diff options
Diffstat (limited to 'exporting/pubsub/pubsub_publish.cc')
| -rw-r--r-- | exporting/pubsub/pubsub_publish.cc | 258 |
1 files changed, 258 insertions, 0 deletions
diff --git a/exporting/pubsub/pubsub_publish.cc b/exporting/pubsub/pubsub_publish.cc new file mode 100644 index 0000000..cc14154 --- /dev/null +++ b/exporting/pubsub/pubsub_publish.cc @@ -0,0 +1,258 @@ +// SPDX-License-Identifier: GPL-3.0-or-later + +#include <google/pubsub/v1/pubsub.grpc.pb.h> +#include <grpcpp/grpcpp.h> +#include <stdexcept> +#include "pubsub_publish.h" + +#define EVENT_CHECK_TIMEOUT 50 + +struct response { + grpc::ClientContext *context; + google::pubsub::v1::PublishResponse *publish_response; + size_t tag; + grpc::Status *status; + + size_t published_metrics; + size_t published_bytes; +}; + +static inline void copy_error_message(char *error_message_dst, const char *error_message_src) +{ + std::strncpy(error_message_dst, error_message_src, ERROR_LINE_MAX); + error_message_dst[ERROR_LINE_MAX] = '\0'; +} + +/** + * Initialize a Pub/Sub client and a data structure for responses. + * + * @param pubsub_specific_data_p a pointer to a structure with instance-wide data. + * @param error_message report error message to a caller. + * @param destination a Pub/Sub service endpoint. + * @param credentials_file a full path for a file with google application credentials. + * @param project_id a project ID. + * @param topic_id a topic ID. + * @return Returns 0 on success, 1 on failure. + */ +int pubsub_init( + void *pubsub_specific_data_p, char *error_message, const char *destination, const char *credentials_file, + const char *project_id, const char *topic_id) +{ + struct pubsub_specific_data *connector_specific_data = (struct pubsub_specific_data *)pubsub_specific_data_p; + + try { + setenv("GOOGLE_APPLICATION_CREDENTIALS", credentials_file, 0); + + std::shared_ptr<grpc::ChannelCredentials> credentials = grpc::GoogleDefaultCredentials(); + if (credentials == nullptr) { + copy_error_message(error_message, "Can't load credentials"); + return 1; + } + + std::shared_ptr<grpc::Channel> channel = grpc::CreateChannel(destination, credentials); + + google::pubsub::v1::Publisher::Stub *stub = new google::pubsub::v1::Publisher::Stub(channel); + if (!stub) { + copy_error_message(error_message, "Can't create a publisher stub"); + return 1; + } + + connector_specific_data->stub = stub; + + google::pubsub::v1::PublishRequest *request = new google::pubsub::v1::PublishRequest; + connector_specific_data->request = request; + ((google::pubsub::v1::PublishRequest *)(connector_specific_data->request)) + ->set_topic(std::string("projects/") + project_id + "/topics/" + topic_id); + + grpc::CompletionQueue *cq = new grpc::CompletionQueue; + connector_specific_data->completion_queue = cq; + + connector_specific_data->responses = new std::list<struct response>; + + return 0; + } catch (std::exception const &ex) { + std::string em(std::string("Standard exception raised: ") + ex.what()); + copy_error_message(error_message, em.c_str()); + return 1; + } + + return 0; +} + +/** + * Clean the PubSub connector instance specific data + */ +void pubsub_cleanup(void *pubsub_specific_data_p) +{ + struct pubsub_specific_data *connector_specific_data = (struct pubsub_specific_data *)pubsub_specific_data_p; + + std::list<struct response> *responses = (std::list<struct response> *)connector_specific_data->responses; + std::list<struct response>::iterator response; + for (response = responses->begin(); response != responses->end(); ++response) { + // TODO: If we do this, there are a huge amount of possibly lost records. We need to find a right way of + // cleaning up contexts + // delete response->context; + delete response->publish_response; + delete response->status; + } + delete responses; + + ((grpc::CompletionQueue *)connector_specific_data->completion_queue)->Shutdown(); + delete (grpc::CompletionQueue *)connector_specific_data->completion_queue; + delete (google::pubsub::v1::PublishRequest *)connector_specific_data->request; + delete (google::pubsub::v1::Publisher::Stub *)connector_specific_data->stub; + + // TODO: Find how to shutdown grpc gracefully. grpc_shutdown() doesn't seem to work. + // grpc_shutdown(); + + return; +} + +/** + * Add data to a Pub/Sub request message. + * + * @param pubsub_specific_data_p a pointer to a structure with instance-wide data. + * @param data a text buffer with metrics. + * @return Returns 0 on success, 1 on failure. + */ +int pubsub_add_message(void *pubsub_specific_data_p, char *data) +{ + struct pubsub_specific_data *connector_specific_data = (struct pubsub_specific_data *)pubsub_specific_data_p; + + try { + google::pubsub::v1::PubsubMessage *message = + ((google::pubsub::v1::PublishRequest *)(connector_specific_data->request))->add_messages(); + if (!message) + return 1; + + message->set_data(data); + } catch (std::exception const &ex) { + return 1; + } + + return 0; +} + +/** + * Send data to the Pub/Sub service + * + * @param pubsub_specific_data_p a pointer to a structure with client and request outcome information. + * @param error_message report error message to a caller. + * @param buffered_metrics the number of metrics we are going to send. + * @param buffered_bytes the number of bytes we are going to send. + * @return Returns 0 on success, 1 on failure. + */ +int pubsub_publish(void *pubsub_specific_data_p, char *error_message, size_t buffered_metrics, size_t buffered_bytes) +{ + struct pubsub_specific_data *connector_specific_data = (struct pubsub_specific_data *)pubsub_specific_data_p; + + try { + grpc::ClientContext *context = new grpc::ClientContext; + + std::unique_ptr<grpc::ClientAsyncResponseReader<google::pubsub::v1::PublishResponse> > rpc( + ((google::pubsub::v1::Publisher::Stub *)(connector_specific_data->stub)) + ->AsyncPublish( + context, (*(google::pubsub::v1::PublishRequest *)(connector_specific_data->request)), + ((grpc::CompletionQueue *)(connector_specific_data->completion_queue)))); + + struct response response; + response.context = context; + response.publish_response = new google::pubsub::v1::PublishResponse; + response.tag = connector_specific_data->last_tag++; + response.status = new grpc::Status; + response.published_metrics = buffered_metrics; + response.published_bytes = buffered_bytes; + + rpc->Finish(response.publish_response, response.status, (void *)response.tag); + + ((google::pubsub::v1::PublishRequest *)(connector_specific_data->request))->clear_messages(); + + ((std::list<struct response> *)(connector_specific_data->responses))->push_back(response); + } catch (std::exception const &ex) { + std::string em(std::string("Standard exception raised: ") + ex.what()); + copy_error_message(error_message, em.c_str()); + return 1; + } + + return 0; +} + +/** + * Get results from service responses + * + * @param pubsub_specific_data_p a pointer to a structure with instance-wide data. + * @param error_message report error message to a caller. + * @param sent_metrics report to a caller how many metrics was successfully sent. + * @param sent_bytes report to a caller how many bytes was successfully sent. + * @param lost_metrics report to a caller how many metrics was lost during transmission. + * @param lost_bytes report to a caller how many bytes was lost during transmission. + * @return Returns 0 if all data was sent successfully, 1 when data was lost on transmission. + */ +int pubsub_get_result( + void *pubsub_specific_data_p, char *error_message, + size_t *sent_metrics, size_t *sent_bytes, size_t *lost_metrics, size_t *lost_bytes) +{ + struct pubsub_specific_data *connector_specific_data = (struct pubsub_specific_data *)pubsub_specific_data_p; + std::list<struct response> *responses = (std::list<struct response> *)connector_specific_data->responses; + grpc::CompletionQueue::NextStatus next_status; + + *sent_metrics = 0; + *sent_bytes = 0; + *lost_metrics = 0; + *lost_bytes = 0; + + try { + do { + std::list<struct response>::iterator response; + void *got_tag; + bool ok = false; + + auto deadline = std::chrono::system_clock::now() + std::chrono::milliseconds(50); + next_status = (*(grpc::CompletionQueue *)(connector_specific_data->completion_queue)) + .AsyncNext(&got_tag, &ok, deadline); + + if (next_status == grpc::CompletionQueue::GOT_EVENT) { + for (response = responses->begin(); response != responses->end(); ++response) { + if ((void *)response->tag == got_tag) + break; + } + + if (response == responses->end()) { + copy_error_message(error_message, "Cannot get Pub/Sub response"); + return 1; + } + + if (ok && response->publish_response->message_ids_size()) { + *sent_metrics += response->published_metrics; + *sent_bytes += response->published_bytes; + } else { + *lost_metrics += response->published_metrics; + *lost_bytes += response->published_bytes; + response->status->error_message().copy(error_message, ERROR_LINE_MAX); + error_message[ERROR_LINE_MAX] = '\0'; + } + + delete response->context; + delete response->publish_response; + delete response->status; + responses->erase(response); + } + + if (next_status == grpc::CompletionQueue::SHUTDOWN) { + copy_error_message(error_message, "Completion queue shutdown"); + return 1; + } + + } while (next_status == grpc::CompletionQueue::GOT_EVENT); + } catch (std::exception const &ex) { + std::string em(std::string("Standard exception raised: ") + ex.what()); + copy_error_message(error_message, em.c_str()); + return 1; + } + + if (*lost_metrics) { + return 1; + } + + return 0; +} |