Getting Started • Getting Involved

Splunk Distribution of OpenTelemetry C++

The Splunk Distribution of OpenTelemetry C++ is a wrapper that comes with defaults suitable to report distributed traces to Splunk APM.

This distribution comes with the following defaults:

W3C tracecontext context propagation; B3 can also be configured.
OTLP exporter configured to send spans to a locally running Splunk OpenTelemetry Connector (http://localhost:4317);

🚧 This project is currently in BETA. It is officially supported by Splunk. However, breaking changes MAY be introduced.

Getting Started

Clone the repository along with submodules

$ git clone --recurse-submodules https://github.com/signalfx/splunk-otel-cpp.git

Build the dependencies and the project

$ ./build_deps.sh -DCMAKE_INSTALL_PREFIX=/path/to/splunk-otel-cpp-install
$ mkdir build
$ cd build
$ cmake -DCMAKE_INSTALL_PREFIX=/path/to/splunk-otel-cpp-install ..
$ make install

When using CMake, find the Splunk OpenTelemetry package at /path/to/splunk-otel-cpp-install

find_package(SplunkOpenTelemetry REQUIRED)
add_program(example example.cpp)
target_link_libraries(example ${SplunkOpenTelemetry_LIBRARIES})
target_include_directories(example ${SplunkOpenTelemetry_INCLUDE_DIRS})

(Optional) Using Conan package manager with CMake

Update your conanfile.txt:

[requires]
splunk-opentelemetry-cpp/0.4.0

[generators]
cmake_find_package
cmake_paths

Add include(${CMAKE_BINARY_DIR}/conan_paths.cmake) to your CMakeLists.txt
Add find_package(SplunkOpenTelemetry REQUIRED) lines described earlier.
mkdir build && cd build && conan install .. && cmake .. && make

Use it

#include <splunk/opentelemetry.h>

int main(int argc, char** argv) {
  splunk::OpenTelemetryOptions options =
    splunk::OpenTelemetryOptions()
      .WithServiceName("my-service");

  splunk::InitOpenTelemetry(options);

  // Use the usual OpenTelemetry API
  auto tracer = opentelemetry::trace::Provider::GetTraceProvider()->GetTracer("my-tracer");
  auto span = tracer->StartSpan("operation-name");

  // Do something useful
  span->End();

  return 0;
}

For more examples, see the examples directory.

Configuration options

Via environment variables

Note: options passed via splunk::OpenTelemetryOptions take preference over environment variables.

Environment variable	Default value	Notes
OTEL_SERVICE_NAME	`unknown_service`	Service name of the application
OTEL_RESOURCE_ATTRIBUTES	none	Comma separated list of Resource attributes. For example `OTEL_RESOURCE_ATTRIBUTES=service.name=foo,deployment.environment=production`
OTEL_PROPAGATORS	`tracecontext,baggage`	Comma separated list of propagators to use. Possible values: `tracecontext`, `b3`, `b3multi`, `baggage`
OTEL_TRACES_EXPORTER	`otlp`	Trace exporter to use. Possible values: `otlp`, `jaeger-thrift-splunk`.
OTEL_EXPORTER_OTLP_PROTOCOL	`grpc`	OTLP transport to use. Possible values: `grpc`.
OTEL_EXPORTER_OTLP_ENDPOINT	`localhost:4317` (gRPC) or `http://localhost:4317/v1/traces`
OTEL_EXPORTER_JAEGER_ENDPOINT	`http://localhost:9080/v1/trace`	Needs to be compiled with Jaeger support
SPLUNK_ACCESS_TOKEN	none	Only required when Splunk OpenTelemetry Connector is not used.

Requirements

C++11 capable compiler
Linux (Windows support coming)

License and versioning

The Splunk Distribution of OpenTelemetry C++ is a distribution of the OpenTelemetry C++ project. It is released under the terms of the Apache Software License version 2.0. See the license file for more details.

someone9388 / splunk-otel-cpp