1 files changed, 186 insertions, 0 deletions
diff --git a/exporting/prometheus/remote_write/remote_write_request.cc b/exporting/prometheus/remote_write/remote_write_request.cc
new file mode 100644
index 000000000..48d19efd6
--- /dev/null
+++ b/exporting/prometheus/remote_write/remote_write_request.cc
@@ -0,0 +1,186 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#include <snappy.h>
+#include "remote_write.pb.h"
+#include "remote_write_request.h"
+
+using namespace prometheus;
+
+google::protobuf::Arena arena;
+
+/**
+ * Initialize a write request
+ *
+ * @return Returns a new write request
+ */
+void *init_write_request()
+{
+    GOOGLE_PROTOBUF_VERIFY_VERSION;
+    WriteRequest *write_request = google::protobuf::Arena::CreateMessage<WriteRequest>(&arena);
+    return (void *)write_request;
+}
+
+/**
+ * Adds information about a host to a write request
+ *
+ * @param write_request_p the write request
+ * @param name the name of a metric which is used for providing the host information
+ * @param instance the name of the host itself
+ * @param application the name of a program which sends the information
+ * @param version the version of the program
+ * @param timestamp the timestamp for the metric in milliseconds
+ */
+void add_host_info(
+    void *write_request_p,
+    const char *name, const char *instance, const char *application, const char *version, const int64_t timestamp)
+{
+    WriteRequest *write_request = (WriteRequest *)write_request_p;
+    TimeSeries *timeseries;
+    Sample *sample;
+    Label *label;
+
+    timeseries = write_request->add_timeseries();
+
+    label = timeseries->add_labels();
+    label->set_name("__name__");
+    label->set_value(name);
+
+    label = timeseries->add_labels();
+    label->set_name("instance");
+    label->set_value(instance);
+
+    if (application) {
+        label = timeseries->add_labels();
+        label->set_name("application");
+        label->set_value(application);
+    }
+
+    if (version) {
+        label = timeseries->add_labels();
+        label->set_name("version");
+        label->set_value(version);
+    }
+
+    sample = timeseries->add_samples();
+    sample->set_value(1);
+    sample->set_timestamp(timestamp);
+}
+
+/**
+ * Adds a label to the last created timeseries
+ *
+ * @param write_request_p the write request with the timeseries
+ * @param key the key of the label
+ * @param value the value of the label
+ */
+void add_label(void *write_request_p, char *key, char *value)
+{
+    WriteRequest *write_request = (WriteRequest *)write_request_p;
+    TimeSeries *timeseries;
+    Label *label;
+
+    timeseries = write_request->mutable_timeseries(write_request->timeseries_size() - 1);
+
+    label = timeseries->add_labels();
+    label->set_name(key);
+    label->set_value(value);
+}
+
+/**
+ * Adds a metric to a write request
+ *
+ * @param write_request_p the write request
+ * @param name the name of the metric
+ * @param chart the chart, the metric belongs to
+ * @param family the family, the metric belongs to
+ * @param dimension the dimension, the metric belongs to
+ * @param instance the name of the host, the metric belongs to
+ * @param value the value of the metric
+ * @param timestamp the timestamp for the metric in milliseconds
+ */
+void add_metric(
+    void *write_request_p,
+    const char *name, const char *chart, const char *family, const char *dimension, const char *instance,
+    const double value, const int64_t timestamp)
+{
+    WriteRequest *write_request = (WriteRequest *)write_request_p;
+    TimeSeries *timeseries;
+    Sample *sample;
+    Label *label;
+
+    timeseries = write_request->add_timeseries();
+
+    label = timeseries->add_labels();
+    label->set_name("__name__");
+    label->set_value(name);
+
+    label = timeseries->add_labels();
+    label->set_name("chart");
+    label->set_value(chart);
+
+    label = timeseries->add_labels();
+    label->set_name("family");
+    label->set_value(family);
+
+    if (dimension) {
+        label = timeseries->add_labels();
+        label->set_name("dimension");
+        label->set_value(dimension);
+    }
+
+    label = timeseries->add_labels();
+    label->set_name("instance");
+    label->set_value(instance);
+
+    sample = timeseries->add_samples();
+    sample->set_value(value);
+    sample->set_timestamp(timestamp);
+}
+
+/**
+ * Gets the size of a write request
+ *
+ * @param write_request_p the write request
+ * @return Returns the size of the write request
+ */
+size_t get_write_request_size(void *write_request_p)
+{
+    WriteRequest *write_request = (WriteRequest *)write_request_p;
+
+#if GOOGLE_PROTOBUF_VERSION < 3001000
+    size_t size = (size_t)snappy::MaxCompressedLength(write_request->ByteSize());
+#else
+    size_t size = (size_t)snappy::MaxCompressedLength(write_request->ByteSizeLong());
+#endif
+
+    return (size < INT_MAX) ? size : 0;
+}
+
+/**
+ * Packs a write request into a buffer and clears the request
+ *
+ * @param write_request_p the write request
+ * @param buffer a buffer, where compressed data is written
+ * @param size gets the size of the write request, returns the size of the compressed data
+ * @return Returns 0 on success, 1 on failure
+ */
+int pack_and_clear_write_request(void *write_request_p, char *buffer, size_t *size)
+{
+    WriteRequest *write_request = (WriteRequest *)write_request_p;
+    std::string uncompressed_write_request;
+
+    if (write_request->SerializeToString(&uncompressed_write_request) == false)
+        return 1;
+    write_request->clear_timeseries();
+    snappy::RawCompress(uncompressed_write_request.data(), uncompressed_write_request.size(), buffer, size);
+
+    return 0;
+}
+
+/**
+ * Shuts down the Protobuf library
+ */
+void protocol_buffers_shutdown()
+{
+    google::protobuf::ShutdownProtobufLibrary();
+}