opentelemetry-cpp/examples/multithreaded/main.cc

89 lines
2.6 KiB
C++

// Copyright The OpenTelemetry Authors
// SPDX-License-Identifier: Apache-2.0
#include <algorithm>
#include <string>
#include <thread>
#include <utility>
#include <vector>
#include "opentelemetry/exporters/ostream/span_exporter_factory.h"
#include "opentelemetry/nostd/shared_ptr.h"
#include "opentelemetry/nostd/string_view.h"
#include "opentelemetry/sdk/resource/resource.h"
#include "opentelemetry/sdk/trace/exporter.h"
#include "opentelemetry/sdk/trace/processor.h"
#include "opentelemetry/sdk/trace/provider.h"
#include "opentelemetry/sdk/trace/simple_processor_factory.h"
#include "opentelemetry/sdk/trace/tracer_provider.h"
#include "opentelemetry/sdk/trace/tracer_provider_factory.h"
#include "opentelemetry/trace/provider.h"
#include "opentelemetry/trace/scope.h"
#include "opentelemetry/trace/span.h"
#include "opentelemetry/trace/tracer.h"
#include "opentelemetry/trace/tracer_provider.h"
namespace trace_api = opentelemetry::trace;
namespace trace_sdk = opentelemetry::sdk::trace;
namespace
{
void InitTracer()
{
auto exporter = opentelemetry::exporter::trace::OStreamSpanExporterFactory::Create();
auto processor = trace_sdk::SimpleSpanProcessorFactory::Create(std::move(exporter));
std::shared_ptr<opentelemetry::trace::TracerProvider> provider =
trace_sdk::TracerProviderFactory::Create(std::move(processor),
opentelemetry::sdk::resource::Resource::Create({}));
// Set the global trace provider
trace_sdk::Provider::SetTracerProvider(provider);
}
void CleanupTracer()
{
std::shared_ptr<opentelemetry::trace::TracerProvider> none;
trace_sdk::Provider::SetTracerProvider(none);
}
opentelemetry::nostd::shared_ptr<trace_api::Tracer> get_tracer()
{
auto provider = trace_api::Provider::GetTracerProvider();
return provider->GetTracer("foo_library");
}
} // namespace
void run_threads()
{
auto thread_span = get_tracer()->StartSpan(__func__);
std::vector<std::thread> threads;
threads.reserve(5);
for (int thread_num = 0; thread_num < 5; ++thread_num)
{
// This shows how one can effectively use Scope objects to correctly
// parent spans across threads.
threads.push_back(std::thread([=] {
trace_api::Scope scope(thread_span);
auto thread_span_2 =
get_tracer()->StartSpan(std::string("thread ") + std::to_string(thread_num));
}));
}
std::for_each(threads.begin(), threads.end(), [](std::thread &th) { th.join(); });
}
int main(int /* argc */, char ** /* argv */)
{
InitTracer();
{
auto root_span = get_tracer()->StartSpan(__func__);
trace_api::Scope scope(root_span);
run_threads();
}
CleanupTracer();
return 0;
}