Integration testing googlecloudexporter against real APIs

[aabmass]

Hi folks, we (Google) would like to do integration/e2e testing of our googlecloudexporter against the real Cloud Monitoring and Cloud Trace APIs. I have looked around the collector a bit and not found anything exactly like this. The most similar things I've found are

• tests for receivers that scrape from a docker image, like redis_e2e_test.go
• test for exporters that write to a mock API in testbed
• AWS has AOT Testing Framework which appears to run these tests off-band from other PRs?

To implement this, we are currently planning to move the googlecloudexporter code into a Google owned repo and running these integration tests on every PR to that repo. Then in collector-contrib, we will only import the code from the Google owned repository and call NewFactory as a thin wrapper. We plan to use Google Cloud Build to run these tests, which gives access to a service account and permission to write to the APIs without having to store/rotate secret keys. We expect the tests should not take more than 10 minutes to run.

Questions:

• Are there any existing tests like this that I've missed? Are any other telemetry backends doing this?
• Does the approach of moving the googlecloudexporter code out of this repo seem OK? I wanted to run this by the community to see if there are any thoughts or comments on the approach with an extra layer of indirection.
• As an alternative, would the community be open to installing Cloud Build triggers on the collector-contrib repo to run the tests on relevant PRs to the googlecloudexporter? There are some caveats here, like build logs are only accessible to people with access to the GCP project, so we'd have to manually share them.

Thanks! cc @punya @jsuereth @dashpole