This action attaches the next open milestone to merged PRs.

Currently, this action only looks at milestones that can be parsed as version numbers.

A typical job would look like this:

# .github/workflows/milestone-merged-prs.yaml

name: Milestone

on:
  pull_request_target:
    types:
      - closed
    branches:
      - 'main'

jobs:
  milestone_pr:
    name: attach to PR
    if: github.event.pull_request.merged == true
    runs-on: ubuntu-latest
    steps:
      - uses: scientific-python/attach-next-milestone-action@a4889cfde7d2578c1bc7400480d93910d2dd34f6
        with:
          token: ${{ secrets.MILESTONE_LABELER_TOKEN }}

To use the above, you will need to set a repository secret MILESTONE_LABELER_TOKEN to a fine-grained access token that has permissions to modify PRs. If you are generating a token for your org, you first need to enable fine-grained access tokens at https://github.com/organizations/<YOUR-ORGANIZATION>/settings/personal-access-tokens-onboarding.

You can generate the token itself at https://github.com/settings/apps.

1. Personal access tokens -> Fine-grained tokens. Generate new token.
2. Select the org which owns the code repository. If you don't see your organization listed, you first need to onboard it.
3. Choose "Only Select Repositories", and choose the correct one.
4. Permissions: Repository Permissions -> Pull Requests. Access: Read and write.
5. Generate the token. If an error appears saying "Sorry, something went wrong", ignore it.

Copy the token, and navigate to your code repository. Under Settings -> Secrets and variables -> Actions, add a repository secret named MILESTONE_LABELER_TOKEN, and set its contents to the generated token.

In the with clause, the following options are available:

• force: true : Overwrite existing milestones.

The workflow above runs as pull_request_target, meaning it has access to repository secrets. This is not usually a problem, since our action does nothing but attach a milestone to a PR using the provided token. But, you should not add further commands to the workflow, such as checking out the PR and executing code from it. If you do that, PR authors can gain access to your secrets.