consumer::start, et.al.
+   * @remark The returned logical offset is specific to librdkafka.
+   */
+  static int64_t OffsetTail(int64_t offset);
+};
+
+/**@}*/
+
+
+/**
+ * @name Producer
+ * @{
+ *
+ */
+
+
+/**
+ * @brief Producer
+ */
+class RD_EXPORT Producer : public virtual Handle {
+ public:
+  /**
+   * @brief Creates a new Kafka producer handle.
+   *
+   * \p conf is an optional object that will be used instead of the default
+   * configuration.
+   * The \p conf object is reusable after this call.
+   *
+   * @returns the new handle on success or NULL on error in which case
+   *          \p errstr is set to a human readable error message.
+   */
+  static Producer *create(const Conf *conf, std::string &errstr);
+
+
+  virtual ~Producer() = 0;
+
+  /**
+   * @brief RdKafka::Producer::produce() \p msgflags
+   *
+   * These flags are optional.
+   */
+  enum {
+    RK_MSG_FREE = 0x1, /**< rdkafka will free(3) \p payload
+                        * when it is done with it.
+                        * Mutually exclusive with RK_MSG_COPY. */
+    RK_MSG_COPY = 0x2, /**< the \p payload data will be copied
+                        * and the \p payload pointer will not
+                        * be used by rdkafka after the
+                        * call returns.
+                        * Mutually exclusive with RK_MSG_FREE. */
+    RK_MSG_BLOCK = 0x4 /**< Block produce*() on message queue
+                        *   full.
+                        *   WARNING:
+                        *   If a delivery report callback
+                        *   is used the application MUST
+                        *   call rd_kafka_poll() (or equiv.)
+                        *   to make sure delivered messages
+                        *   are drained from the internal
+                        *   delivery report queue.
+                        *   Failure to do so will result
+                        *   in indefinately blocking on
+                        *   the produce() call when the
+                        *   message queue is full.
+                        */
+
+
+  /**@cond NO_DOC*/
+  /* For backwards compatibility: */
+#ifndef MSG_COPY /* defined in sys/msg.h */
+    ,            /** this comma must exist betwen
+                  *  RK_MSG_BLOCK and MSG_FREE
+                  */
+    MSG_FREE = RK_MSG_FREE,
+    MSG_COPY = RK_MSG_COPY
+#endif
+    /**@endcond*/
+  };
+
+  /**
+   * @brief Produce and send a single message to broker.
+   *
+   * This is an asynch non-blocking API.
+   *
+   * \p partition is the target partition, either:
+   *   - RdKafka::Topic::PARTITION_UA (unassigned) for
+   *     automatic partitioning using the topic's partitioner function, or
+   *   - a fixed partition (0..N)
+   *
+   * \p msgflags is zero or more of the following flags OR:ed together:
+   *    RK_MSG_BLOCK - block \p produce*() call if
+   *                   \p queue.buffering.max.messages or
+   *                   \p queue.buffering.max.kbytes are exceeded.
+   *                   Messages are considered in-queue from the point they
+   *                   are accepted by produce() until their corresponding
+   *                   delivery report callback/event returns.
+   *                   It is thus a requirement to call
+   *                   poll() (or equiv.) from a separate
+   *                   thread when RK_MSG_BLOCK is used.
+   *                   See WARNING on \c RK_MSG_BLOCK above.
+   *    RK_MSG_FREE - rdkafka will free(3) \p payload when it is done with it.
+   *    RK_MSG_COPY - the \p payload data will be copied and the \p payload
+   *               pointer will not be used by rdkafka after the
+   *               call returns.
+   *
+   *  NOTE: RK_MSG_FREE and RK_MSG_COPY are mutually exclusive.
+   *
+   *  If the function returns an error code and RK_MSG_FREE was specified, then
+   *  the memory associated with the payload is still the caller's
+   *  responsibility.
+   *
+   * \p payload is the message payload of size \p len bytes.
+   *
+   * \p key is an optional message key, if non-NULL it
+   * will be passed to the topic partitioner as well as be sent with the
+   * message to the broker and passed on to the consumer.
+   *
+   * \p msg_opaque is an optional application-provided per-message opaque
+   * pointer that will provided in the delivery report callback (\p dr_cb) for
+   * referencing this message.
+   *
+   * @returns an ErrorCode to indicate success or failure:
+   *  - ERR_NO_ERROR           - message successfully enqueued for transmission.
+   *
+   *  - ERR__QUEUE_FULL        - maximum number of outstanding messages has been
+   *                             reached: \c queue.buffering.max.message
+   *
+   *  - ERR_MSG_SIZE_TOO_LARGE - message is larger than configured max size:
+   *                            \c messages.max.bytes
+   *
+   *  - ERR__UNKNOWN_PARTITION - requested \p partition is unknown in the
+   *                           Kafka cluster.
+   *
+   *  - ERR__UNKNOWN_TOPIC     - topic is unknown in the Kafka cluster.
+   */
+  virtual ErrorCode produce(Topic *topic,
+                            int32_t partition,
+                            int msgflags,
+                            void *payload,
+                            size_t len,
+                            const std::string *key,
+                            void *msg_opaque) = 0;
+
+  /**
+   * @brief Variant produce() that passes the key as a pointer and length
+   *        instead of as a const std::string *.
+   */
+  virtual ErrorCode produce(Topic *topic,
+                            int32_t partition,
+                            int msgflags,
+                            void *payload,
+                            size_t len,
+                            const void *key,
+                            size_t key_len,
+                            void *msg_opaque) = 0;
+
+  /**
+   * @brief produce() variant that takes topic as a string (no need for
+   *        creating a Topic object), and also allows providing the
+   *        message timestamp (milliseconds since beginning of epoch, UTC).
+   *        Otherwise identical to produce() above.
+   */
+  virtual ErrorCode produce(const std::string topic_name,
+                            int32_t partition,
+                            int msgflags,
+                            void *payload,
+                            size_t len,
+                            const void *key,
+                            size_t key_len,
+                            int64_t timestamp,
+                            void *msg_opaque) = 0;
+
+  /**
+   * @brief produce() variant that that allows for Header support on produce
+   *        Otherwise identical to produce() above.
+   *
+   * @warning The \p headers will be freed/deleted if the produce() call
+   *          succeeds, or left untouched if produce() fails.
+   */
+  virtual ErrorCode produce(const std::string topic_name,
+                            int32_t partition,
+                            int msgflags,
+                            void *payload,
+                            size_t len,
+                            const void *key,
+                            size_t key_len,
+                            int64_t timestamp,
+                            RdKafka::Headers *headers,
+                            void *msg_opaque) = 0;
+
+
+  /**
+   * @brief Variant produce() that accepts vectors for key and payload.
+   *        The vector data will be copied.
+   */
+  virtual ErrorCode produce(Topic *topic,
+                            int32_t partition,
+                            const std::vector<char> *payload,
+                            const std::vector<char> *key,
+                            void *msg_opaque) = 0;
+
+
+  /**
+   * @brief Wait until all outstanding produce requests, et.al, are completed.
+   *        This should typically be done prior to destroying a producer
+   * instance to make sure all queued and in-flight produce requests are
+   * completed before terminating.
+   *
+   * @remark The \c linger.ms time will be ignored for the duration of the call,
+   *         queued messages will be sent to the broker as soon as possible.
+   *
+   * @remark This function will call Producer::poll() and thus
+   *         trigger callbacks.
+   *
+   * @returns ERR__TIMED_OUT if \p timeout_ms was reached before all
+   *          outstanding requests were completed, else ERR_NO_ERROR
+   */
+  virtual ErrorCode flush(int timeout_ms) = 0;
+
+
+  /**
+   * @brief Purge messages currently handled by the producer instance.
+   *
+   * @param purge_flags tells which messages should be purged and how.
+   *
+   * The application will need to call Handle::poll() or Producer::flush()
+   * afterwards to serve the delivery report callbacks of the purged messages.
+   *
+   * Messages purged from internal queues fail with the delivery report
+   * error code set to ERR__PURGE_QUEUE, while purged messages that
+   * are in-flight to or from the broker will fail with the error code set to
+   * ERR__PURGE_INFLIGHT.
+   *
+   * @warning Purging messages that are in-flight to or from the broker
+   *          will ignore any sub-sequent acknowledgement for these messages
+   *          received from the broker, effectively making it impossible
+   *          for the application to know if the messages were successfully
+   *          produced or not. This may result in duplicate messages if the
+   *          application retries these messages at a later time.
+   *
+   * @remark This call may block for a short time while background thread
+   *         queues are purged.
+   *
+   * @returns ERR_NO_ERROR on success,
+   *          ERR__INVALID_ARG if the \p purge flags are invalid or unknown,
+   *          ERR__NOT_IMPLEMENTED if called on a non-producer client instance.
+   */
+  virtual ErrorCode purge(int purge_flags) = 0;
+
+  /**
+   * @brief RdKafka::Handle::purge() \p purge_flags
+   */
+  enum {
+    PURGE_QUEUE = 0x1, /**< Purge messages in internal queues */
+
+    PURGE_INFLIGHT = 0x2, /*! Purge messages in-flight to or from the broker.
+                           *  Purging these messages will void any future
+                           *  acknowledgements from the broker, making it
+                           *  impossible for the application to know if these
+                           *  messages were successfully delivered or not.
