Initial public release

backend/infrastructure/file_utils.py

@@ -0,0 +1,105 @@
+import asyncio
+import logging
+import threading
+from pathlib import Path
+from typing import Any
+
+import aiofiles
+import aiofiles.os
+import msgspec
+
+logger = logging.getLogger(__name__)
+
+_file_locks: dict[str, threading.Lock] = {}
+_locks_lock = threading.Lock()
+_async_locks: dict[str, asyncio.Lock] = {}
+
+
+def _get_file_lock(file_path: Path) -> threading.Lock:
+    path_str = str(file_path.resolve())
+    with _locks_lock:
+        if path_str not in _file_locks:
+            _file_locks[path_str] = threading.Lock()
+        return _file_locks[path_str]
+
+
+def _get_async_lock(file_path: Path) -> asyncio.Lock:
+    path_str = str(file_path.resolve())
+    if path_str not in _async_locks:
+        _async_locks[path_str] = asyncio.Lock()
+    return _async_locks[path_str]
+
+
+def atomic_write_json(file_path: Path, data: Any, indent: int = 2) -> None:
+    lock = _get_file_lock(file_path)
+    
+    with lock:
+        file_path.parent.mkdir(parents=True, exist_ok=True)
+        tmp_path = file_path.with_suffix(file_path.suffix + '.tmp')
+        
+        try:
+            _ = indent
+            with open(tmp_path, 'wb') as f:
+                f.write(msgspec.json.encode(data))
+                f.flush()
+            
+            tmp_path.replace(file_path)
+            logger.debug(f"Atomically wrote JSON to {file_path}")
+            
+        except Exception as e:
+            if tmp_path.exists():
+                try:
+                    tmp_path.unlink()
+                except OSError as cleanup_error:
+                    logger.warning("Couldn't remove temp file %s: %s", tmp_path, cleanup_error)
+            logger.error(f"Failed to write JSON to {file_path}: {e}")
+            raise
+
+
+async def atomic_write_json_async(file_path: Path, data: Any, indent: int = 2) -> None:
+    lock = _get_async_lock(file_path)
+    
+    async with lock:
+        await aiofiles.os.makedirs(file_path.parent, exist_ok=True)
+        tmp_path = file_path.with_suffix(file_path.suffix + '.tmp')
+        
+        try:
+            _ = indent
+            content = msgspec.json.encode(data)
+            async with aiofiles.open(tmp_path, 'wb') as f:
+                await f.write(content)
+            
+            await asyncio.to_thread(tmp_path.replace, file_path)
+            logger.debug(f"Atomically wrote JSON to {file_path}")
+            
+        except Exception as e:
+            try:
+                if tmp_path.exists():
+                    await aiofiles.os.remove(tmp_path)
+            except OSError as cleanup_error:
+                logger.warning("Couldn't remove temp file %s: %s", tmp_path, cleanup_error)
+            logger.error(f"Failed to write JSON to {file_path}: {e}")
+            raise
+
+
+def read_json(file_path: Path, default: Any = None) -> Any:
+    lock = _get_file_lock(file_path)
+    
+    with lock:
+        if not file_path.exists():
+            return default
+        
+        with open(file_path, 'rb') as f:
+            return msgspec.json.decode(f.read())
+
+
+async def read_json_async(file_path: Path, default: Any = None) -> Any:
+    lock = _get_async_lock(file_path)
+    
+    async with lock:
+        if not file_path.exists():
+            return default
+        
+        async with aiofiles.open(file_path, 'rb') as f:
+            content = await f.read()
+            return msgspec.json.decode(content)