feat(auto-merge): create auto merge action MAPCO-9003

.github/workflows/test-auto-merge.yaml

@@ -0,0 +1,62 @@
+name: Test auto-merge action
+
+on:
+  pull_request:
+    paths:
+      - "actions/auto-merge/**"
+
+jobs:
+  test-action:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout this repo
+        uses: actions/checkout@v6
+
+      - name: Run auto-merge action
+        uses: ./actions/auto-merge
+        with:
+          pr_number: ${{ github.event.pull_request.number }}
+          github_token: ${{ secrets.GH_PAT }}
+          repository: ${{ github.repository }}
+
+  test-action-with-labels:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout this repo
+        uses: actions/checkout@v6
+
+      - name: Checkout test repo
+        uses: actions/checkout@v6
+        with:
+          repository: MapColonies/test-site
+          token: ${{ secrets.GH_PAT }}
+          ref: master
+          persist-credentials: false
+
+      - name: Create empty commit in test repo
+        run: |
+          git config user.name "GitHub Actions Bot"
+          git config user.email "actions@github.com"
+          git commit --allow-empty -m "chore: empty PR for auto-merge test (${GITHUB_SHA})"
+
+      - name: Create Pull Request
+        id: create_pr
+        uses: peter-evans/create-pull-request@v6
+        with:
+          token: ${{ secrets.GH_PAT }}
+          repository: MapColonies/test-site
+          branch: "auto-merge-e2e-${{ github.sha }}"
+          base: master
+          title: 'chore: auto-merge e2e test'
+          body: |
+            Trigger commit: https://github.com/${{ github.repository }}/commit/${{ github.sha }}
+
+            Empty commit PR for auto-merge test.
+          labels: auto-merge
+
+      - name: Run auto-merge action
+        uses: ./actions/auto-merge
+        with:
+          pr_number: ${{ steps.create_pr.outputs.pull-request-number }}
+          github_token: ${{ secrets.GH_PAT }}
+          repository: MapColonies/test-site

actions/auto-merge/README.md

@@ -0,0 +1,45 @@
+# Auto-merge PR by label
+
+Checks if a pull request has the `auto-merge` label, waits for all checks to pass, and then merges the PR.
+
+---
+
+## ✨ What It Does
+
+- Verifies the PR has the `auto-merge` label
+- Waits for all PR checks to complete and pass
+- Merges the PR with a squash strategy
+- Skips merge if the label is missing or checks fail
+
+---
+
+## 🛠 Inputs
+
+| Name | Description | Required | Default |
+|------|-------------|----------|---------|
+| `pr_number` | Pull Request number to check and merge | ✅ Yes |  |
+| `github_token` | GitHub token with permissions to merge PRs | ✅ Yes |  |
+| `repository` | Target repository in `owner/repo` format (typically `${{ github.repository }}`) | ✅ Yes |  |
+| `merge_label` | Label that triggers auto-merge (if present on the PR) | ❌ No | `auto-merge` |
+| `merge_method` | Merge method to use (merge, squash, rebase). Defaults to `squash`. | ❌ No | `squash` |
+
+
+## 🚀 Usage
+
+<!-- x-release-please-start-version -->
+
+```yaml
+permissions:
+  contents: write
+  pull-requests: write
+
+steps:
+  - name: Auto-merge PR by label
+    uses: MapColonies/shared-workflows/actions/auto-merge@auto-merge-v0.1.0
+    with:
+      pr_number: ${{ github.event.pull_request.number }}
+      github_token: ${{ secrets.GH_PAT }}
+      repository: ${{ github.repository }}
+```
+
+<!-- x-release-please-end-version -->