+                           *  Retrying these messages may lead to duplicates. */
+
+    PURGE_NON_BLOCKING = 0x4 /* Don't wait for background queue
+                              * purging to finish. */
+  };
+
+  /**
+   * @name Transactional API
+   * @{
+   *
+   * Requires Kafka broker version v0.11.0 or later
+   *
+   * See the Transactional API documentation in rdkafka.h for more information.
+   */
+
+  /**
+   * @brief Initialize transactions for the producer instance.
+   *
+   * @param timeout_ms The maximum time to block. On timeout the operation
+   *                   may continue in the background, depending on state,
+   *                   and it is okay to call init_transactions() again.
+   *
+   * @returns an RdKafka::Error object on error, or NULL on success.
+   *          Check whether the returned error object permits retrying
+   *          by calling RdKafka::Error::is_retriable(), or whether a fatal
+   *          error has been raised by calling RdKafka::Error::is_fatal().
+   *
+   * @remark The returned error object (if not NULL) must be deleted.
+   *
+   * See rd_kafka_init_transactions() in rdkafka.h for more information.
+   *
+   */
+  virtual Error *init_transactions(int timeout_ms) = 0;
+
+
+  /**
+   * @brief init_transactions() must have been called successfully
+   *        (once) before this function is called.
+   *
+   * @returns an RdKafka::Error object on error, or NULL on success.
+   *          Check whether a fatal error has been raised by calling
+   *          RdKafka::Error::is_fatal_error().
+   *
+   * @remark The returned error object (if not NULL) must be deleted.
+   *
+   * See rd_kafka_begin_transaction() in rdkafka.h for more information.
+   */
+  virtual Error *begin_transaction() = 0;
+
+  /**
+   * @brief Sends a list of topic partition offsets to the consumer group
+   *        coordinator for \p group_metadata, and marks the offsets as part
+   *        part of the current transaction.
+   *        These offsets will be considered committed only if the transaction
+   *        is committed successfully.
+   *
+   *        The offsets should be the next message your application will
+   *        consume,
+   *        i.e., the last processed message's offset + 1 for each partition.
+   *        Either track the offsets manually during processing or use
+   *        RdKafka::KafkaConsumer::position() (on the consumer) to get the
+   *        current offsets for
+   *        the partitions assigned to the consumer.
+   *
+   *        Use this method at the end of a consume-transform-produce loop prior
+   *        to committing the transaction with commit_transaction().
+   *
+   * @param offsets List of offsets to commit to the consumer group upon
+   *                successful commit of the transaction. Offsets should be
+   *                the next message to consume,
+   *                e.g., last processed message + 1.
+   * @param group_metadata The current consumer group metadata as returned by
+   *                   RdKafka::KafkaConsumer::groupMetadata() on the consumer
+   *                   instance the provided offsets were consumed from.
+   * @param timeout_ms Maximum time allowed to register the
+   *                   offsets on the broker.
+   *
+   * @remark This function must be called on the transactional producer
+   *         instance, not the consumer.
+   *
+   * @remark The consumer must disable auto commits
+   *         (set \c enable.auto.commit to false on the consumer).
+   *
+   * @returns an RdKafka::Error object on error, or NULL on success.
+   *          Check whether the returned error object permits retrying
+   *          by calling RdKafka::Error::is_retriable(), or whether an abortable
+   *          or fatal error has been raised by calling
+   *          RdKafka::Error::txn_requires_abort() or RdKafka::Error::is_fatal()
+   *          respectively.
+   *
+   * @remark The returned error object (if not NULL) must be deleted.
+   *
+   * See rd_kafka_send_offsets_to_transaction() in rdkafka.h for
+   * more information.
+   */
+  virtual Error *send_offsets_to_transaction(
+      const std::vector<TopicPartition *> &offsets,
+      const ConsumerGroupMetadata *group_metadata,
+      int timeout_ms) = 0;
+
+  /**
+   * @brief Commit the current transaction as started with begin_transaction().
+   *
+   *        Any outstanding messages will be flushed (delivered) before actually
+   *        committing the transaction.
+   *
+   * @param timeout_ms The maximum time to block. On timeout the operation
+   *                   may continue in the background, depending on state,
+   *                   and it is okay to call this function again.
+   *                   Pass -1 to use the remaining transaction timeout,
+   *                   this is the recommended use.
+   *
+   * @remark It is strongly recommended to always pass -1 (remaining transaction
+   *         time) as the \p timeout_ms. Using other values risk internal
+   *         state desynchronization in case any of the underlying protocol
+   *         requests fail.
+   *
+   * @returns an RdKafka::Error object on error, or NULL on success.
+   *          Check whether the returned error object permits retrying
+   *          by calling RdKafka::Error::is_retriable(), or whether an abortable
+   *          or fatal error has been raised by calling
+   *          RdKafka::Error::txn_requires_abort() or RdKafka::Error::is_fatal()
+   *          respectively.
+   *
+   * @remark The returned error object (if not NULL) must be deleted.
+   *
+   * See rd_kafka_commit_transaction() in rdkafka.h for more information.
+   */
+  virtual Error *commit_transaction(int timeout_ms) = 0;
+
+  /**
+   * @brief Aborts the ongoing transaction.
+   *
+   *        This function should also be used to recover from non-fatal
+   * abortable transaction errors.
+   *
+   *        Any outstanding messages will be purged and fail with
+   *        RdKafka::ERR__PURGE_INFLIGHT or RdKafka::ERR__PURGE_QUEUE.
+   *        See RdKafka::Producer::purge() for details.
+   *
+   * @param timeout_ms The maximum time to block. On timeout the operation
+   *                   may continue in the background, depending on state,
+   *                   and it is okay to call this function again.
+   *                   Pass -1 to use the remaining transaction timeout,
+   *                   this is the recommended use.
+   *
+   * @remark It is strongly recommended to always pass -1 (remaining transaction
+   *         time) as the \p timeout_ms. Using other values risk internal
+   *         state desynchronization in case any of the underlying protocol
+   *         requests fail.
+   *
+   * @returns an RdKafka::Error object on error, or NULL on success.
+   *          Check whether the returned error object permits retrying
+   *          by calling RdKafka::Error::is_retriable(), or whether a
+   *          fatal error has been raised by calling RdKafka::Error::is_fatal().
+   *
+   * @remark The returned error object (if not NULL) must be deleted.
+   *
+   * See rd_kafka_abort_transaction() in rdkafka.h for more information.
+   */
+  virtual Error *abort_transaction(int timeout_ms) = 0;
+
+  /**@}*/
+};
+
+/**@}*/
+
+
+/**
+ * @name Metadata interface
+ * @{
+ *
+ */
+
+
+/**
+ * @brief Metadata: Broker information
+ */
+class BrokerMetadata {
+ public:
+  /** @returns Broker id */
+  virtual int32_t id() const = 0;
+
+  /** @returns Broker hostname */
+  virtual std::string host() const = 0;
+
+  /** @returns Broker listening port */
+  virtual int port() const = 0;
+
+  virtual ~BrokerMetadata() = 0;
+};
+
+
+
+/**
+ * @brief Metadata: Partition information
+ */
+class PartitionMetadata {
+ public:
+  /** @brief Replicas */
+  typedef std::vector<int32_t> ReplicasVector;
+  /** @brief ISRs (In-Sync-Replicas) */
+  typedef std::vector<int32_t> ISRSVector;
+
+  /** @brief Replicas iterator */
+  typedef ReplicasVector::const_iterator ReplicasIterator;
+  /** @brief ISRs iterator */
+  typedef ISRSVector::const_iterator ISRSIterator;
+
+
+  /** @returns Partition id */
+  virtual int32_t id() const = 0;
+
+  /** @returns Partition error reported by broker */
+  virtual ErrorCode err() const = 0;
+
+  /** @returns Leader broker (id) for partition */
+  virtual int32_t leader() const = 0;
+
+  /** @returns Replica brokers */
+  virtual const std::vector<int32_t> *replicas() const = 0;
+
+  /** @returns In-Sync-Replica brokers
+   *  @warning The broker may return a cached/outdated list of ISRs.
+   */
+  virtual const std::vector<int32_t> *isrs() const = 0;
+
+  virtual ~PartitionMetadata() = 0;
+};
+
+
+
+/**
+ * @brief Metadata: Topic information
+ */
+class TopicMetadata {
+ public:
+  /** @brief Partitions */
+  typedef std::vector<const PartitionMetadata *> PartitionMetadataVector;
+  /** @brief Partitions iterator */
+  typedef PartitionMetadataVector::const_iterator PartitionMetadataIterator;
+
+  /** @returns Topic name */
+  virtual std::string topic() const = 0;
+
+  /** @returns Partition list */
+  virtual const PartitionMetadataVector *partitions() const = 0;
+
+  /** @returns Topic error reported by broker */
+  virtual ErrorCode err() const = 0;
+
+  virtual ~TopicMetadata() = 0;
+};
+
+
+/**
+ * @brief Metadata container
+ */
+class Metadata {
+ public:
+  /** @brief Brokers */
+  typedef std::vector<const BrokerMetadata *> BrokerMetadataVector;
+  /** @brief Topics */
+  typedef std::vector<const TopicMetadata *> TopicMetadataVector;
+
+  /** @brief Brokers iterator */
+  typedef BrokerMetadataVector::const_iterator BrokerMetadataIterator;
+  /** @brief Topics iterator */
+  typedef TopicMetadataVector::const_iterator TopicMetadataIterator;
+
+
+  /**
+   * @brief Broker list
+   * @remark Ownership of the returned pointer is retained by the instance of
+   * Metadata that is called.
