feat: add Ruff for Python linting

.github/workflows/lint.yml

@@ -6,16 +6,22 @@ on:
       - 'static/**'
       - 'package.json'
       - 'biome.json'
+      - '*.py'
+      - 'pyproject.toml'
+      - 'uv.lock'
   push:
     branches:
       - main
     paths:
       - 'static/**'
       - 'package.json'
       - 'biome.json'
+      - '*.py'
+      - 'pyproject.toml'
+      - 'uv.lock'
 
 jobs:
-  lint:
+  lint-frontend:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
@@ -32,3 +38,24 @@ jobs:
 
       - name: Run Biome
         run: npm run lint
+
+  lint-python:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Setup Python
+        uses: actions/setup-python@v5
+        with:
+          python-version: '3.11'
+          cache: 'pip'
+
+      - name: Install uv
+        run: pip install uv
+
+      - name: Install dependencies
+        run: uv sync --dev
+
+      - name: Run Ruff
+        run: uv run ruff check .

AGENTS.md

@@ -79,13 +79,25 @@ pytest tests/test_linting.py::test_lint_area
 
 ### Linting/Formatting
 
-No automated linting is configured. If adding:
+Python linting with Ruff:
 
 ```bash
-# Recommended: ruff for linting + formatting
-uv add ruff
-ruff check .
-ruff format .
+# Install dependencies
+uv sync --dev
+
+# Run linting
+uv run ruff check .
+
+# Auto-fix issues
+uv run ruff check . --fix
+```
+
+Frontend linting with Biome (JavaScript/CSS):
+
+```bash
+npm install
+npm run lint
+npm run format
 ```
 
 ## Code Style Guidelines

app.py

@@ -1,16 +1,32 @@
-import os
-from flask import Flask, render_template, request, jsonify, session, redirect, url_for
-from flask_session import Session
-import requests
 import json
+import os
+import re
 from datetime import datetime, timedelta
-from geojson_rewind import rewind
 from urllib.parse import urlparse
-import re
+
+import pyproj
+import requests
+from flask import (
+    Flask,
+    jsonify,
+    redirect,
+    render_template,
+    request,
+    session,
+    url_for,
+)
+from geojson_rewind import rewind
 from shapely.geometry import shape
 from shapely.ops import transform
-import pyproj
-from linting import lint_area_dict, lint_cache, LINT_RULES, FIX_ACTIONS, fix_migrate_icon, fix_bump_verified
+
+from linting import (
+    FIX_ACTIONS,
+    LINT_RULES,
+    fix_bump_verified,
+    fix_migrate_icon,
+    lint_area_dict,
+    lint_cache,
+)
 
 app = Flask(__name__)
 app.config['SECRET_KEY'] = os.environ.get('SECRET_KEY', 'dev-secret-key-change-in-production')
@@ -1128,7 +1144,7 @@ def validate_url(value, allowed_values=None):
     try:
         result = urlparse(value)
         return all([result.scheme, result.netloc]), "Invalid URL format"
-    except:
+    except Exception:
         return False, "Invalid URL"
 
 

linting.py

@@ -6,13 +6,14 @@
 
 import fnmatch
 import re
-import requests
+from dataclasses import asdict, dataclass
 from datetime import datetime, timedelta
-from typing import Optional
-from dataclasses import dataclass, asdict
 from enum import Enum
-from shapely.geometry import shape, Point
+from typing import Optional
+
+import requests
 from shapely import STRtree
+from shapely.geometry import shape
 
 
 class Severity(Enum):
@@ -122,7 +123,7 @@ def check_icon_legacy_url(area: dict) -> Optional[LintResult]:
     if not re.match(expected_pattern, icon_url):
         return LintResult(
             rule=LINT_RULES['icon-legacy-url'],
-            message=f'Icon URL does not match expected format',
+            message='Icon URL does not match expected format',
             current_value=icon_url
         )
 

main.py

@@ -1,4 +1,5 @@
 import os
+
 from app import app
 
 if __name__ == "__main__":

pyproject.toml

@@ -16,3 +16,16 @@ dependencies = [
     "pyproj>=3.7.0",
     "gunicorn>=23.0.0",
 ]
+
+[dependency-groups]
+dev = [
+    "ruff>=0.15.2",
+]
+
+[tool.ruff]
+line-length = 80
+indent-width = 4
+
+[tool.ruff.lint]
+select = ["E", "F", "I"]
+ignore = ["E501"]