This directory contains an idiomatic C++ client library for the Cloud Trace API, a service to send application trace data to Cloud Trace for viewing. This library is used to interact with the Trace API directly. If you are looking to instrument your application for Cloud Trace, we recommend using OpenTelemetry or a similar framework.
While this library is GA, please note that the Google Cloud C++ client libraries do not follow Semantic Versioning.
The quickstart/ directory contains a minimal environment to get started using this client library in a larger project. The following “Hello World” program is used in this quickstart, and should give you a taste of this library.
For detailed instructions on how to build and install this library, see the top-level README.
#include "google/cloud/trace/v2/trace_client.h"
#include "google/cloud/project.h"
#include <google/protobuf/util/time_util.h>
#include <iostream>
#include <random>
#include <thread>
std::string RandomHexDigits(std::mt19937_64& gen, int count) {
auto const digits = std::string{"0123456789abcdef"};
std::string sample;
std::generate_n(std::back_inserter(sample), count, [&] {
auto n = digits.size() - 1;
return digits[std::uniform_int_distribution<std::size_t>(0, n)(gen)];
});
return sample;
}
int main(int argc, char* argv[]) try {
if (argc != 2) {
std::cerr << "Usage: " << argv[0] << " project-id\n";
return 1;
}
namespace trace = ::google::cloud::trace_v2;
namespace v2 = ::google::devtools::cloudtrace::v2;
using ::google::protobuf::util::TimeUtil;
auto client = trace::TraceServiceClient(trace::MakeTraceServiceConnection());
// Create a span ID using some random hex digits.
auto gen = std::mt19937_64(std::random_device{}());
v2::Span span;
auto span_id = RandomHexDigits(gen, 16);
span.set_name(std::string{"projects/"} + argv[1] + "/traces/" +
RandomHexDigits(gen, 32) + "/spans/" + span_id);
span.set_span_id(std::move(span_id));
*span.mutable_start_time() = (TimeUtil::GetCurrentTime)();
// Simulate a call using a small sleep
std::this_thread::sleep_for(std::chrono::milliseconds(2));
*span.mutable_end_time() = (TimeUtil::GetCurrentTime)();
auto response = client.CreateSpan(span);
if (!response) throw std::move(response).status();
std::cout << response->DebugString() << "\n";
return 0;
} catch (google::cloud::Status const& status) {
std::cerr << "google::cloud::Status thrown: " << status << "\n";
return 1;
}
.h files