Optional environment variable specifying the branch name to search for deployments

[ykokw]

First of all, thank you for this useful action!

Is your feature request related to a problem? Please describe.

When a comment on a pull request triggers a workflow, it is not possible to specify a branch name to search for deployments in Vercel.

Considering the cost of execution, I would like to run E2E tests only once against Vercel's Preview Deployment before requesting a code review, instead of launching tests on every commit. （For example, I do not want to start E2E testing just by adding a unit test case.）

Describe the solution you'd like

If I could specify the branch name in an additional environment variable, I would be able to retrieve the commented pull request branch in a separate job and search for deployments.

Additional context

I have already created a fork and a test repository so you can see what kind of workflow I am trying to build

• changes to add optional environment vars: https://github.com/ykokw/vercel-preview-url/commit/5e4a9608e475753c1bcbf77c78ecb06f752db41a
• test workflow: https://github.com/ykokw/vercel-preview-url-test/blob/main/.github/workflows/playwright.yml

[PatrickHeneise]

Hi @ykokw ! Thanks for raising the issue.

I've seen this done with comments or labels, for example you'd comment /deploy and have a script in the action to build/deploy/run tests only then, instead of push. Another option would be to set a specific label to run tests.

If you can provide a PR that doesn't break / change the way it's picking the current branch, but "overwrites" the branch if the environment variable is set, I can merge that.

[ykokw]

@PatrickHeneise Thank you for your response.

I have prepared a PR and would be happy to review it when you are available.