Fix labeler workflow for fork PRs using workflow_run pattern

.github/workflows/labeler.yml

@@ -1,31 +1,21 @@
 name: labeler
 
-on: [pull_request]
+on:
+  pull_request:
+    types: [opened, reopened, synchronize]
 
 jobs:
-  labeler:
-    permissions:
-      pull-requests: write
-      contents: read
-      issues: write
+  save-pr-number:
     runs-on: ubuntu-latest
-    name: Label the PR size
+    name: Save PR number
     steps:
-      - uses: codelytv/pr-size-labeler@4ec67706cd878fbc1c8db0a5dcd28b6bb412e85a # v1
+      - name: Save PR number
+        run: |
+          mkdir -p ./pr
+          echo ${{ github.event.pull_request.number }} > ./pr/pr_number.txt
+      - name: Upload PR number
+        uses: actions/upload-artifact@v4
         with:
-          xs_label: "size/xs"
-          xs_max_size: "10"
-          s_label: "size/s"
-          s_max_size: "100"
-          m_label: "size/m"
-          m_max_size: "500"
-          l_label: "size/l"
-          l_max_size: "1000"
-          xl_label: "size/xl"
-          fail_if_xl: "false"
-          message_if_xl: >
-            This PR exceeds the recommended size of 1000 lines.
-            Please make sure you are NOT addressing multiple issues with one PR.
-            Note this PR might be rejected due to its size.
-          github_api_url: "https://api.github.com"
-          files_to_ignore: ""
+          name: pr_number
+          path: pr/
+          retention-days: 1

.github/workflows/labeler_apply.yml

@@ -0,0 +1,149 @@
+name: labeler_apply
+
+on:
+  workflow_run:
+    workflows: ["labeler"]
+    types:
+      - completed
+
+jobs:
+  apply-labels:
+    permissions:
+      pull-requests: write
+      contents: read
+      issues: write
+    runs-on: ubuntu-latest
+    name: Apply PR size label
+    if: ${{ github.event.workflow_run.conclusion == 'success' }}
+    steps:
+      - name: Download PR number artifact
+        uses: dawidd6/action-download-artifact@bf251b5aa9c2f7eeb574a96ee720e24f801b7c11 # v6
+        with:
+          workflow: labeler.yml
+          run_id: ${{ github.event.workflow_run.id }}
+          name: pr_number
+          path: pr
+
+      - name: Read PR number
+        id: pr_number
+        run: |
+          PR_NUMBER=$(cat pr/pr_number.txt)
+          echo "pr_number=$PR_NUMBER" >> $GITHUB_OUTPUT
+
+      - name: Calculate PR size and apply label
+        uses: actions/github-script@ed597411d8f924073f98dfc5c65a23a2325f34cd # v8
+        with:
+          github-token: ${{ github.token }}
+          script: |
+            const prNumber = ${{ steps.pr_number.outputs.pr_number }};
+            const owner = context.repo.owner;
+            const repo = context.repo.repo;
+
+            // Get PR details
+            const pr = await github.rest.pulls.get({
+              owner,
+              repo,
+              pull_number: prNumber
+            });
+
+            // Get PR files to calculate size (with pagination)
+            let totalChanges = 0;
+            const iterator = github.paginate.iterator(
+              github.rest.pulls.listFiles,
+              {
+                owner,
+                repo,
+                pull_number: prNumber,
+                per_page: 100
+              }
+            );
+
+            // Calculate total changes (additions + deletions)
+            for await (const response of iterator) {
+              for (const file of response.data) {
+                totalChanges += file.additions + file.deletions;
+              }
+            }
+
+            console.log(`Total changes: ${totalChanges}`);
+
+            // Determine size label based on thresholds
+            let sizeLabel = '';
+            if (totalChanges <= 10) {
+              sizeLabel = 'size/xs';
+            } else if (totalChanges <= 100) {
+              sizeLabel = 'size/s';
+            } else if (totalChanges <= 500) {
+              sizeLabel = 'size/m';
+            } else if (totalChanges <= 1000) {
+              sizeLabel = 'size/l';
+            } else {
+              sizeLabel = 'size/xl';
+            }
+
+            console.log(`Determined size label: ${sizeLabel}`);
+
+            // Get current labels on the PR
+            const currentLabels = pr.data.labels.map(label => label.name);
+            console.log(`Current labels: ${currentLabels.join(', ')}`);
+
+            // Remove any existing size labels
+            const sizeLabels = ['size/xs', 'size/s', 'size/m', 'size/l', 'size/xl'];
+            for (const label of currentLabels) {
+              if (sizeLabels.includes(label)) {
+                console.log(`Removing old size label: ${label}`);
+                try {
+                  await github.rest.issues.removeLabel({
+                    owner,
+                    repo,
+                    issue_number: prNumber,
+                    name: label
+                  });
+                } catch (error) {
+                  // Ignore error if label doesn't exist
+                  console.log(`Could not remove label ${label}: ${error.message}`);
+                }
+              }
+            }
+
+            // Add the new size label
+            console.log(`Adding new size label: ${sizeLabel}`);
+            await github.rest.issues.addLabels({
+              owner,
+              repo,
+              issue_number: prNumber,
+              labels: [sizeLabel]
+            });
+
+            // Post warning comment if size is XL
+            if (sizeLabel === 'size/xl') {
+              const warningMessage = `This PR exceeds the recommended size of 1000 lines.
+              Please make sure you are NOT addressing multiple issues with one PR.
+              Note this PR might be rejected due to its size.`;
+
+              // Check if we've already posted this warning
+              const comments = await github.rest.issues.listComments({
+                owner,
+                repo,
+                issue_number: prNumber
+              });
+
+              const botComment = comments.data.find(comment =>
+                comment.user.type === 'Bot' &&
+                comment.body.includes('This PR exceeds the recommended size of 1000 lines')
+              );
+
+              if (!botComment) {
+                console.log('Posting XL warning comment');
+                await github.rest.issues.createComment({
+                  owner,
+                  repo,
+                  issue_number: prNumber,
+                  body: warningMessage
+                });
+              } else {
+                console.log('XL warning comment already exists');
+              }
+            }
+
+            console.log('Labeling completed successfully');