Jaeger

Astro is able to connect to a remote Jaeger and has additional environment variables to control Jaeger options.

ENV Vars

astro.conf

At the moment, the astro.conf file has only one option.

• JAEGER_DISABLED

  • This controls whether Impulse should try to use Jaeger or not. By default this is set to false for testing purposes.

  • Set to true to stop Impulse from connecting to Jaeger. This will help clean up additional logs when Jaeger is not running.

docker-compose.yml

The remaining Jaeger environment variables are in each docker-compose.yml file. i.e., docker-tools/compose-template/impulse-core/docker-compose.yml and docker-tools/compose-template/strapi4-connector/docker-compose.yml

As a result to connect to a remote Jaeger each individual container in appropriate docker-compose.yml must have it's ENV vars updated.

• JAEGER_AGENT_HOST

  • The host to connect to Jaeger. Set this to connect to a remote Jaeger. i.e., JAEGER_AGENT_HOST=jaeger or JAEGER_AGENT_HOST=10.0.1.60

• JAEGER_AGENT_PORT

  • The port to connecto to Jaeger. Set this to connect to Jaeger. i.e.,JAEGER_AGENT_PORT=6831

• JAEGER_SAMPLER_TYPE

  • The sampler type: remote, const, probabilistic, ratelimiting (default remote). Astro automatically sets this to const

• JAEGER_SAMPLER_PARAM

  • The sampler parameter (number). Astro sets this to 1.

• JAEGER_REPORTER_MAX_QUEUE_SIZE

  • The reporter's maximum queue size (default 100). Astro sets this to 100000.

Additional ENV vars can be found in the README for the Jaeger library we use. This doc will also add additional details to the above ENV vars.

Jaeger config

Astro's Jaeger instance is controlled by the docker compose file at docker-tools/compose-template/jaeger/docker-compose.yml. This controls the Jaeger config for start and how it connects to Cassandra and such. This also is where the Jaeger Cassandra schema is created by a docker container.

For more information review the Jaeger documentation.