actions/auto-merge/action.yaml

@@ -0,0 +1,113 @@
+name: "Auto-merge PR by label"
+description: "Checks if a PR has the 'auto-merge' label and merges it using gh if present"
+
+inputs:
+  pr_number:
+    description: "Pull Request number to check and merge"
+    required: true
+  github_token:
+    description: "GitHub token with permissions to merge PRs (repo scope)"
+    required: true
+  repository:
+    description: "Target repository (owner/repo). Defaults to the current repository."
+    required: true
+  merge_label:
+    description: "Label that triggers auto-merge"
+    required: false
+    default: "auto-merge"
+  merge_method:
+    description: "Merge method to use (merge, squash, rebase). Defaults to 'squash'."
+    required: false
+    default: "squash"
+
+runs:
+  using: "composite"
+  steps:
+    - name: Install gh (for act)
+      shell: bash
+      run: |
+        if command -v gh >/dev/null; then
+          echo "gh already instlled"; exit 0;
+        fi
+        sudo apt-get update -y
+        sudo apt-get install -y git curl
+        curl -fsSL https://cli.github.com/packages/githubcli-archive-keyring.gpg \
+          | sudo tee /usr/share/keyrings/githubcli-archive-keyring.gpg >/dev/null
+        echo "deb [signed-by=/usr/share/keyrings/githubcli-archive-keyring.gpg] https://cli.github.com/packages stable main" \
+          | sudo tee /etc/apt/sources.list.d/github-cli.list >/dev/null
+        sudo apt-get update -y
+        sudo apt-get install -y gh
+
+    - name: Authenticate gh with github_token
+      shell: bash
+      env:
+        GITHUB_TOKEN: ${{ inputs.github_token }}
+        GH_TOKEN: ${{ inputs.github_token }}
+      run: |
+        set -euo pipefail
+        # If GH_TOKEN/GITHUB_TOKEN is set, gh uses it automatically; avoid forcing login.
+        if gh auth status >/dev/null 2>&1; then
+          echo "gh is already authenticated"
+        else
+          # Probe API to confirm token works; this avoids storing credentials when env vars are set.
+          if gh api user >/dev/null 2>&1; then
+            echo "gh authenticated via environment token"
+          else
+            echo "Environment token appears invalid; attempting login via --with-token"
+            echo -n "$GITHUB_TOKEN" | gh auth login --with-token
+            gh auth status
+          fi
+        fi
+
+    - name: Check for '${{ inputs.merge_label }}' label
+      id: check_label
+      shell: bash
+      env:
+        GH_TOKEN: ${{ inputs.github_token }}
+      run: |
+        set -euo pipefail
+        labels=$(gh pr view "${{ inputs.pr_number }}" --repo "${{ inputs.repository }}" --json labels -q '.labels[].name')
+
+        if grep -qx "${{ inputs.merge_label }}" <<< "$labels"; then
+          echo "has_label=true" >> "$GITHUB_OUTPUT"
+        else
+          echo "has_label=false" >> "$GITHUB_OUTPUT"
+        fi
+
+    - name: Wait for PR checks
+      id: wait_checks
+      if: steps.check_label.outputs.has_label == 'true'
+      shell: bash
+      env:
+        GH_TOKEN: ${{ inputs.github_token }}
+      run: |
+        set -euo pipefail
+        echo "Waiting for all checks on PR #${{ inputs.pr_number }} to complete"
+        if gh pr checks "${{ inputs.pr_number }}" \
+             --repo "${{ inputs.repository }}" \
+             --watch; then
+          echo "All checks completed."
+          echo "passed=true" >> "$GITHUB_OUTPUT"
+        else
+          echo "Checks did not complete successfully."
+          echo "passed=false" >> "$GITHUB_OUTPUT"
+          exit 1
+        fi
+
+    - name: Merge PR if labeled
+      if: steps.check_label.outputs.has_label == 'true' && steps.wait_checks.outputs.passed == 'true'
+      shell: bash
+      env:
+        GH_TOKEN: ${{ inputs.github_token }}
+      run: |
+        set -euo pipefail
+        echo "Merging PR #${{ inputs.pr_number }} in '${{ inputs.repository }}' (label '${{ inputs.merge_label }}' found)"
+        gh pr merge "${{ inputs.pr_number }}" \
+          --repo "${{ inputs.repository }}" \
+          --${{ inputs.merge_method }} \
+
+    - name: Skip merge (label missing)
+      if: steps.check_label.outputs.has_label != 'true'
+      shell: bash
+      run: |
+        echo "Skipping merge: PR #${{ inputs.pr_number }} in repo '${{ inputs.repository }}' does not have label '${{ inputs.merge_label }}'"

release-please-config.json

@@ -28,6 +28,11 @@
         "release-type": "simple",
         "package-name": "update-chart-version",
         "extra-files": ["README.md"]
+      },
+      "actions/auto-merge": {
+        "release-type": "simple",
+        "package-name": "auto-merge",
+        "extra-files": ["README.md"]
       }
     }
 }