优化流式响应日志功能

src/api/middleware/logging_middleware.py

@@ -4,141 +4,218 @@ Logging middleware for request/response debugging.
 import json
 import logging
 import time
-from typing import Callable
-from fastapi import Request, Response
-from starlette.middleware.base import BaseHTTPMiddleware
-from starlette.responses import StreamingResponse
+from typing import Callable, Awaitable
+
+from starlette.types import ASGIApp, Scope, Receive, Send, Message
+from starlette.requests import Request
+from starlette.datastructures import Headers
 
 from core.config import get_settings
 
 logger = logging.getLogger(__name__)
 
 
-class LoggingMiddleware(BaseHTTPMiddleware):
+class LoggingMiddleware:
     """
-    Middleware to log detailed request and response information.
+    Pure ASGI middleware to log detailed request and response information.
     Activated when LOG_REQUESTS or LOG_RESPONSES is enabled.
+
+    Uses pure ASGI interface to avoid compatibility issues with streaming responses.
     """
 
-    async def dispatch(self, request: Request, call_next: Callable) -> Response:
-        """Process request and log details."""
-        settings = get_settings()
+    def __init__(self, app: ASGIApp):
+        self.app = app
 
-        # Generate request ID for tracking
+    async def __call__(self, scope: Scope, receive: Receive, send: Send) -> None:
+        """Process ASGI request."""
+        if scope["type"] != "http":
+            # Only handle HTTP requests
+            await self.app(scope, receive, send)
+            return
+
+        settings = get_settings()
+        if not (settings.log_requests or settings.log_responses or settings.debug):
+            # Logging disabled, pass through
+            await self.app(scope, receive, send)
+            return
+
+        # Generate request ID
         request_id = f"req_{int(time.time() * 1000)}"
 
-        # Log request details
+        # Cache request body for logging
+        body_cache = None
+        body_received = False
+
+        async def receive_wrapper() -> Message:
+            """Wrap receive to cache request body."""
+            nonlocal body_cache, body_received
+            message = await receive()
+
+            if message["type"] == "http.request" and not body_received:
+                body_received = True
+                body_cache = message.get("body", b"")
+
+                # Log request after receiving body
                 if settings.log_requests or settings.debug:
-            await self._log_request(request, request_id)
+                    await self._log_request_with_body(scope, body_cache, request_id)
 
-        # Record start time
+            return message
+
+        # Track response
         start_time = time.time()
+        response_started = False
+        status_code = None
+        response_headers = None
+        is_streaming = False
+        response_body_chunks = []  # Accumulate response body chunks
 
-        # Process request
-        response = await call_next(request)
+        async def send_wrapper(message: Message) -> None:
+            """Wrap send to capture response details."""
+            nonlocal response_started, status_code, response_headers, is_streaming, response_body_chunks
 
-        # Calculate processing time
+            if message["type"] == "http.response.start":
+                response_started = True
+                status_code = message["status"]
+                response_headers = Headers(raw=message["headers"])
+
+                # Check if streaming by content-type
+                content_type = response_headers.get("content-type", "")
+                is_streaming = any(
+                    st in content_type
+                    for st in ["text/event-stream", "application/x-ndjson", "application/stream+json"]
+                )
+
+                # Log response start (for streaming, initial log)
+                if (settings.log_responses or settings.debug) and is_streaming and not settings.log_streaming:
+                    # Only log headers if LOG_STREAMING is disabled
                     process_time = time.time() - start_time
+                    logger.debug("=" * 80)
+                    logger.debug(f"[{request_id}] 📤 OUTGOING RESPONSE (Streaming)")
+                    logger.debug("=" * 80)
+                    logger.debug(f"Status Code: {status_code}")
+                    logger.debug(f"Processing Time: {process_time:.3f}s")
+                    logger.debug(f"Content-Type: {content_type}")
+                    logger.debug("Response Body: [Streaming - not logged (set LOG_STREAMING=true to enable)]")
+                    logger.debug("=" * 80)
 
-        # Log response details (only for non-streaming responses)
-        if (settings.log_responses or settings.debug) and not isinstance(response, StreamingResponse):
-            await self._log_response(response, request_id, process_time)
-        elif isinstance(response, StreamingResponse):
-            logger.debug(f"[{request_id}] Response: Streaming response (not logged)")
+            elif message["type"] == "http.response.body":
+                # Accumulate body chunks if logging streaming content
+                if is_streaming and settings.log_streaming:
+                    body_chunk = message.get("body", b"")
+                    if body_chunk:
+                        response_body_chunks.append(body_chunk)
 