+   */
+  virtual const BrokerMetadataVector *brokers() const = 0;
+
+  /**
+   * @brief Topic list
+   * @remark Ownership of the returned pointer is retained by the instance of
+   * Metadata that is called.
+   */
+  virtual const TopicMetadataVector *topics() const = 0;
+
+  /** @brief Broker (id) originating this metadata */
+  virtual int32_t orig_broker_id() const = 0;
+
+  /** @brief Broker (name) originating this metadata */
+  virtual std::string orig_broker_name() const = 0;
+
+  virtual ~Metadata() = 0;
+};
+
+/**@}*/
+
+}  // namespace RdKafka
+
+
+#endif /* _RDKAFKACPP_H_ */
diff --git a/fluent-bit/lib/librdkafka-2.1.0/src-cpp/rdkafkacpp_int.h b/fluent-bit/lib/librdkafka-2.1.0/src-cpp/rdkafkacpp_int.h
new file mode 100644
index 00000000..bc024ebe
--- /dev/null
+++ b/fluent-bit/lib/librdkafka-2.1.0/src-cpp/rdkafkacpp_int.h
@@ -0,0 +1,1628 @@
+/*
+ * librdkafka - Apache Kafka C/C++ library
+ *
+ * Copyright (c) 2014 Magnus Edenhill
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef _RDKAFKACPP_INT_H_
+#define _RDKAFKACPP_INT_H_
+
+#include <string>
+#include <iostream>
+#include <cstring>
+#include <stdlib.h>
+
+#include "rdkafkacpp.h"
+
+extern "C" {
+#include "../src/rdkafka.h"
+}
+
+#ifdef _WIN32
+/* Visual Studio */
+#include "../src/win32_config.h"
+#else
+/* POSIX / UNIX based systems */
+#include "../config.h" /* mklove output */
+#endif
+
+#ifdef _MSC_VER
+typedef int mode_t;
+#pragma warning(disable : 4250)
+#endif
+
+
+namespace RdKafka {
+
+void consume_cb_trampoline(rd_kafka_message_t *msg, void *opaque);
+void log_cb_trampoline(const rd_kafka_t *rk,
+                       int level,
+                       const char *fac,
+                       const char *buf);
+void error_cb_trampoline(rd_kafka_t *rk,
+                         int err,
+                         const char *reason,
+                         void *opaque);
+void throttle_cb_trampoline(rd_kafka_t *rk,
+                            const char *broker_name,
+                            int32_t broker_id,
+                            int throttle_time_ms,
+                            void *opaque);
+int stats_cb_trampoline(rd_kafka_t *rk,
+                        char *json,
+                        size_t json_len,
+                        void *opaque);
+int socket_cb_trampoline(int domain, int type, int protocol, void *opaque);
+int open_cb_trampoline(const char *pathname,
+                       int flags,
+                       mode_t mode,
+                       void *opaque);
+void rebalance_cb_trampoline(rd_kafka_t *rk,
+                             rd_kafka_resp_err_t err,
+                             rd_kafka_topic_partition_list_t *c_partitions,
+                             void *opaque);
+void offset_commit_cb_trampoline0(rd_kafka_t *rk,
+                                  rd_kafka_resp_err_t err,
+                                  rd_kafka_topic_partition_list_t *c_offsets,
+                                  void *opaque);
+void oauthbearer_token_refresh_cb_trampoline(rd_kafka_t *rk,
+                                             const char *oauthbearer_config,
+                                             void *opaque);
+
+int ssl_cert_verify_cb_trampoline(rd_kafka_t *rk,
+                                  const char *broker_name,
+                                  int32_t broker_id,
+                                  int *x509_error,
+                                  int depth,
+                                  const char *buf,
+                                  size_t size,
+                                  char *errstr,
+                                  size_t errstr_size,
+                                  void *opaque);
+
+rd_kafka_topic_partition_list_t *partitions_to_c_parts(
+    const std::vector<TopicPartition *> &partitions);
+
+/**
+ * @brief Update the application provided 'partitions' with info from 'c_parts'
+ */
+void update_partitions_from_c_parts(
+    std::vector<TopicPartition *> &partitions,
+    const rd_kafka_topic_partition_list_t *c_parts);
+
+
+class ErrorImpl : public Error {
+ public:
+  ~ErrorImpl() {
+    rd_kafka_error_destroy(c_error_);
+  }
+
+  ErrorImpl(ErrorCode code, const std::string *errstr) {
+    c_error_ = rd_kafka_error_new(static_cast<rd_kafka_resp_err_t>(code),
+                                  errstr ? "%s" : NULL,
+                                  errstr ? errstr->c_str() : NULL);
+  }
+
+  ErrorImpl(rd_kafka_error_t *c_error) : c_error_(c_error) {
+  }
+
+  static Error *create(ErrorCode code, const std::string *errstr) {
+    return new ErrorImpl(code, errstr);
+  }
+
+  ErrorCode code() const {
+    return static_cast<ErrorCode>(rd_kafka_error_code(c_error_));
+  }
+
+  std::string name() const {
+    return std::string(rd_kafka_error_name(c_error_));
+  }
+
+  std::string str() const {
+    return std::string(rd_kafka_error_string(c_error_));
+  }
+
+  bool is_fatal() const {
+    return !!rd_kafka_error_is_fatal(c_error_);
+  }
+
+  bool is_retriable() const {
+    return !!rd_kafka_error_is_retriable(c_error_);
+  }
+
+  bool txn_requires_abort() const {
+    return !!rd_kafka_error_txn_requires_abort(c_error_);
+  }
+
+  rd_kafka_error_t *c_error_;
+};
+
+
+class EventImpl : public Event {
+ public:
+  ~EventImpl() {
+  }
+
+  EventImpl(Type type,
+            ErrorCode err,
+            Severity severity,
+            const char *fac,
+            const char *str) :
+      type_(type),
+      err_(err),
+      severity_(severity),
+      fac_(fac ? fac : ""),
+      str_(str),
+      id_(0),
+      throttle_time_(0),
+      fatal_(false) {
+  }
+
+  EventImpl(Type type) :
+      type_(type),
+      err_(ERR_NO_ERROR),
+      severity_(EVENT_SEVERITY_EMERG),
+      fac_(""),
+      str_(""),
+      id_(0),
+      throttle_time_(0),
+      fatal_(false) {
+  }
+
+  Type type() const {
+    return type_;
+  }
+  ErrorCode err() const {
+    return err_;
+  }
+  Severity severity() const {
+    return severity_;
+  }
+  std::string fac() const {
+    return fac_;
+  }
+  std::string str() const {
+    return str_;
+  }
+  std::string broker_name() const {
+    if (type_ == EVENT_THROTTLE)
+      return str_;
+    else
+      return std::string("");
+  }
+  int broker_id() const {
+    return id_;
+  }
+  int throttle_time() const {
+    return throttle_time_;
+  }
+
+  bool fatal() const {
+    return fatal_;
+  }
+
+  Type type_;
+  ErrorCode err_;
+  Severity severity_;
+  std::string fac_;
+  std::string str_; /* reused for THROTTLE broker_name */
+  int id_;
+  int throttle_time_;
+  bool fatal_;
+};
+
+class QueueImpl : virtual public Queue {
+ public:
+  QueueImpl(rd_kafka_queue_t *c_rkqu) : queue_(c_rkqu) {
+  }
+  ~QueueImpl() {
+    rd_kafka_queue_destroy(queue_);
+  }
+  static Queue *create(Handle *base);
+  ErrorCode forward(Queue *queue);
+  Message *consume(int timeout_ms);
+  int poll(int timeout_ms);
+  void io_event_enable(int fd, const void *payload, size_t size);
+
+  rd_kafka_queue_t *queue_;
+};
+
+
+
+class HeadersImpl : public Headers {
+ public:
+  HeadersImpl() : headers_(rd_kafka_headers_new(8)) {
+  }
+
+  HeadersImpl(rd_kafka_headers_t *headers) : headers_(headers) {
+  }
+
+  HeadersImpl(const std::vector<Header> &headers) {
+    if (headers.size() > 0) {
+      headers_ = rd_kafka_headers_new(headers.size());
+      from_vector(headers);
+    } else {
