Add auto-merge feature for GitHub and GitLab

[Skn0tt]

CML is a great tool! We're using it to automatically pull in new data into our repository daily. Currently, we're reviewing + merging every PR manually. We'd like to automate this, and would like to use Gitlab's auto-merge feature to do so. This PR is a first iteration on supporting this. We'll test internally, and if it works, possibly extend the feature to the GitHub driver.

[DavidGOrtega]

👋 @Skn0tt thanks for the contribution.
We have already talked about this auto-merge feature. Let's review it 😃

[0x2b3bfa0]

Note: this feature is also supported on GitHub and Bitbucket, although I have never user the latter.

[Skn0tt]

Note: this feature is also supported on GitHub and Bitbucket, although I have never user the latter.

@0x2b3bfa0 do you know of any way to programmatically enable auto-merge on GitHub? couldn't find anything in their API Docs

[0x2b3bfa0]

@0x2b3bfa0 do you know of any way to programmatically enable auto-merge on GitHub?

It's only available through GraphQL as far as I know. See enablePullRequestAutoMerge and EnablePullRequestAutoMergeInput for more information.

[0x2b3bfa0]

Would probably imply using @octokit/graphql instead of / apart from @octokit/rest

[DavidGOrtega]

Note: this feature is also supported on GitHub and Bitbucket, although I have never user the latter.

@0x2b3bfa0 do you know of any way to programmatically enable auto-merge on GitHub? couldn't find anything in their API Docs

The equivalent of what you do using octokit

[DavidGOrtega]

@0x2b3bfa0

But @Skn0tt is doing a synthetic "auto-merge" feature in GL using

const endpoint = `/projects/${projectPath}/merge_requests/${mergeRequestId}/merge`;

The equivalent is just merge as it is doing right now?
Maybe Im missing something?

[0x2b3bfa0]

Maybe Im missing something?

This pull request makes use of merge_when_pipeline_succeeds (documentation) which is the functional equivalent of GitHub auto–merge.

[DavidGOrtega]

@0x2b3bfa0 Are they the same? It seems that in GL merges if pipeline succeed I cant find that specs in the GH docs, maybe they are expecting to to additionally setup branch protection?

[0x2b3bfa0]

All these features sound pretty similar to me. 🤔

GitHub

If you enable auto-merge for a pull request, the pull request will merge automatically when all required reviews are met and status checks have passed.

GitLab

When reviewing a merge request that looks ready to merge but still has a pipeline running, you can set it to merge automatically when the pipeline succeeds. This way, you don’t have to wait for the pipeline to finish and remember to merge the request manually.

Bitbucket

Today Bitbucket is releasing a new labs feature, "Pending Merges", which allows for automatic merging of pull requests when builds pass.

[DavidGOrtega]

status checks have passed.

@0x2b3bfa0 so Am I right??

The issue that I see is that you must to upgrade then to use the feature?

[DavidGOrtega]

We should do a trial to see if it works as expected beforehand

[DavidGOrtega]

If not maybe just synthetic PR may work taking into account that merge would be the last op without having fail at least the current step in the workflow (not yet a successfully workflow)

[0x2b3bfa0]

Looks good to me! Should we keep JSDoc comments? There is no precedent in our code base, although it's a tempting improvement.

[DavidGOrtega]

Looks good to me! Should we keep JSDoc comments? There is no precedent in our code base, although it's a tempting improvement.

Good question.
If we accept it we should follow up a technical debt issue to fulfil the rest

[0x2b3bfa0]

https://gitlab.com/gitlab-org/gitlab/-/issues/353984#note_870245292

[casperdcl]

lgtm - test failing due to unrelated #914

[DavidGOrtega]

👍

[DavidGOrtega]

opens #916

[0x2b3bfa0]

[casperdcl]

Thanks @Skn0tt! Will be released soon (v0.12.0)