Added Ruff linting

pyproject.toml

@@ -0,0 +1,28 @@
+[tool.ruff]
+line-length = 120
+target-version = "py312"
+[tool.ruff.lint]
+select = [
+	"E", "F", # pycodestyle errors, pyflakes (unused imports/variables, undefined names)
+	"I", # import sorting (replaces isort)
+	"B", # bugbear: likely bugs
+	"ASYNC", # async mistakes
+	"RUF006", # un-referenced asyncio.create_task (tasks can be garbage-collected)
+]
+ignore = ["E501"]
+
+[tool.ruff.lint.isort]
+known-first-party = ["db_module", "metrics_server", "rabbitmq_handler", "secret_manager",
+					"simple_logger_handler", "uvicorn_logger_config", "validator"]
+
+[tool.ruff.format]
+indent-style = "tab"
+
+[tool.ruff.lint.flake8-bugbear]
+extend-immutable-calls = [
+	"fastapi.Depends",
+	"fastapi.Query",
+	"fastapi.Header",
+	"fastapi.Body",
+	"fastapi.Security",
+]

requirements-dev.txt

@@ -0,0 +1 @@
+ruff==0.17.0

src/main.py

@@ -1,23 +1,25 @@
-from fastapi import FastAPI, Depends, HTTPException, Request
+import asyncio
+import os
+import uuid
+from contextlib import asynccontextmanager
+from hashlib import sha256
+from typing import List, Optional
+
+import httpx
+import uvicorn
+from fastapi import Depends, FastAPI, HTTPException, Request
 from fastapi.responses import JSONResponse
 from fastapi.security.api_key import APIKeyHeader
-from starlette.exceptions import HTTPException as StarletteHTTPException
-from typing import Optional,List
 from pydantic import BaseModel
-from validator import is_valid_platform,is_valid_token,verify_api_key
-from secret_manager.fernet_encryption import encrypt_token
-from secret_manager import cleanup_secret_files, return_credentials
-from db_module import get_db, create_connection_pool, close_connection_pool, start_healthcheck_thread
-from simple_logger_handler import setup_logger, LOG_LEVEL
-import uuid
-from hashlib import sha256
-import uvicorn
-from contextlib import asynccontextmanager
+from starlette.exceptions import HTTPException as StarletteHTTPException
+
+from db_module import close_connection_pool, create_connection_pool, get_db, start_healthcheck_thread
 from metrics_server import REQUEST_COUNTER
-import asyncio
+from secret_manager import cleanup_secret_files, return_credentials
+from secret_manager.fernet_encryption import encrypt_token
+from simple_logger_handler import LOG_LEVEL, setup_logger
 from uvicorn_logger_config import LOGGING_CONFIG
-import httpx
-import os
+from validator import is_valid_platform, is_valid_token, verify_api_key
 
 logger = setup_logger(__name__)
 api_key_header = APIKeyHeader(name="X-API-Key")
@@ -168,7 +170,7 @@ def register_token(
 		cursor = db.cursor()
 		cursor.execute(
 			"SELECT * FROM device_tokens WHERE user_id=%s AND hashed_token=%s",
-			  (user_id,hashed_token))
+			(user_id,hashed_token))
 		existing = cursor.fetchone()
 		logger.debug(f"[FastAPI] Existing token fetched: {existing}")
 
@@ -178,8 +180,8 @@ def register_token(
 				UPDATE device_tokens
 				SET platform=%s, app_ver=%s, locale=%s, topics=%s, last_seen_at=NOW()
 				WHERE user_id=%s AND hashed_token=%s
-			""", (request_data.platform,
-		 		request_data.app_ver,
+			""",(request_data.platform,
+				request_data.app_ver,
 				request_data.locale,
 				request_data.topics,
 				user_id,
@@ -193,7 +195,7 @@ def register_token(
 				(token_id, user_id, platform, token, hashed_token, status, app_ver, locale, topics, created_at)
 				VALUES (%s,%s,%s,%s,%s,%s,%s,%s,%s,NOW())
 			""", (token_id,
-		 		user_id,
+				user_id,
 				request_data.platform,
 				secure_token,
 				hashed_token,
@@ -207,7 +209,7 @@ def register_token(
 		logger.info(f"[FastAPI] Success: Registering token for user_id={user_id}, platform={request_data.platform}")
 	except Exception as e:
 		logger.exception(f"[FastAPI] Failed to register token for user_id={user_id}: {e}")
-		raise HTTPException(status_code=500, detail=str(e))
+		raise HTTPException(status_code=500, detail=str(e)) from e
 
 	return {"status":"registered"}	
 
@@ -230,7 +232,7 @@ def unregister_token(
 			""", ('expired', hashed_token))
 	except Exception as e:
 		logger.exception(f"[FastAPI] Failed to unregister token for user_id={user_id}: {e}")
-		raise HTTPException(status_code=500, detail=str(e))
+		raise HTTPException(status_code=500, detail=str(e)) from e
 	logger.info(f"[FastAPI] Success: Unregistering token for user_id={user_id}, platform={request_data.platform}")
 	return {"status":"unregistered"}
 
@@ -248,10 +250,10 @@ async def pull_notifications(
 		data = PullResponse.model_validate(resp.json())
 	except httpx.HTTPStatusError as e:
 		logger.error(f"[FastAPI] Upstream returned {e.response.status_code} for user_id={user_id}")
-		raise HTTPException(status_code=502, detail="Backend-API-Internal unavailable")
+		raise HTTPException(status_code=502, detail="Backend-API-Internal unavailable") from e
 	except ValueError as e:
 		logger.error(f"[FastAPI] Backend-API-Internal call failed with ValueError for user_id={user_id}: {e!r}")
-		raise HTTPException(status_code=502, detail="Backend-API-Internal unavailable")
+		raise HTTPException(status_code=502, detail="Backend-API-Internal unavailable") from e
 
 	logger.info(f"[FastAPI] Returning {len(data.messages)} message(s) for user_id={user_id}, has_more={data.has_more}")
 	return data

src/metrics_server.py

@@ -1,5 +1,5 @@
 from fastapi import FastAPI, Response
-from prometheus_client import generate_latest, CONTENT_TYPE_LATEST, Counter
+from prometheus_client import CONTENT_TYPE_LATEST, Counter, generate_latest
 
 metrics_api = FastAPI(title="Metrics Server", description="Prometheus metrics endpoint")
 

src/validator.py

@@ -1,5 +1,7 @@
-from argon2 import PasswordHasher
 import re
+
+from argon2 import PasswordHasher
+
 from simple_logger_handler import setup_logger
 
 logger = setup_logger(__name__)