chore: Retrieve correct commits for OpenAPI docs sync (#19179)

.github/workflows/sync-public-api-docs.yml

@@ -22,10 +22,13 @@ jobs:
     runs-on: ubuntu-latest
     permissions:
       contents: read
+      actions: read # Needed for `gh` to read the workflow history
 
     steps:
       - name: Checkout Main n8n Repository
         uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+        with:
+          fetch-depth: 0 # Fetch all history for git log
 
       - name: Setup PNPM
         uses: pnpm/action-setup@a7487c7e89a18df4991f7f222e4898a00d66ddda # v4.1.0
@@ -82,28 +85,54 @@ jobs:
           echo "Copying 'packages/cli/dist/public-api/v1/openapi.yml' to '${DOCS_TARGET_PATH}'"
           cp packages/cli/dist/public-api/v1/openapi.yml "${DOCS_TARGET_PATH}"
 
-      - name: Extract PR number from commit message
+      - name: Find Relevant Source Commits
+        id: find_source_commits
         if: steps.verify_file.outputs.file_exists == 'true'
-        id: extract_pr
+        env:
+          GH_TOKEN: ${{ github.token }}
         run: |
-          COMMIT_MESSAGE=$(git log -1 --pretty=%s)
-          echo "Commit message: $COMMIT_MESSAGE"
-          
-          # Extract PR number from commit message (format: "title (#1234)")
-          PR_NUMBER=$(echo "$COMMIT_MESSAGE" | grep -om1E '\(#[0-9]+\)' | grep -oE '[0-9]+' || echo "")
-          
-          if [ -n "$PR_NUMBER" ]; then
-            echo "Found PR number: $PR_NUMBER"
-            echo "pr_number=$PR_NUMBER" >> "$GITHUB_OUTPUT"
-            echo "pr_url=https://github.com/${{ github.repository }}/pull/$PR_NUMBER" >> "$GITHUB_OUTPUT"
-            echo "source_link=Source PR: [$PR_NUMBER](https://github.com/${{ github.repository }}/pull/$PR_NUMBER)" >> "$GITHUB_OUTPUT"
-          else
-            echo "No PR number found in commit message, using commit link"
-            echo "pr_number=" >> "$GITHUB_OUTPUT" 
-            echo "pr_url=" >> "$GITHUB_OUTPUT"
-            echo "source_link=Source commit: [${{ github.sha }}](https://github.com/${{ github.repository }}/commit/${{ github.sha }})" >> "$GITHUB_OUTPUT"
+          echo "Finding last successful workflow run..."
+          LAST_SUCCESS_SHA=$(gh run list \
+            --workflow "${{ github.workflow }}" \
+            --branch "${{ github.ref_name }}" \
+            --status "success" \
+            --json "headSha" \
+            --jq '.[0].headSha // empty' \
+            -L 1)
+
+          RELEVANT_COMMITS=""
+          if [[ -n "$LAST_SUCCESS_SHA" ]]; then
+            echo "Last successful commit: $LAST_SUCCESS_SHA"
+            echo "Current commit: ${{ github.sha }}"
+
+            # Find all commits between the last success and now that touched the relevant files
+            # NOTE: The pathspecs here mirror the workflow's 'paths' trigger for precision
+            RELEVANT_COMMITS=$(git log --pretty=format:"- [%h](https://github.com/${{ github.repository }}/commit/%H) %s" $LAST_SUCCESS_SHA..${{ github.sha }} -- \
+              'packages/cli/src/public-api/**/*.css' \
+              'packages/cli/src/public-api/**/*.yaml' \
+              'packages/cli/src/public-api/**/*.yml')
           fi
 
+          if [[ -z "$RELEVANT_COMMITS" ]]; then
+            if [[ -z "$LAST_SUCCESS_SHA" ]]; then
+              echo "No previous successful run found. Using current commit as source."
+            else
+              echo "No commits touching source files found. Linking to trigger commit (likely a dependency update)."
+            fi
+            FULL_SHA="${{ github.sha }}"
+            SHORT_SHA="${FULL_SHA:0:7}"
+            SOURCE_LINK="Source commit: [$SHORT_SHA](https://github.com/${{ github.repository }}/commit/$FULL_SHA)"
+          else
+            echo "Found relevant source commits:"
+            echo "$RELEVANT_COMMITS"
+            # Build the string manually to avoid heredoc capturing leading whitespace from YAML
+            SOURCE_LINK="Source commit(s):"$'\n'"$RELEVANT_COMMITS"
+          fi
+
+          echo "source_link<<EOF" >> "$GITHUB_OUTPUT"
+          echo "$SOURCE_LINK" >> "$GITHUB_OUTPUT"
+          echo "EOF" >> "$GITHUB_OUTPUT"
+
       - name: Create PR in Docs Repo
         if: steps.verify_file.outputs.file_exists == 'true'
 
@@ -127,6 +156,6 @@ jobs:
             Automated update of the Public API OpenAPI YAML schema.
 
             This PR was generated by a GitHub Action in the [${{ github.repository }} repository](https://github.com/${{ github.repository }}).
-            ${{ steps.extract_pr.outputs.source_link }}
+            ${{ steps.find_source_commits.outputs.source_link }}
 
             Please review the changes and merge if appropriate.