This example demonstrates how to configure a C++ tracer and the Datadog agent to connect to each other over a Unix domain socket.
The tracer accepts an environment variable, DD_TRACE_AGENT_URL, whose value
may be the file path to a Unix domain socket. The tracer will connect to the
agent using the socket rather than over the network.
The Datadog agent accepts an environment variable, DD_APM_RECEIVER_SOCKET,
that is analogous to DD_TRACE_AGENT_URL, but on the listening end. See the
relevant public documentation.
This example uses docker-compose to start up a Datadog agent and a minimal
C++ tracer that will connect to each other using a Unix domain socket that the
agent will create in the local datadog-sockets/ directory.
See docker-compose.yaml for how the environment variables and directory bindings are configured.
bin/run runs the example. The environment variable DD_API_KEY
must be set to a valid Datadog API key, e.g.
$ DD_API_KEY=$(cat ~/.dd-keys/default/api-key) bin/run
Building dd-opentracing-cpp-example-unix-domain-socket
Sending build context to Docker daemon 10.75kB
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