DockerCLI/hack/otel/README.md

Sample stack for testing OTEL functionality with the CLI

To test the OTEL functionality present in the CLI, you can spin up a small demo compose stack that includes:

• an OTEL collector container;
• a Prometheus container;
• an Aspire Dashboard container

The hack/otel directory contains the compose file with the services configured, along with 2 basic configuration files: one for the OTEL collector and one for Prometheus.

How can I use it?

1. Start the compose stack by running docker compose up -d in the hack/otel/ directory;
2. Export the env var used to override the OTLP endpoint:
   export DOCKER_CLI_OTEL_EXPORTER_OTLP_ENDPOINT=http://localhost:4317 (if running the CLI in a devcontainer or in other ways, you might have to change how you pass this env var);
3. Run the CLI to send some metrics to the endpoint;
4. Browse Prometheus at http://localhost:9091/graph or the Aspire Dashboard at http://localhost:18888/metrics;
5. In Prometheus, query command_time_milliseconds_total to see some metrics. In Aspire, select the resource in the dropdown.

Note: The precise steps may vary based on how you're working on the codebase (buiding a binary and executing natively, running/debugging in a devcontainer, running the normal CLI as usual, etc... )

Cleanup?

Run docker compose down in the hack/otel/ directory.

You can also run unset DOCKER_CLI_OTEL_EXPORTER_OTLP_ENDPOINT to get rid of the OTLP override from your environment.