+      headers_ = rd_kafka_headers_new(8);
+    }
+  }
+
+  ~HeadersImpl() {
+    if (headers_) {
+      rd_kafka_headers_destroy(headers_);
+    }
+  }
+
+  ErrorCode add(const std::string &key, const char *value) {
+    rd_kafka_resp_err_t err;
+    err = rd_kafka_header_add(headers_, key.c_str(), key.size(), value, -1);
+    return static_cast<RdKafka::ErrorCode>(err);
+  }
+
+  ErrorCode add(const std::string &key, const void *value, size_t value_size) {
+    rd_kafka_resp_err_t err;
+    err = rd_kafka_header_add(headers_, key.c_str(), key.size(), value,
+                              value_size);
+    return static_cast<RdKafka::ErrorCode>(err);
+  }
+
+  ErrorCode add(const std::string &key, const std::string &value) {
+    rd_kafka_resp_err_t err;
+    err = rd_kafka_header_add(headers_, key.c_str(), key.size(), value.c_str(),
+                              value.size());
+    return static_cast<RdKafka::ErrorCode>(err);
+  }
+
+  ErrorCode add(const Header &header) {
+    rd_kafka_resp_err_t err;
+    err =
+        rd_kafka_header_add(headers_, header.key().c_str(), header.key().size(),
+                            header.value(), header.value_size());
+    return static_cast<RdKafka::ErrorCode>(err);
+  }
+
+  ErrorCode remove(const std::string &key) {
+    rd_kafka_resp_err_t err;
+    err = rd_kafka_header_remove(headers_, key.c_str());
+    return static_cast<RdKafka::ErrorCode>(err);
+  }
+
+  std::vector<Headers::Header> get(const std::string &key) const {
+    std::vector<Headers::Header> headers;
+    const void *value;
+    size_t size;
+    rd_kafka_resp_err_t err;
+    for (size_t idx = 0; !(err = rd_kafka_header_get(headers_, idx, key.c_str(),
+                                                     &value, &size));
+         idx++) {
+      headers.push_back(Headers::Header(key, value, size));
+    }
+    return headers;
+  }
+
+  Headers::Header get_last(const std::string &key) const {
+    const void *value;
+    size_t size;
+    rd_kafka_resp_err_t err;
+    err = rd_kafka_header_get_last(headers_, key.c_str(), &value, &size);
+    return Headers::Header(key, value, size,
+                           static_cast<RdKafka::ErrorCode>(err));
+  }
+
+  std::vector<Headers::Header> get_all() const {
+    std::vector<Headers::Header> headers;
+    size_t idx = 0;
+    const char *name;
+    const void *valuep;
+    size_t size;
+    while (!rd_kafka_header_get_all(headers_, idx++, &name, &valuep, &size)) {
+      headers.push_back(Headers::Header(name, valuep, size));
+    }
+    return headers;
+  }
+
+  size_t size() const {
+    return rd_kafka_header_cnt(headers_);
+  }
+
+  /** @brief Reset the C headers pointer to NULL. */
+  void c_headers_destroyed() {
+    headers_ = NULL;
+  }
+
+  /** @returns the underlying C headers, or NULL. */
+  rd_kafka_headers_t *c_ptr() {
+    return headers_;
+  }
+
+
+ private:
+  void from_vector(const std::vector<Header> &headers) {
+    if (headers.size() == 0)
+      return;
+    for (std::vector<Header>::const_iterator it = headers.begin();
+         it != headers.end(); it++)
+      this->add(*it);
+  }
+
+  HeadersImpl(HeadersImpl const &) /*= delete*/;
+  HeadersImpl &operator=(HeadersImpl const &) /*= delete*/;
+
+  rd_kafka_headers_t *headers_;
+};
+
+
+
+class MessageImpl : public Message {
+ public:
+  ~MessageImpl() {
+    if (free_rkmessage_)
+      rd_kafka_message_destroy(const_cast<rd_kafka_message_t *>(rkmessage_));
+    if (key_)
+      delete key_;
+    if (headers_)
+      delete headers_;
+  }
+
+  MessageImpl(rd_kafka_type_t rk_type,
+              RdKafka::Topic *topic,
+              rd_kafka_message_t *rkmessage) :
+      topic_(topic),
+      rkmessage_(rkmessage),
+      free_rkmessage_(true),
+      key_(NULL),
+      headers_(NULL),
+      rk_type_(rk_type) {
+  }
+
+  MessageImpl(rd_kafka_type_t rk_type,
+              RdKafka::Topic *topic,
+              rd_kafka_message_t *rkmessage,
+              bool dofree) :
+      topic_(topic),
+      rkmessage_(rkmessage),
+      free_rkmessage_(dofree),
+      key_(NULL),
+      headers_(NULL),
+      rk_type_(rk_type) {
+  }
+
+  MessageImpl(rd_kafka_type_t rk_type, rd_kafka_message_t *rkmessage) :
+      topic_(NULL),
+      rkmessage_(rkmessage),
+      free_rkmessage_(true),
+      key_(NULL),
+      headers_(NULL),
+      rk_type_(rk_type) {
+    if (rkmessage->rkt) {
+      /* Possibly NULL */
+      topic_ = static_cast<Topic *>(rd_kafka_topic_opaque(rkmessage->rkt));
+    }
+  }
+
+  /* Create errored message */
+  MessageImpl(rd_kafka_type_t rk_type,
+              RdKafka::Topic *topic,
+              RdKafka::ErrorCode err) :
+      topic_(topic),
+      free_rkmessage_(false),
+      key_(NULL),
+      headers_(NULL),
+      rk_type_(rk_type) {
+    rkmessage_ = &rkmessage_err_;
+    memset(&rkmessage_err_, 0, sizeof(rkmessage_err_));
+    rkmessage_err_.err = static_cast<rd_kafka_resp_err_t>(err);
+  }
+
+  std::string errstr() const {
+    const char *es;
+    /* message_errstr() is only available for the consumer. */
+    if (rk_type_ == RD_KAFKA_CONSUMER)
+      es = rd_kafka_message_errstr(rkmessage_);
+    else
+      es = rd_kafka_err2str(rkmessage_->err);
+
+    return std::string(es ? es : "");
+  }
+
+  ErrorCode err() const {
+    return static_cast<RdKafka::ErrorCode>(rkmessage_->err);
+  }
+
+  Topic *topic() const {
+    return topic_;
+  }
+  std::string topic_name() const {
+    if (rkmessage_->rkt)
+      return rd_kafka_topic_name(rkmessage_->rkt);
+    else
+      return "";
+  }
+  int32_t partition() const {
+    return rkmessage_->partition;
+  }
+  void *payload() const {
+    return rkmessage_->payload;
+  }
+  size_t len() const {
+    return rkmessage_->len;
+  }
+  const std::string *key() const {
+    if (key_) {
+      return key_;
+    } else if (rkmessage_->key) {
+      key_ = new std::string(static_cast<char const *>(rkmessage_->key),
+                             rkmessage_->key_len);
+      return key_;
+    }
+    return NULL;
+  }
+  const void *key_pointer() const {
+    return rkmessage_->key;
+  }
+  size_t key_len() const {
+    return rkmessage_->key_len;
+  }
+
+  int64_t offset() const {
+    return rkmessage_->offset;
+  }
+
+  MessageTimestamp timestamp() const {
+    MessageTimestamp ts;
+    rd_kafka_timestamp_type_t tstype;
+    ts.timestamp = rd_kafka_message_timestamp(rkmessage_, &tstype);
+    ts.type      = static_cast<MessageTimestamp::MessageTimestampType>(tstype);
+    return ts;
+  }
+
+  void *msg_opaque() const {
+    return rkmessage_->_private;
+  }
+
+  int64_t latency() const {
+    return rd_kafka_message_latency(rkmessage_);
+  }
+
+  struct rd_kafka_message_s *c_ptr() {
+    return rkmessage_;
+  }
+
+  Status status() const {
+    return static_cast<Status>(rd_kafka_message_status(rkmessage_));
+  }
+
+  Headers *headers() {
+    ErrorCode err;
+    return headers(&err);
+  }
+
+  Headers *headers(ErrorCode *err) {
+    *err = ERR_NO_ERROR;
+
+    if (!headers_) {
+      rd_kafka_headers_t *c_hdrs;
+      rd_kafka_resp_err_t c_err;
+
+      if ((c_err = rd_kafka_message_detach_headers(rkmessage_, &c_hdrs))) {
+        *err = static_cast<RdKafka::ErrorCode>(c_err);
+        return NULL;
+      }
+
+      headers_ = new HeadersImpl(c_hdrs);
+    }
+
+    return headers_;
+  }
+
+  int32_t broker_id() const {
+    return rd_kafka_message_broker_id(rkmessage_);
