x/build/maintner: store Github pull request data

[kevinburke]

If we want this to be a tool for wider use (and I think it would be good to do that), we need to store Github pull request data for projects.

Furthermore, we currently get Git commits from Gerrit CL's, we'll need to allow people to specify Github as their primary Git upstream and fetch commits from Github instead of Gerrit, and also to read some of the metadata from Github's API that we currently parse out of the Git commits in Gerrit.

[andybons]

We need the following in the maintner model for #18517 to avoid API calls to GitHub:

• Comments
• Pull Requests

[dmitshur]

If I'm not mistaken, this is done by now. PRs are returned as part of GitHubRepo.ForeachIssue calls and can be identified by the GitHubIssue.PullRequest field being true (see CL 69590).

Is there anything left to do in this issue?

[andybons]

There is some data we need in order to avoid calls to the GitHub API in GerritBot.

Number of commits, base ref, HEAD sha, etc.

https://github.com/golang/build/blob/master/cmd/gerritbot/gerritbot.go#L575

It also doesn't support PR comments.

[dmitshur]

Thanks for the update.

It also doesn't support PR comments.

To clarify, I think you mean PR reviews and PR review comments. Normal PR comments are already supported; they're identical to issue comments in nature.

[andybons]

Correct.

[gopherbot]

Change https://golang.org/cl/144699 mentions this issue: maintner: extend GitHubIssue to track Code Review Events