Support exporting tracing data to oc_agent, then to datadog agent

[gitlw]

This change is 

[martinmr]

Reviewable status: 0 of 2 files reviewed, 2 unresolved discussions (waiting on @gitlw and @manishrjain)

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ocagent/docker-compose.yml, line 73 at r1 (raw file):

volumes: {}
        

nit: new line

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ocagent/ocagent-config.yaml, line 9 at r1 (raw file):

    namespace: "oc_pool"
    trace_addr: "datadog:8126"
    enable_tracing: true

nit: new line

[danielmai]

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ocagent/docker-compose.yml, line 17 at r2 (raw file):

--jaeger.collector=http://ocagent:14268

Does this work? I thought supporting the OpenCensus Agent requires a code change to export to the agent instead of Jaeger.

[gitlw]

Reviewable status: 0 of 2 files reviewed, 1 unresolved discussion (waiting on @danielmai and @manishrjain)

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ocagent/docker-compose.yml, line 17 at r2 (raw file):

Previously, danielmai (Daniel Mai) wrote…

--jaeger.collector=http://ocagent:14268

Does this work? I thought supporting the OpenCensus Agent requires a code change to export to the agent instead of Jaeger.

Yes, because the ocagent supports jaeger format receivers, as shown in the yaml config file in this PR.

[danielmai]

Reviewed 1 of 2 files at r1, 1 of 1 files at r2, 1 of 1 files at r3.
Reviewable status: all files reviewed, 2 unresolved discussions (waiting on @gitlw and @manishrjain)

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ocagent/docker-compose.yml, line 17 at r2 (raw file):

Previously, gitlw (Lucas Wang) wrote…

Yes, because the ocagent supports jaeger format receivers, as shown in the yaml config file in this PR.

Interesting that this works. I think it's still worth migrating to the ocagent exporter to export both traces and metrics to different backends. That can be done in another PR.

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ocagent/docker-compose.yml, line 66 at r3 (raw file):

      read_only: true
    environment:
    - DD_API_KEY=<key goes here>

This can just be - DD_API_KEY so that the environment variable can be picked up from the shell running docker-compose without modifying this docker-compose.yml.

https://docs.docker.com/compose/environment-variables/#pass-environment-variables-to-containers

[danielmai]

One more comment from me. The rest LGTM.

Reviewable status: all files reviewed, 2 unresolved discussions (waiting on @gitlw and @manishrjain)