Run Ruff only on selected changed Python files in PRs (#71)

.github/workflows/ruff-check.yml

@@ -1,38 +1,64 @@
-name: Ruff check for python code
+name: Ruff check on changed files only
 
 on:
-    push: 
-        branches: 
-            - main
-        paths: 
-            - 'api-server/**'
-            - 'state-manager/**'
-    pull_request:
-        branches:
-            - main
-        paths:
-            - 'api-server/**'
-            - 'state-manager/**'
-    workflow_dispatch:
+  push:
+    branches: [main]
+  pull_request:
+    branches: [main]
+  workflow_dispatch:
 
 permissions:
-    contents: read
-    id-token: write
-    pages: write
+  contents: read
 
 jobs:
-    check:
-        runs-on: ubuntu-latest
-        steps:
-            - uses: actions/checkout@v4
-            - uses: actions/setup-python@v5
-              with:
-                python-version: '3.12'
-            - name: Ruff Check
-              uses: astral-sh/ruff-action@v3
-              with:
-                src: './api-server'
-            - name: Ruff Check
-              uses: astral-sh/ruff-action@v3
-              with:
-                src: './state-manager'
+  ruff-changed-files:
+    runs-on: ubuntu-latest
+
+    steps:
+      # 1. Checkout entire history for accurate diffs
+      - name: Checkout code
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+
+      # 2. Set up Python for Ruff
+      - name: Set up Python
+        uses: actions/setup-python@v5
+        with:
+          python-version: '3.12'
+
+      # 3. Determine changed Python files in api-server/ and state-manager/
+      - name: Get changed Python files
+        id: changed-files
+        run: |
+          if [[ "${{ github.event_name }}" == "pull_request" ]]; then
+            BASE_SHA=${{ github.event.pull_request.base.sha }}
+            HEAD_SHA=${{ github.sha }}
+          else
+            BASE_SHA=${{ github.event.before }}
+            HEAD_SHA=${{ github.event.after }}
+          fi
+
+          # List all changed .py files in target directories
+          FILES=$(git diff --name-only --diff-filter=ACMRT $BASE_SHA $HEAD_SHA \
+                  | grep -E '^(api-server|state-manager)/.*\.py$' || true)
+
+          echo "files=$FILES" >> "$GITHUB_OUTPUT"
+
+
+
+
+      # 4. Install and Run Ruff on changed files, if any
+      - name: Run Ruff on changed files
+        if: steps.changed-files.outputs.files != ''
+        run: |
+          pip install ruff
+          echo "Linting the following Python files:"
+          echo "${{ steps.changed-files.outputs.files }}"
+          ruff check ${{ steps.changed-files.outputs.files }}
+
+      # 5. Skip Ruff when no relevant files changed
+      - name: Skip Ruff if no files changed
+        if: steps.changed-files.outputs.files == ''
+        run: |
+          echo "No Python files changed in api-server/ or state-manager/. Skipping Ruff."