+  }
+
+  int32_t leader_epoch() const {
+    return rd_kafka_message_leader_epoch(rkmessage_);
+  }
+
+
+  Error *offset_store() {
+    rd_kafka_error_t *c_error;
+
+    c_error = rd_kafka_offset_store_message(rkmessage_);
+
+    if (c_error)
+      return new ErrorImpl(c_error);
+    else
+      return NULL;
+  }
+
+  RdKafka::Topic *topic_;
+  rd_kafka_message_t *rkmessage_;
+  bool free_rkmessage_;
+  /* For error signalling by the C++ layer the .._err_ message is
+   * used as a place holder and rkmessage_ is set to point to it. */
+  rd_kafka_message_t rkmessage_err_;
+  mutable std::string *key_; /* mutable because it's a cached value */
+
+ private:
+  /* "delete" copy ctor + copy assignment, for safety of key_ */
+  MessageImpl(MessageImpl const &) /*= delete*/;
+  MessageImpl &operator=(MessageImpl const &) /*= delete*/;
+
+  RdKafka::Headers *headers_;
+  const rd_kafka_type_t rk_type_; /**< Client type */
+};
+
+
+class ConfImpl : public Conf {
+ public:
+  ConfImpl(ConfType conf_type) :
+      consume_cb_(NULL),
+      dr_cb_(NULL),
+      event_cb_(NULL),
+      socket_cb_(NULL),
+      open_cb_(NULL),
+      partitioner_cb_(NULL),
+      partitioner_kp_cb_(NULL),
+      rebalance_cb_(NULL),
+      offset_commit_cb_(NULL),
+      oauthbearer_token_refresh_cb_(NULL),
+      ssl_cert_verify_cb_(NULL),
+      conf_type_(conf_type),
+      rk_conf_(NULL),
+      rkt_conf_(NULL) {
+  }
+  ~ConfImpl() {
+    if (rk_conf_)
+      rd_kafka_conf_destroy(rk_conf_);
+    else if (rkt_conf_)
+      rd_kafka_topic_conf_destroy(rkt_conf_);
+  }
+
+  Conf::ConfResult set(const std::string &name,
+                       const std::string &value,
+                       std::string &errstr);
+
+  Conf::ConfResult set(const std::string &name,
+                       DeliveryReportCb *dr_cb,
+                       std::string &errstr) {
+    if (name != "dr_cb") {
+      errstr = "Invalid value type, expected RdKafka::DeliveryReportCb";
+      return Conf::CONF_INVALID;
+    }
+
+    if (!rk_conf_) {
+      errstr = "Requires RdKafka::Conf::CONF_GLOBAL object";
+      return Conf::CONF_INVALID;
+    }
+
+    dr_cb_ = dr_cb;
+    return Conf::CONF_OK;
+  }
+
+  Conf::ConfResult set(const std::string &name,
+                       OAuthBearerTokenRefreshCb *oauthbearer_token_refresh_cb,
+                       std::string &errstr) {
+    if (name != "oauthbearer_token_refresh_cb") {
+      errstr =
+          "Invalid value type, expected RdKafka::OAuthBearerTokenRefreshCb";
+      return Conf::CONF_INVALID;
+    }
+
+    if (!rk_conf_) {
+      errstr = "Requires RdKafka::Conf::CONF_GLOBAL object";
+      return Conf::CONF_INVALID;
+    }
+
+    oauthbearer_token_refresh_cb_ = oauthbearer_token_refresh_cb;
+    return Conf::CONF_OK;
+  }
+
+  Conf::ConfResult set(const std::string &name,
+                       EventCb *event_cb,
+                       std::string &errstr) {
+    if (name != "event_cb") {
+      errstr = "Invalid value type, expected RdKafka::EventCb";
+      return Conf::CONF_INVALID;
+    }
+
+    if (!rk_conf_) {
+      errstr = "Requires RdKafka::Conf::CONF_GLOBAL object";
+      return Conf::CONF_INVALID;
+    }
+
+    event_cb_ = event_cb;
+    return Conf::CONF_OK;
+  }
+
+  Conf::ConfResult set(const std::string &name,
+                       const Conf *topic_conf,
+                       std::string &errstr) {
+    const ConfImpl *tconf_impl =
+        dynamic_cast<const RdKafka::ConfImpl *>(topic_conf);
+    if (name != "default_topic_conf" || !tconf_impl->rkt_conf_) {
+      errstr = "Invalid value type, expected RdKafka::Conf";
+      return Conf::CONF_INVALID;
+    }
+
+    if (!rk_conf_) {
+      errstr = "Requires RdKafka::Conf::CONF_GLOBAL object";
+      return Conf::CONF_INVALID;
+    }
+
+    rd_kafka_conf_set_default_topic_conf(
+        rk_conf_, rd_kafka_topic_conf_dup(tconf_impl->rkt_conf_));
+
+    return Conf::CONF_OK;
+  }
+
+  Conf::ConfResult set(const std::string &name,
+                       PartitionerCb *partitioner_cb,
+                       std::string &errstr) {
+    if (name != "partitioner_cb") {
+      errstr = "Invalid value type, expected RdKafka::PartitionerCb";
+      return Conf::CONF_INVALID;
+    }
+
+    if (!rkt_conf_) {
+      errstr = "Requires RdKafka::Conf::CONF_TOPIC object";
+      return Conf::CONF_INVALID;
+    }
+
+    partitioner_cb_ = partitioner_cb;
+    return Conf::CONF_OK;
+  }
+
+  Conf::ConfResult set(const std::string &name,
+                       PartitionerKeyPointerCb *partitioner_kp_cb,
+                       std::string &errstr) {
+    if (name != "partitioner_key_pointer_cb") {
+      errstr = "Invalid value type, expected RdKafka::PartitionerKeyPointerCb";
+      return Conf::CONF_INVALID;
+    }
+
+    if (!rkt_conf_) {
+      errstr = "Requires RdKafka::Conf::CONF_TOPIC object";
+      return Conf::CONF_INVALID;
+    }
+
+    partitioner_kp_cb_ = partitioner_kp_cb;
+    return Conf::CONF_OK;
+  }
+
+  Conf::ConfResult set(const std::string &name,
+                       SocketCb *socket_cb,
+                       std::string &errstr) {
+    if (name != "socket_cb") {
+      errstr = "Invalid value type, expected RdKafka::SocketCb";
+      return Conf::CONF_INVALID;
+    }
+
+    if (!rk_conf_) {
+      errstr = "Requires RdKafka::Conf::CONF_GLOBAL object";
+      return Conf::CONF_INVALID;
+    }
+
+    socket_cb_ = socket_cb;
+    return Conf::CONF_OK;
+  }
+
+
+  Conf::ConfResult set(const std::string &name,
+                       OpenCb *open_cb,
+                       std::string &errstr) {
+    if (name != "open_cb") {
+      errstr = "Invalid value type, expected RdKafka::OpenCb";
+      return Conf::CONF_INVALID;
+    }
+
+    if (!rk_conf_) {
+      errstr = "Requires RdKafka::Conf::CONF_GLOBAL object";
+      return Conf::CONF_INVALID;
+    }
+
+    open_cb_ = open_cb;
+    return Conf::CONF_OK;
+  }
+
+
+
+  Conf::ConfResult set(const std::string &name,
+                       RebalanceCb *rebalance_cb,
+                       std::string &errstr) {
+    if (name != "rebalance_cb") {
+      errstr = "Invalid value type, expected RdKafka::RebalanceCb";
+      return Conf::CONF_INVALID;
+    }
+
+    if (!rk_conf_) {
+      errstr = "Requires RdKafka::Conf::CONF_GLOBAL object";
+      return Conf::CONF_INVALID;
+    }
+
+    rebalance_cb_ = rebalance_cb;
+    return Conf::CONF_OK;
+  }
+
+
+  Conf::ConfResult set(const std::string &name,
+                       OffsetCommitCb *offset_commit_cb,
+                       std::string &errstr) {
+    if (name != "offset_commit_cb") {
+      errstr = "Invalid value type, expected RdKafka::OffsetCommitCb";
+      return Conf::CONF_INVALID;
+    }
+
+    if (!rk_conf_) {
+      errstr = "Requires RdKafka::Conf::CONF_GLOBAL object";
+      return Conf::CONF_INVALID;
+    }
+
+    offset_commit_cb_ = offset_commit_cb;
+    return Conf::CONF_OK;
+  }
+
+
+  Conf::ConfResult set(const std::string &name,
+                       SslCertificateVerifyCb *ssl_cert_verify_cb,
+                       std::string &errstr) {
+    if (name != "ssl_cert_verify_cb") {
+      errstr = "Invalid value type, expected RdKafka::SslCertificateVerifyCb";
+      return Conf::CONF_INVALID;
+    }
+
+    if (!rk_conf_) {
+      errstr = "Requires RdKafka::Conf::CONF_GLOBAL object";
+      return Conf::CONF_INVALID;
