Overview

The code coverage tool has two major features:

1. As a pre-submit tool, it runs code coverage on every single commit to Github and reports coverage changes back to the PR as a comment by a robot account. If made a required job on the repository, it can be used to block a PR from merging if coverage falls below a certain threshold.
2. As a periodic running job, it outputs a Junit XML that can be read from other tools like TestGrid to get overall coverage metrics.

Design

See the design document.

Build and Release

Run make coverage-dev-image to build and upload a staging version, intended for testing and debugging. The staging version can be triggered on a PR through the comment /test pull-knative-serving-go-coverage-dev. Note that staging version can only be tested against the serving repository because the staging jobs only exist in the serving repository.

Validating the staging version

• To run the pre-submit workflow, add the comment /test pull-knative-serving-go-coverage-dev to a PR.
• To run the periodic workflow, (re)run a post-knative-serving-go-coverage-dev job.

To publish a new version of the code coverage tool, run make coverage-image.