Cloud Pub/Sub C++ Client Library
The Cloud Pub/Sub C++ Client library offers types and functions to use Cloud Pub/Sub from C++ applications.
Quickstart
The following "Hello World" program should give you a sense of how to use the library.
#include "google/cloud/pubsub/publisher.h"
#include <iostream>
int main(int argc, char* argv[]) try {
if (argc != 3) {
std::cerr << "Usage: " << argv[0] << " <project-id> <topic-id>\n";
return 1;
}
std::string const project_id = argv[1];
std::string const topic_id = argv[2];
// Create a namespace alias to make the code easier to read.
namespace pubsub = ::google::cloud::pubsub;
auto publisher = pubsub::Publisher(
pubsub::MakePublisherConnection(pubsub::Topic(project_id, topic_id)));
auto id =
publisher
.Publish(pubsub::MessageBuilder{}.SetData("Hello World!").Build())
.get();
if (!id) throw std::move(id).status();
std::cout << "Hello World published with id=" << *id << "\n";
return 0;
} catch (google::cloud::Status const& status) {
std::cerr << "google::cloud::Status thrown: " << status << "\n";
return 1;
}
More Information
Publisher::Publish()
- to efficiently publish Pub/Sub messages.BlockingPublisher::Publish()
- to publish a single Pub/Sub messages.Subscriber::Subscribe()
- to asynchronous receive Pub/Sub messages.Subscriber::Pull()
- to receive a single Pub/Sub messages.- Error Handling to learn how the library reports run-time errors.
- Environment Variables for environment variables affecting the library. Some of these environment variables enable logging to the console. This can be an effective approach to diagnose runtime problems.
- Override the default endpoint
- Override the authentication configuration
- Override Retry, Backoff, and Idempotency Policies
- Testing your Cloud Pub/Sub publisher application with googlemock shows how to write tests mocking Publisher
- Testing your Cloud Pub/Sub subscriber application with googlemock shows how to write tests mocking Subscriber
- The Setting up your development environment guide describes how to set up a C++ development environment in various platforms, including the Google Cloud C++ client libraries.