+    }
+
+    ssl_cert_verify_cb_ = ssl_cert_verify_cb;
+    return Conf::CONF_OK;
+  }
+
+  Conf::ConfResult set_engine_callback_data(void *value, std::string &errstr) {
+    if (!rk_conf_) {
+      errstr = "Requires RdKafka::Conf::CONF_GLOBAL object";
+      return Conf::CONF_INVALID;
+    }
+
+    rd_kafka_conf_set_engine_callback_data(rk_conf_, value);
+    return Conf::CONF_OK;
+  }
+
+
+  Conf::ConfResult set_ssl_cert(RdKafka::CertificateType cert_type,
+                                RdKafka::CertificateEncoding cert_enc,
+                                const void *buffer,
+                                size_t size,
+                                std::string &errstr) {
+    rd_kafka_conf_res_t res;
+    char errbuf[512];
+
+    if (!rk_conf_) {
+      errstr = "Requires RdKafka::Conf::CONF_GLOBAL object";
+      return Conf::CONF_INVALID;
+    }
+
+    res = rd_kafka_conf_set_ssl_cert(
+        rk_conf_, static_cast<rd_kafka_cert_type_t>(cert_type),
+        static_cast<rd_kafka_cert_enc_t>(cert_enc), buffer, size, errbuf,
+        sizeof(errbuf));
+
+    if (res != RD_KAFKA_CONF_OK)
+      errstr = errbuf;
+
+    return static_cast<Conf::ConfResult>(res);
+  }
+
+  Conf::ConfResult enable_sasl_queue(bool enable, std::string &errstr) {
+    if (!rk_conf_) {
+      errstr = "Requires RdKafka::Conf::CONF_GLOBAL object";
+      return Conf::CONF_INVALID;
+    }
+
+    rd_kafka_conf_enable_sasl_queue(rk_conf_, enable ? 1 : 0);
+
+    return Conf::CONF_OK;
+  }
+
+
+  Conf::ConfResult get(const std::string &name, std::string &value) const {
+    if (name.compare("dr_cb") == 0 || name.compare("event_cb") == 0 ||
+        name.compare("partitioner_cb") == 0 ||
+        name.compare("partitioner_key_pointer_cb") == 0 ||
+        name.compare("socket_cb") == 0 || name.compare("open_cb") == 0 ||
+        name.compare("rebalance_cb") == 0 ||
+        name.compare("offset_commit_cb") == 0 ||
+        name.compare("oauthbearer_token_refresh_cb") == 0 ||
+        name.compare("ssl_cert_verify_cb") == 0 ||
+        name.compare("set_engine_callback_data") == 0 ||
+        name.compare("enable_sasl_queue") == 0) {
+      return Conf::CONF_INVALID;
+    }
+    rd_kafka_conf_res_t res = RD_KAFKA_CONF_INVALID;
+
+    /* Get size of property */
+    size_t size;
+    if (rk_conf_)
+      res = rd_kafka_conf_get(rk_conf_, name.c_str(), NULL, &size);
+    else if (rkt_conf_)
+      res = rd_kafka_topic_conf_get(rkt_conf_, name.c_str(), NULL, &size);
+    if (res != RD_KAFKA_CONF_OK)
+      return static_cast<Conf::ConfResult>(res);
+
+    char *tmpValue = new char[size];
+
+    if (rk_conf_)
+      res = rd_kafka_conf_get(rk_conf_, name.c_str(), tmpValue, &size);
+    else if (rkt_conf_)
+      res = rd_kafka_topic_conf_get(rkt_conf_, name.c_str(), tmpValue, &size);
+
+    if (res == RD_KAFKA_CONF_OK)
+      value.assign(tmpValue);
+    delete[] tmpValue;
+
+    return static_cast<Conf::ConfResult>(res);
+  }
+
+  Conf::ConfResult get(DeliveryReportCb *&dr_cb) const {
+    if (!rk_conf_)
+      return Conf::CONF_INVALID;
+    dr_cb = this->dr_cb_;
+    return Conf::CONF_OK;
+  }
+
+  Conf::ConfResult get(
+      OAuthBearerTokenRefreshCb *&oauthbearer_token_refresh_cb) const {
+    if (!rk_conf_)
+      return Conf::CONF_INVALID;
+    oauthbearer_token_refresh_cb = this->oauthbearer_token_refresh_cb_;
+    return Conf::CONF_OK;
+  }
+
+  Conf::ConfResult get(EventCb *&event_cb) const {
+    if (!rk_conf_)
+      return Conf::CONF_INVALID;
+    event_cb = this->event_cb_;
+    return Conf::CONF_OK;
+  }
+
+  Conf::ConfResult get(PartitionerCb *&partitioner_cb) const {
+    if (!rkt_conf_)
+      return Conf::CONF_INVALID;
+    partitioner_cb = this->partitioner_cb_;
+    return Conf::CONF_OK;
+  }
+
+  Conf::ConfResult get(PartitionerKeyPointerCb *&partitioner_kp_cb) const {
+    if (!rkt_conf_)
+      return Conf::CONF_INVALID;
+    partitioner_kp_cb = this->partitioner_kp_cb_;
+    return Conf::CONF_OK;
+  }
+
+  Conf::ConfResult get(SocketCb *&socket_cb) const {
+    if (!rk_conf_)
+      return Conf::CONF_INVALID;
+    socket_cb = this->socket_cb_;
+    return Conf::CONF_OK;
+  }
+
+  Conf::ConfResult get(OpenCb *&open_cb) const {
+    if (!rk_conf_)
+      return Conf::CONF_INVALID;
+    open_cb = this->open_cb_;
+    return Conf::CONF_OK;
+  }
+
+  Conf::ConfResult get(RebalanceCb *&rebalance_cb) const {
+    if (!rk_conf_)
+      return Conf::CONF_INVALID;
+    rebalance_cb = this->rebalance_cb_;
+    return Conf::CONF_OK;
+  }
+
+  Conf::ConfResult get(OffsetCommitCb *&offset_commit_cb) const {
+    if (!rk_conf_)
+      return Conf::CONF_INVALID;
+    offset_commit_cb = this->offset_commit_cb_;
+    return Conf::CONF_OK;
+  }
+
+  Conf::ConfResult get(SslCertificateVerifyCb *&ssl_cert_verify_cb) const {
+    if (!rk_conf_)
+      return Conf::CONF_INVALID;
+    ssl_cert_verify_cb = this->ssl_cert_verify_cb_;
+    return Conf::CONF_OK;
+  }
+
+  std::list<std::string> *dump();
+
+
+  Conf::ConfResult set(const std::string &name,
+                       ConsumeCb *consume_cb,
+                       std::string &errstr) {
+    if (name != "consume_cb") {
+      errstr = "Invalid value type, expected RdKafka::ConsumeCb";
+      return Conf::CONF_INVALID;
+    }
+
+    if (!rk_conf_) {
+      errstr = "Requires RdKafka::Conf::CONF_GLOBAL object";
+      return Conf::CONF_INVALID;
+    }
+
+    consume_cb_ = consume_cb;
+    return Conf::CONF_OK;
+  }
+
+  struct rd_kafka_conf_s *c_ptr_global() {
+    if (conf_type_ == CONF_GLOBAL)
+      return rk_conf_;
+    else
+      return NULL;
+  }
+
+  struct rd_kafka_topic_conf_s *c_ptr_topic() {
+    if (conf_type_ == CONF_TOPIC)
+      return rkt_conf_;
+    else
+      return NULL;
+  }
+
+  ConsumeCb *consume_cb_;
+  DeliveryReportCb *dr_cb_;
+  EventCb *event_cb_;
+  SocketCb *socket_cb_;
+  OpenCb *open_cb_;
+  PartitionerCb *partitioner_cb_;
+  PartitionerKeyPointerCb *partitioner_kp_cb_;
+  RebalanceCb *rebalance_cb_;
+  OffsetCommitCb *offset_commit_cb_;
+  OAuthBearerTokenRefreshCb *oauthbearer_token_refresh_cb_;
+  SslCertificateVerifyCb *ssl_cert_verify_cb_;
+  ConfType conf_type_;
+  rd_kafka_conf_t *rk_conf_;
+  rd_kafka_topic_conf_t *rkt_conf_;
+};
+
+
+class HandleImpl : virtual public Handle {
+ public:
+  ~HandleImpl() {
+  }
+  HandleImpl() {
+  }
+  std::string name() const {
+    return std::string(rd_kafka_name(rk_));
+  }
+  std::string memberid() const {
+    char *str            = rd_kafka_memberid(rk_);
+    std::string memberid = str ? str : "";
+    if (str)
+      rd_kafka_mem_free(rk_, str);
+    return memberid;
+  }
+  int poll(int timeout_ms) {
+    return rd_kafka_poll(rk_, timeout_ms);
+  }
+  int outq_len() {
+    return rd_kafka_outq_len(rk_);
+  }
+
+  void set_common_config(const RdKafka::ConfImpl *confimpl);
+
+  RdKafka::ErrorCode metadata(bool all_topics,
+                              const Topic *only_rkt,
+                              Metadata **metadatap,
+                              int timeout_ms);
+
+  ErrorCode pause(std::vector<TopicPartition *> &partitions);
+  ErrorCode resume(std::vector<TopicPartition *> &partitions);
+
+  ErrorCode query_watermark_offsets(const std::string &topic,
+                                    int32_t partition,
+                                    int64_t *low,
+                                    int64_t *high,
