Upload code coverage report through CI

[tlfeng]

Is your feature request related to a problem? Please describe.
A part of issue: #850
There hasn't got a place to see the code coverage of this repository.

Describe the solution you'd like
To achieve the goal of reporting test coverage, I plan to upload the code coverage report to Codecov through CI.
We have set a plan for OpenSearch/Dashboards plugins to report the code coverage, and I'm going to expand it to the
"OpenSearch".

The report can be uploaded to Codecov daily or during the "gradle check" process of Pull Requests.

The command to generate the code coverage report: the guide in TESTING.md
Steps to upload the report to Codecov:

• If using "Github Actions" to create CI workflow, please refer to the guide in opensearch-plugins repo.
• In general, uses "Codecov Uploader", see docs and blog from Codecov.

The codecov dashboard to see all the code coverage information for opensearch-project: https://app.codecov.io/gh/opensearch-project

Describe alternatives you've considered
None.

Additional context
None.

[sampathbalivada]

I set up a GitHub Actions workflow to test things out at my end and seems like I have an issue running the tests. These are the tasks that I am running at my end. (All these are running on a replica of the main branch)

./gradlew check -Dtests.coverage=true

# the workflow run for the below task has been successful 
# because of 'true' but the build failed
./gradlew codeCoverageReport --parallel || true

./gradlew codeCoverageReportForUnitTest --parallel

All these tasks failed with the following exception.

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':server:test'.

Runs for reference:
https://github.com/sampathbalivada/OpenSearch/runs/4852410823?check_suite_focus=true
https://github.com/sampathbalivada/OpenSearch/runs/4853613540?check_suite_focus=true
https://github.com/sampathbalivada/OpenSearch/runs/4856683788?check_suite_focus=true

I am able to perform assemble and precommit tasks but not being able to generate coverage reports. My guess is that I am missing a dependency here.

The workflow installs JDK11 and runs the above command(s). I have some questions here.

• Are additional JDKs (8,11,14) required to run these tests? I only thought we need them to run backwards compatibility checks.
• Is there a dependency that I am currently missing?

[dblock]

@sampathbalivada Check out #1665, that should answer many questions. Beyond setup, ./gradlew check requires hardware that GHA can't quite handle and we've been trying several workarounds short of running our own setup (we currently do with Jenkins and a bunch of instances supplied by AWS).

[sampathbalivada]

Thank you for the information @dblock. Seems like this issue has a dependency on #39.

Also, since we are already doing ./gradlew check, wouldn't it be easier to add -Dtests.coverage=true and generate the coverage report there?

[dblock]

Also, since we are already doing ./gradlew check, wouldn't it be easier to add -Dtests.coverage=true and generate the coverage report there?

Likely!

[dreamer-89]

Code coverage report upload was handled as part of public jenkins migration work. Since, the work is already completed, closing this issue.