fix: resolve all 67 ruff lint errors

Fix import sorting, unused imports, line length violations, nested
if/with statements, missing raise-from chains, and try/except/pass
patterns across source and test files.

Author: ServerSideHannes

s3proxy/app.py

@@ -16,7 +16,6 @@
 from prometheus_client import CONTENT_TYPE_LATEST, generate_latest
 from structlog.stdlib import BoundLogger
 
-from . import metrics  # Ensure Prometheus collectors are registered at import time
 from .config import Settings
 from .errors import S3Error, get_s3_error_code
 from .handlers import S3ProxyHandler

s3proxy/client/verifier.py

@@ -64,7 +64,13 @@ def _parse_v4_credential(
         return creds, date_stamp, region, service, None
 
     def _compute_v4_signature(
-        self, canonical_request: str, amz_date: str, date_stamp: str, region: str, service: str, secret_key: str
+        self,
+        canonical_request: str,
+        amz_date: str,
+        date_stamp: str,
+        region: str,
+        service: str,
+        secret_key: str,
     ) -> str:
         """Compute V4 signature for a canonical request."""
         string_to_sign = self._build_string_to_sign(

s3proxy/concurrency.py

@@ -3,6 +3,7 @@
 from __future__ import annotations
 
 import asyncio
+import contextlib
 import ctypes
 import gc
 import os
@@ -111,10 +112,8 @@ async def release(self, bytes_reserved: int) -> None:
         gc.collect(2)
 
         if _malloc_release:
-            try:
+            with contextlib.suppress(OSError):
                 _malloc_release()
-            except OSError:
-                pass
 
         # Yield to allow OS memory reclaim
         await asyncio.sleep(0)

s3proxy/handlers/base.py

@@ -108,8 +108,8 @@ def _parse_range(self, header: str, size: int) -> tuple[int, int]:
             else:
                 parts = spec.split("-")
                 start, end = int(parts[0]), min(int(parts[1]), size - 1)
-        except (ValueError, IndexError):
-            raise S3Error.invalid_range("Invalid range header format")
+        except (ValueError, IndexError) as err:
+            raise S3Error.invalid_range("Invalid range header format") from err
         if start > end or start >= size:
             raise S3Error.invalid_range("Range not satisfiable")
         return start, end
@@ -122,8 +122,8 @@ def _parse_copy_source_range(
         range_str = range_header.replace("bytes=", "")
         try:
             start, end = map(int, range_str.split("-"))
-        except (ValueError, TypeError):
-            raise S3Error.invalid_range("Invalid copy source range format")
+        except (ValueError, TypeError) as err:
+            raise S3Error.invalid_range("Invalid copy source range format") from err
         if start > end or start >= total_size:
             raise S3Error.invalid_range("Range not satisfiable")
         return start, min(end, total_size - 1)

s3proxy/handlers/multipart/lifecycle.py

@@ -185,7 +185,9 @@ async def handle_complete_multipart_upload(
             )
 
             location = f"{self.settings.s3_endpoint}/{bucket}/{key}"
-            etag = hashlib.md5(str(state.total_plaintext_size).encode(), usedforsecurity=False).hexdigest()
+            etag = hashlib.md5(
+                str(state.total_plaintext_size).encode(), usedforsecurity=False
+            ).hexdigest()
 
             return Response(
                 content=xml_responses.complete_multipart(location, bucket, key, etag),

s3proxy/request_handler.py

@@ -13,14 +13,14 @@
 from structlog.stdlib import BoundLogger
 
 from . import concurrency, crypto
+from .errors import S3Error, raise_for_client_error, raise_for_exception
+from .handlers import S3ProxyHandler
 from .metrics import (
     REQUEST_COUNT,
     REQUEST_DURATION,
     REQUESTS_IN_FLIGHT,
     get_operation_name,
 )
-from .errors import S3Error, raise_for_client_error, raise_for_exception
-from .handlers import S3ProxyHandler
 from .routing import RequestDispatcher
 from .s3client import ParsedRequest, SigV4Verifier
 

s3proxy/state/__init__.py

@@ -36,9 +36,6 @@
 # Recovery
 from .recovery import reconstruct_upload_state_from_s3
 
-# Serialization utilities
-from .serialization import json_dumps, json_loads
-
 # Redis client
 from .redis import (
     close_redis,
@@ -47,6 +44,9 @@
     init_redis,
     is_using_redis,
 )
+
+# Serialization utilities
+from .serialization import json_dumps, json_loads
 from .storage import MemoryStateStore, RedisStateStore, StateStore
 
 __all__ = [

s3proxy/state/storage.py

@@ -141,7 +141,11 @@ async def get_and_delete(self, key: str, _retries: int = 0) -> bytes | None:
 
             except redis.WatchError:
                 if _retries >= MAX_WATCH_RETRIES:
-                    logger.error("REDIS_WATCH_RETRIES_EXHAUSTED", key=key, operation="get_and_delete")
+                    logger.error(
+                        "REDIS_WATCH_RETRIES_EXHAUSTED",
+                        key=key,
+                        operation="get_and_delete",
+                    )
                     raise
                 logger.debug("REDIS_WATCH_RETRY", key=key, attempt=_retries + 1)
                 return await self.get_and_delete(key, _retries=_retries + 1)

tests/conftest.py

@@ -14,10 +14,10 @@
 os.environ.setdefault("S3PROXY_ENCRYPT_KEY", "test-encryption-key-for-pytest")
 os.environ.setdefault("S3PROXY_HOST", "http://localhost:9000")
 
-from s3proxy.state import redis as state_redis
 from s3proxy.config import Settings
-from s3proxy.state import MultipartStateManager
 from s3proxy.s3client import S3Client, S3Credentials
+from s3proxy.state import MultipartStateManager
+from s3proxy.state import redis as state_redis
 
 # ============================================================================
 # Redis Fixtures

tests/ha/test_ha_redis_e2e.py

@@ -21,8 +21,6 @@
 import httpx
 import pytest
 
-from s3proxy.config import Settings
-
 
 def is_docker_available():
     """Check if Docker is available and running."""