+                                    int timeout_ms) {
+    return static_cast<RdKafka::ErrorCode>(rd_kafka_query_watermark_offsets(
+        rk_, topic.c_str(), partition, low, high, timeout_ms));
+  }
+
+  ErrorCode get_watermark_offsets(const std::string &topic,
+                                  int32_t partition,
+                                  int64_t *low,
+                                  int64_t *high) {
+    return static_cast<RdKafka::ErrorCode>(rd_kafka_get_watermark_offsets(
+        rk_, topic.c_str(), partition, low, high));
+  }
+
+  Queue *get_partition_queue(const TopicPartition *partition);
+
+  Queue *get_sasl_queue() {
+    rd_kafka_queue_t *rkqu;
+    rkqu = rd_kafka_queue_get_sasl(rk_);
+
+    if (rkqu == NULL)
+      return NULL;
+
+    return new QueueImpl(rkqu);
+  }
+
+  Queue *get_background_queue() {
+    rd_kafka_queue_t *rkqu;
+    rkqu = rd_kafka_queue_get_background(rk_);
+
+    if (rkqu == NULL)
+      return NULL;
+
+    return new QueueImpl(rkqu);
+  }
+
+
+  ErrorCode offsetsForTimes(std::vector<TopicPartition *> &offsets,
+                            int timeout_ms) {
+    rd_kafka_topic_partition_list_t *c_offsets = partitions_to_c_parts(offsets);
+    ErrorCode err                              = static_cast<ErrorCode>(
+        rd_kafka_offsets_for_times(rk_, c_offsets, timeout_ms));
+    update_partitions_from_c_parts(offsets, c_offsets);
+    rd_kafka_topic_partition_list_destroy(c_offsets);
+    return err;
+  }
+
+  ErrorCode set_log_queue(Queue *queue);
+
+  void yield() {
+    rd_kafka_yield(rk_);
+  }
+
+  std::string clusterid(int timeout_ms) {
+    char *str             = rd_kafka_clusterid(rk_, timeout_ms);
+    std::string clusterid = str ? str : "";
+    if (str)
+      rd_kafka_mem_free(rk_, str);
+    return clusterid;
+  }
+
+  struct rd_kafka_s *c_ptr() {
+    return rk_;
+  }
+
+  int32_t controllerid(int timeout_ms) {
+    return rd_kafka_controllerid(rk_, timeout_ms);
+  }
+
+  ErrorCode fatal_error(std::string &errstr) const {
+    char errbuf[512];
+    RdKafka::ErrorCode err = static_cast<RdKafka::ErrorCode>(
+        rd_kafka_fatal_error(rk_, errbuf, sizeof(errbuf)));
+    if (err)
+      errstr = errbuf;
+    return err;
+  }
+
+  ErrorCode oauthbearer_set_token(const std::string &token_value,
+                                  int64_t md_lifetime_ms,
+                                  const std::string &md_principal_name,
+                                  const std::list<std::string> &extensions,
+                                  std::string &errstr) {
+    char errbuf[512];
+    ErrorCode err;
+    const char **extensions_copy = new const char *[extensions.size()];
+    int elem                     = 0;
+
+    for (std::list<std::string>::const_iterator it = extensions.begin();
+         it != extensions.end(); it++)
+      extensions_copy[elem++] = it->c_str();
+    err = static_cast<ErrorCode>(rd_kafka_oauthbearer_set_token(
+        rk_, token_value.c_str(), md_lifetime_ms, md_principal_name.c_str(),
+        extensions_copy, extensions.size(), errbuf, sizeof(errbuf)));
+    delete[] extensions_copy;
+
+    if (err != ERR_NO_ERROR)
+      errstr = errbuf;
+
+    return err;
+  }
+
+  ErrorCode oauthbearer_set_token_failure(const std::string &errstr) {
+    return static_cast<ErrorCode>(
+        rd_kafka_oauthbearer_set_token_failure(rk_, errstr.c_str()));
+  }
+
+  Error *sasl_background_callbacks_enable() {
+    rd_kafka_error_t *c_error = rd_kafka_sasl_background_callbacks_enable(rk_);
+
+    if (c_error)
+      return new ErrorImpl(c_error);
+
+    return NULL;
+  }
+
+  Error *sasl_set_credentials(const std::string &username,
+                              const std::string &password) {
+    rd_kafka_error_t *c_error =
+        rd_kafka_sasl_set_credentials(rk_, username.c_str(), password.c_str());
+
+    if (c_error)
+      return new ErrorImpl(c_error);
+
+    return NULL;
+  };
+
+  void *mem_malloc(size_t size) {
+    return rd_kafka_mem_malloc(rk_, size);
+  }
+
+  void mem_free(void *ptr) {
+    rd_kafka_mem_free(rk_, ptr);
+  }
+
+  rd_kafka_t *rk_;
+  /* All Producer and Consumer callbacks must reside in HandleImpl and
+   * the opaque provided to rdkafka must be a pointer to HandleImpl, since
+   * ProducerImpl and ConsumerImpl classes cannot be safely directly cast to
+   * HandleImpl due to the skewed diamond inheritance. */
+  ConsumeCb *consume_cb_;
+  EventCb *event_cb_;
+  SocketCb *socket_cb_;
+  OpenCb *open_cb_;
+  DeliveryReportCb *dr_cb_;
+  PartitionerCb *partitioner_cb_;
+  PartitionerKeyPointerCb *partitioner_kp_cb_;
+  RebalanceCb *rebalance_cb_;
+  OffsetCommitCb *offset_commit_cb_;
+  OAuthBearerTokenRefreshCb *oauthbearer_token_refresh_cb_;
+  SslCertificateVerifyCb *ssl_cert_verify_cb_;
+};
+
+
+class TopicImpl : public Topic {
+ public:
+  ~TopicImpl() {
+    rd_kafka_topic_destroy(rkt_);
+  }
+
+  std::string name() const {
+    return rd_kafka_topic_name(rkt_);
+  }
+
+  bool partition_available(int32_t partition) const {
+    return !!rd_kafka_topic_partition_available(rkt_, partition);
+  }
+
+  ErrorCode offset_store(int32_t partition, int64_t offset) {
+    return static_cast<RdKafka::ErrorCode>(
+        rd_kafka_offset_store(rkt_, partition, offset));
+  }
+
+  static Topic *create(Handle &base, const std::string &topic, Conf *conf);
+
+  struct rd_kafka_topic_s *c_ptr() {
+    return rkt_;
+  }
+
+  rd_kafka_topic_t *rkt_;
+  PartitionerCb *partitioner_cb_;
+  PartitionerKeyPointerCb *partitioner_kp_cb_;
+};
+
+
+/**
+ * Topic and Partition
+ */
+class TopicPartitionImpl : public TopicPartition {
+ public:
+  ~TopicPartitionImpl() {
+  }
+
+  static TopicPartition *create(const std::string &topic, int partition);
+
+  TopicPartitionImpl(const std::string &topic, int partition) :
+      topic_(topic),
+      partition_(partition),
+      offset_(RdKafka::Topic::OFFSET_INVALID),
+      err_(ERR_NO_ERROR),
+      leader_epoch_(-1) {
+  }
+
+  TopicPartitionImpl(const std::string &topic, int partition, int64_t offset) :
+      topic_(topic),
+      partition_(partition),
+      offset_(offset),
+      err_(ERR_NO_ERROR),
+      leader_epoch_(-1) {
+  }
+
+  TopicPartitionImpl(const rd_kafka_topic_partition_t *c_part) {
+    topic_        = std::string(c_part->topic);
+    partition_    = c_part->partition;
+    offset_       = c_part->offset;
+    err_          = static_cast<ErrorCode>(c_part->err);
+    leader_epoch_ = rd_kafka_topic_partition_get_leader_epoch(c_part);
+    // FIXME: metadata
+  }
+
+  static void destroy(std::vector<TopicPartition *> &partitions);
+
+  int partition() const {
+    return partition_;
+  }
+  const std::string &topic() const {
+    return topic_;
+  }
+
+  int64_t offset() const {
+    return offset_;
+  }
+
+  ErrorCode err() const {
+    return err_;
+  }
+
+  void set_offset(int64_t offset) {
+    offset_ = offset;
+  }
+
+  int32_t get_leader_epoch() {
+    return leader_epoch_;
+  }
+
+  void set_leader_epoch(int32_t leader_epoch) {
+    leader_epoch_ = leader_epoch_;
+  }
+
+  std::ostream &operator<<(std::ostream &ostrm) const {
+    return ostrm << topic_ << " [" << partition_ << "]";
+  }
+
+  std::string topic_;
+  int partition_;
+  int64_t offset_;
+  ErrorCode err_;
+  int32_t leader_epoch_;
+};
+
+
+/**
+ * @class ConsumerGroupMetadata wraps the
+ *        C rd_kafka_consumer_group_metadata_t object.
