assign-milestone-on-close.yml

name: Assign Milestone on Close

env:
  MILESTONE_ID: 1

on:
  issues:
    types: [closed]
  pull_request_target:
    types: [closed]

permissions:
  issues: write
  pull-requests: write

jobs:
  assign-milestone:
    runs-on: ubuntu-latest
    steps:
      - name: Get payload content
        id: payload-content
        uses: actions/github-script@v7
        with:
          script: console.log(JSON.stringify(context.payload));
          # result-encoding: string
      # - name: Print payload content
        # id: print-payload
        # run: |
          # echo "${{steps.get-payload.outputs.result}}" >> payload.txt
      - name: Check if milestone is set
        id: check-milestone
        uses: actions/github-script@v7
        with:
          github-token: ${{secrets.GITHUB_TOKEN}}
          script: |
            const issueOrPr = context.payload.issue || context.payload.pull_request;
            if (!issueOrPr.milestone) {
              core.setOutput('milestoneNotSet', 'true');
              console.log("Milestone not set");
            } else {
              core.setOutput('milestoneNotSet', 'false');
              console.log("Milestone already set.");
            }

      - name: Check completed or merged
        id: check-done
        uses: actions/github-script@v7
        with:
          github-token: ${{secrets.GITHUB_TOKEN}}
          script: |
            // No need to check if this is a merged PR, as pull_request_target takes care of that for us.
            if (context.payload.issue && context.payload.issue.state_reason === "completed") {
              core.setOutput('isDone', 'true');
              console.log("Done.");
            } else {
              core.setOutput('isDone', 'false');
              console.log("Not done.");
            }
            console.log(context.payload.pull_request.merged)

      - name: Assign default milestone
        if: steps.check-milestone.outputs.milestoneNotSet == 'true' && steps.check-done.outputs.isDone== 'true'
        uses: actions/github-script@v7
        with:
          github-token: ${{secrets.GITHUB_TOKEN}}
          script: |
            const issueOrPrNumber = (context.payload.issue || context.payload.pull_request).number;
            const repository = context.repo;
            await github.rest.issues.update({
              ...repository,
              issue_number: issueOrPrNumber,
              milestone: process.env.MILESTONE_ID
            });