feat: add PR expire reusable workflow (#41)

.github/workflows/expire.yml

@@ -0,0 +1,75 @@
+name: 'expire'
+
+on:
+  workflow_call:
+    inputs:
+      owner:
+        description: 'The GitHub organization or repository owner.'
+        type: 'string'
+        required: true
+      repo:
+        description: 'The repository name.'
+        type: 'string'
+        required: true
+      expiryHours:
+        description: 'The number of hours to keep an AOD PR open since last updated.'
+        type: 'number'
+        default: 24
+        required: false
+
+permissions:
+  pull-requests: 'write'
+
+jobs:
+  expire:
+    runs-on: 'ubuntu-latest'
+    steps:
+      - uses: 'actions/github-script@98814c53be79b1d30f795b907e553d8679345975' # ratchet:actions/github-script@v6
+        with:
+          result-encoding: 'string'
+          retries: 3
+          script: |-
+            const cutoffMs = ${{ inputs.expiryHours }} * 60 * 60 * 1000
+            const now = new Date();
+            const pulls = await github.rest.pulls.list({
+              owner: '${{ inputs.owner }}',
+              repo: '${{ inputs.repo }}',
+              state: 'open',
+              per_page: 100,
+            });
+
+            if (!pulls) {
+              return;
+            }
+
+            core.info(`Found ${pulls.data.length} pulls`);
+
+            pulls.data.forEach(async (pull) => {
+              const files = await github.rest.pulls.listFiles({
+                owner: '${{ inputs.owner }}',
+                repo: '${{ inputs.repo }}',
+                pull_number: pull['number'],
+              })
+
+              // Check if the PR is an AOD request by checking the AOD file existence.
+              if (files.data.find(f => f.filename === 'iam.yaml')) {
+                // Check if the PR is within the cutoff threshold
+                const updatedAt = new Date(Date.parse(pull['updated_at']));
+
+                if (now.getTime() - updatedAt.getTime() < cutoffMs) {
+                  core.info(`Skipping #${pull['number']} (${pull['title']}) - within threshold`);
+                  return;
+                }
+
+                core.info(`Closing #${pull['number']} (${pull['title']})`);
+
+                await github.rest.pulls.update({
+                  owner: '${{ inputs.owner }}',
+                  repo: '${{ inputs.repo }}',
+                  pull_number: pull['number'],
+                  state: 'closed',
+                });
+              } else {
+                core.info(`Skipping #${pull['number']} (${pull['title']}) - not an AOD request`);
+              }
+            });