Optionally not running Jaeger in Docker container without failing

[typotter]

Hiya, folks.

I'm still pretty new to OpenTelemetry and distributed tracing in general, so apologies if this is the wrong place to ask or if I'm not making sense.

I am working on an application stack that runs locally in several docker containers, all brought up together with docker-compose. I wanted to set up the local configuration in such a way that running a Jaeger docker container would be optional.

In order to point a JaegerExporter at the Jaeger instance running in a docker container, I configure it with host: jaeger-container-name. To make running it optional, I've put the jaeger service in its own "tracing.yml" file and bring everything up with docker-compose -f my-app.yml -f tracing.yml up. This works great.

If, however, I don't want to run the Jaeger container when developing locally and I leave out the -f tracing.yml in the docker-compose command, the following error is raised:

{"stack":"Error: error sending spans over UDP: Error: getaddrinfo EAI_AGAIN jaeger-container-name [truncated]

It makes sense that the host can't be found since it doesn't exist. If I am developing locally and run all the services directly (with yarn), the tracing exporter is configured to post to localhost, and works just fine whether or not Jaeger is actually running locally (the host can be found and posting traces is best effort so it doesn't matter if Jaeger is actually there, listening).

Is there a way to avoid this error without writing code to directly confirm the host can be found before instantiating the JaegerExporter? Is trying to optionally omit running Jaeger locally just causing more pain than it's saving? I've gone down a few rabbit holes around similar sounding issues like this one but I've not been able to find a workable solution / this behaviour seems to be WAI.

Thanks for reading and for all you do
-Ty

[dyladan]

I would probably say just run the jaeger container locally without mounting its storage or something like that. If you really don't want to run it, Jaeger has a /health endpoint you can use to check if it is up before constructing the jaeger exporter.

[typotter]

Thanks Daniel