+ */
+class ConsumerGroupMetadataImpl : public ConsumerGroupMetadata {
+ public:
+  ~ConsumerGroupMetadataImpl() {
+    rd_kafka_consumer_group_metadata_destroy(cgmetadata_);
+  }
+
+  ConsumerGroupMetadataImpl(rd_kafka_consumer_group_metadata_t *cgmetadata) :
+      cgmetadata_(cgmetadata) {
+  }
+
+  rd_kafka_consumer_group_metadata_t *cgmetadata_;
+};
+
+
+class KafkaConsumerImpl : virtual public KafkaConsumer,
+                          virtual public HandleImpl {
+ public:
+  ~KafkaConsumerImpl() {
+    if (rk_)
+      rd_kafka_destroy_flags(rk_, RD_KAFKA_DESTROY_F_NO_CONSUMER_CLOSE);
+  }
+
+  static KafkaConsumer *create(Conf *conf, std::string &errstr);
+
+  ErrorCode assignment(std::vector<TopicPartition *> &partitions);
+  bool assignment_lost();
+  std::string rebalance_protocol() {
+    const char *str = rd_kafka_rebalance_protocol(rk_);
+    return std::string(str ? str : "");
+  }
+  ErrorCode subscription(std::vector<std::string> &topics);
+  ErrorCode subscribe(const std::vector<std::string> &topics);
+  ErrorCode unsubscribe();
+  ErrorCode assign(const std::vector<TopicPartition *> &partitions);
+  ErrorCode unassign();
+  Error *incremental_assign(const std::vector<TopicPartition *> &partitions);
+  Error *incremental_unassign(const std::vector<TopicPartition *> &partitions);
+
+  Message *consume(int timeout_ms);
+  ErrorCode commitSync() {
+    return static_cast<ErrorCode>(rd_kafka_commit(rk_, NULL, 0 /*sync*/));
+  }
+  ErrorCode commitAsync() {
+    return static_cast<ErrorCode>(rd_kafka_commit(rk_, NULL, 1 /*async*/));
+  }
+  ErrorCode commitSync(Message *message) {
+    MessageImpl *msgimpl = dynamic_cast<MessageImpl *>(message);
+    return static_cast<ErrorCode>(
+        rd_kafka_commit_message(rk_, msgimpl->rkmessage_, 0 /*sync*/));
+  }
+  ErrorCode commitAsync(Message *message) {
+    MessageImpl *msgimpl = dynamic_cast<MessageImpl *>(message);
+    return static_cast<ErrorCode>(
+        rd_kafka_commit_message(rk_, msgimpl->rkmessage_, 1 /*async*/));
+  }
+
+  ErrorCode commitSync(std::vector<TopicPartition *> &offsets) {
+    rd_kafka_topic_partition_list_t *c_parts = partitions_to_c_parts(offsets);
+    rd_kafka_resp_err_t err                  = rd_kafka_commit(rk_, c_parts, 0);
+    if (!err)
+      update_partitions_from_c_parts(offsets, c_parts);
+    rd_kafka_topic_partition_list_destroy(c_parts);
+    return static_cast<ErrorCode>(err);
+  }
+
+  ErrorCode commitAsync(const std::vector<TopicPartition *> &offsets) {
+    rd_kafka_topic_partition_list_t *c_parts = partitions_to_c_parts(offsets);
+    rd_kafka_resp_err_t err                  = rd_kafka_commit(rk_, c_parts, 1);
+    rd_kafka_topic_partition_list_destroy(c_parts);
+    return static_cast<ErrorCode>(err);
+  }
+
+  ErrorCode commitSync(OffsetCommitCb *offset_commit_cb) {
+    return static_cast<ErrorCode>(rd_kafka_commit_queue(
+        rk_, NULL, NULL, RdKafka::offset_commit_cb_trampoline0,
+        offset_commit_cb));
+  }
+
+  ErrorCode commitSync(std::vector<TopicPartition *> &offsets,
+                       OffsetCommitCb *offset_commit_cb) {
+    rd_kafka_topic_partition_list_t *c_parts = partitions_to_c_parts(offsets);
+    rd_kafka_resp_err_t err                  = rd_kafka_commit_queue(
+        rk_, c_parts, NULL, RdKafka::offset_commit_cb_trampoline0,
+        offset_commit_cb);
+    rd_kafka_topic_partition_list_destroy(c_parts);
+    return static_cast<ErrorCode>(err);
+  }
+
+  ErrorCode committed(std::vector<TopicPartition *> &partitions,
+                      int timeout_ms);
+  ErrorCode position(std::vector<TopicPartition *> &partitions);
+
+  ConsumerGroupMetadata *groupMetadata() {
+    rd_kafka_consumer_group_metadata_t *cgmetadata;
+
+    cgmetadata = rd_kafka_consumer_group_metadata(rk_);
+    if (!cgmetadata)
+      return NULL;
+
+    return new ConsumerGroupMetadataImpl(cgmetadata);
+  }
+
+  ErrorCode close();
+
+  Error *close(Queue *queue);
+
+  bool closed() {
+    return rd_kafka_consumer_closed(rk_) ? true : false;
+  }
+
+  ErrorCode seek(const TopicPartition &partition, int timeout_ms);
+
+  ErrorCode offsets_store(std::vector<TopicPartition *> &offsets) {
+    rd_kafka_topic_partition_list_t *c_parts = partitions_to_c_parts(offsets);
+    rd_kafka_resp_err_t err = rd_kafka_offsets_store(rk_, c_parts);
+    update_partitions_from_c_parts(offsets, c_parts);
+    rd_kafka_topic_partition_list_destroy(c_parts);
+    return static_cast<ErrorCode>(err);
+  }
+};
+
+
+class MetadataImpl : public Metadata {
+ public:
+  MetadataImpl(const rd_kafka_metadata_t *metadata);
+  ~MetadataImpl();
+
+  const std::vector<const BrokerMetadata *> *brokers() const {
+    return &brokers_;
+  }
+
+  const std::vector<const TopicMetadata *> *topics() const {
+    return &topics_;
+  }
+
+  std::string orig_broker_name() const {
+    return std::string(metadata_->orig_broker_name);
+  }
+
+  int32_t orig_broker_id() const {
+    return metadata_->orig_broker_id;
+  }
+
+ private:
+  const rd_kafka_metadata_t *metadata_;
+  std::vector<const BrokerMetadata *> brokers_;
+  std::vector<const TopicMetadata *> topics_;
+  std::string orig_broker_name_;
+};
+
+
+
+class ConsumerImpl : virtual public Consumer, virtual public HandleImpl {
+ public:
+  ~ConsumerImpl() {
+    if (rk_)
+      rd_kafka_destroy(rk_);
+  }
+  static Consumer *create(Conf *conf, std::string &errstr);
+
+  ErrorCode start(Topic *topic, int32_t partition, int64_t offset);
+  ErrorCode start(Topic *topic,
+                  int32_t partition,
+                  int64_t offset,
+                  Queue *queue);
+  ErrorCode stop(Topic *topic, int32_t partition);
+  ErrorCode seek(Topic *topic,
+                 int32_t partition,
+                 int64_t offset,
+                 int timeout_ms);
+  Message *consume(Topic *topic, int32_t partition, int timeout_ms);
+  Message *consume(Queue *queue, int timeout_ms);
+  int consume_callback(Topic *topic,
+                       int32_t partition,
+                       int timeout_ms,
+                       ConsumeCb *cb,
+                       void *opaque);
+  int consume_callback(Queue *queue,
+                       int timeout_ms,
+                       RdKafka::ConsumeCb *consume_cb,
+                       void *opaque);
+};
+
+
+
+class ProducerImpl : virtual public Producer, virtual public HandleImpl {
+ public:
+  ~ProducerImpl() {
+    if (rk_)
+      rd_kafka_destroy(rk_);
+  }
+
+  ErrorCode produce(Topic *topic,
+                    int32_t partition,
+                    int msgflags,
+                    void *payload,
+                    size_t len,
+                    const std::string *key,
+                    void *msg_opaque);
+
+  ErrorCode produce(Topic *topic,
+                    int32_t partition,
+                    int msgflags,
+                    void *payload,
+                    size_t len,
+                    const void *key,
+                    size_t key_len,
+                    void *msg_opaque);
+
+  ErrorCode produce(Topic *topic,
+                    int32_t partition,
+                    const std::vector<char> *payload,
+                    const std::vector<char> *key,
+                    void *msg_opaque);
+
+  ErrorCode produce(const std::string topic_name,
+                    int32_t partition,
+                    int msgflags,
+                    void *payload,
+                    size_t len,
+                    const void *key,
+                    size_t key_len,
+                    int64_t timestamp,
+                    void *msg_opaque);
+
+  ErrorCode produce(const std::string topic_name,
+                    int32_t partition,
+                    int msgflags,
+                    void *payload,
+                    size_t len,
+                    const void *key,
+                    size_t key_len,
+                    int64_t timestamp,
+                    RdKafka::Headers *headers,
+                    void *msg_opaque);
+
+  ErrorCode flush(int timeout_ms) {
+    return static_cast<RdKafka::ErrorCode>(rd_kafka_flush(rk_, timeout_ms));
+  }
+
+  ErrorCode purge(int purge_flags) {
+    return static_cast<RdKafka::ErrorCode>(
+        rd_kafka_purge(rk_, (int)purge_flags));
+  }
+
+  Error *init_transactions(int timeout_ms) {
+    rd_kafka_error_t *c_error;
+
+    c_error = rd_kafka_init_transactions(rk_, timeout_ms);
+
+    if (c_error)
+      return new ErrorImpl(c_error);
+    else
+      return NULL;
+  }
+
+  Error *begin_transaction() {
+    rd_kafka_error_t *c_error;
+
+    c_error = rd_kafka_begin_transaction(rk_);
+
+    if (c_error)
+      return new ErrorImpl(c_error);
+    else
+      return NULL;
+  }
+
+  Error *send_offsets_to_transaction(
+      const std::vector<TopicPartition *> &offsets,
+      const ConsumerGroupMetadata *group_metadata,
+      int timeout_ms) {
+    rd_kafka_error_t *c_error;
+    const RdKafka::ConsumerGroupMetadataImpl *cgmdimpl =
+        dynamic_cast<const RdKafka::ConsumerGroupMetadataImpl *>(
+            group_metadata);
+    rd_kafka_topic_partition_list_t *c_offsets = partitions_to_c_parts(offsets);
+
+    c_error = rd_kafka_send_offsets_to_transaction(
+        rk_, c_offsets, cgmdimpl->cgmetadata_, timeout_ms);
+
+    rd_kafka_topic_partition_list_destroy(c_offsets);
+
+    if (c_error)
+      return new ErrorImpl(c_error);
+    else
+      return NULL;
+  }
+
+  Error *commit_transaction(int timeout_ms) {
+    rd_kafka_error_t *c_error;
+
+    c_error = rd_kafka_commit_transaction(rk_, timeout_ms);
+
+    if (c_error)
+      return new ErrorImpl(c_error);
+    else
+      return NULL;
+  }
+
+  Error *abort_transaction(int timeout_ms) {
+    rd_kafka_error_t *c_error;
+
+    c_error = rd_kafka_abort_transaction(rk_, timeout_ms);
+
+    if (c_error)
+      return new ErrorImpl(c_error);
+    else
+      return NULL;
+  }
+
+  static Producer *create(Conf *conf, std::string &errstr);
+};
+
+
+
+}  // namespace RdKafka
+
+#endif /* _RDKAFKACPP_INT_H_ */