-        return response
+                # Check if this is the last chunk
+                more_body = message.get("more_body", False)
+                if not more_body and is_streaming and settings.log_streaming and response_body_chunks:
+                    # Log complete streaming response
+                    process_time = time.time() - start_time
+                    full_body = b"".join(response_body_chunks)
+                    await self._log_streaming_response(
+                        request_id, status_code, response_headers, full_body, process_time
+                    )
 
-    async def _log_request(self, request: Request, request_id: str):
-        """Log detailed request information."""
+            await send(message)
+
+        # Call app with wrapped receive/send
+        await self.app(scope, receive_wrapper, send_wrapper)
+
+    async def _log_request_with_body(self, scope: Scope, body: bytes, request_id: str):
+        """Log detailed request information with cached body."""
         try:
+            # Extract request info from scope
+            method = scope.get("method", "")
+            path = scope.get("path", "")
+            query_string = scope.get("query_string", b"").decode()
+
             # Basic request info
             logger.debug("=" * 80)
             logger.debug(f"[{request_id}] 📨 INCOMING REQUEST")
             logger.debug("=" * 80)
-            logger.debug(f"Method: {request.method}")
-            logger.debug(f"URL: {request.url.path}")
-            logger.debug(f"Query Params: {dict(request.query_params)}")
+            logger.debug(f"Method: {method}")
+            logger.debug(f"URL: {path}")
+            if query_string:
+                logger.debug(f"Query String: {query_string}")
 
             # Headers (filter sensitive data)
-            headers = dict(request.headers)
+            headers = {}
+            for name, value in scope.get("headers", []):
+                name_str = name.decode("latin1")
+                value_str = value.decode("latin1")
+                headers[name_str] = value_str
+
             if "authorization" in headers:
                 headers["authorization"] = "Bearer ***"
             logger.debug(f"Headers: {json.dumps(headers, indent=2)}")
 
             # Request body
-            if request.method in ["POST", "PUT", "PATCH"]:
-                body = await self._read_body(request)
-                if body:
+            if method in ["POST", "PUT", "PATCH"] and body:
                 try:
                     # Try to parse and pretty-print JSON
-                        body_json = json.loads(body)
+                    body_json = json.loads(body.decode())
                     logger.debug(f"Request Body:\n{json.dumps(body_json, indent=2, ensure_ascii=False)}")
-                    except json.JSONDecodeError:
+                except (json.JSONDecodeError, UnicodeDecodeError):
                     # Log raw body if not JSON
-                        logger.debug(f"Request Body (raw): {body[:1000]}...")  # Limit to 1000 chars
+                    try:
+                        logger.debug(f"Request Body (raw): {body.decode()[:1000]}...")
+                    except:
+                        logger.debug(f"Request Body (binary): {len(body)} bytes")
 
             logger.debug("=" * 80)
 
         except Exception as e:
             logger.error(f"Error logging request: {e}")
 
-    async def _log_response(self, response: Response, request_id: str, process_time: float):
-        """Log detailed response information."""
+    async def _log_streaming_response(
+        self, request_id: str, status_code: int, headers: Headers, body: bytes, process_time: float
+    ):
+        """Log streaming response with full content."""
         try:
             logger.debug("=" * 80)
-            logger.debug(f"[{request_id}] 📤 OUTGOING RESPONSE")
+            logger.debug(f"[{request_id}] 📤 OUTGOING RESPONSE (Streaming - Complete)")
             logger.debug("=" * 80)
-            logger.debug(f"Status Code: {response.status_code}")
+            logger.debug(f"Status Code: {status_code}")
             logger.debug(f"Processing Time: {process_time:.3f}s")
+            logger.debug(f"Content-Type: {headers.get('content-type', 'N/A')}")
+            logger.debug(f"Total Size: {len(body)} bytes")
 
-            # Headers
-            headers = dict(response.headers)
-            logger.debug(f"Headers: {json.dumps(headers, indent=2)}")
+            # Parse and log SSE events
+            try:
+                body_str = body.decode("utf-8")
+                # Split by SSE event boundaries
+                events = [e.strip() for e in body_str.split("\n\n") if e.strip()]
+                logger.debug(f"SSE Events Count: {len(events)}")
 
-            # Response body
-            body = b""
-            async for chunk in response.body_iterator:
-                body += chunk
-
-            # Recreate response body iterator
-            response.body_iterator = self._create_body_iterator(body)
-
-            if body:
+                # Log first few events (limit to avoid huge logs)
+                max_events_to_log = 10
+                logger.debug("Response Body (SSE Events):")
+                for i, event in enumerate(events[:max_events_to_log]):
+                    if event.startswith("data: "):
+                        data_content = event[6:]  # Remove "data: " prefix
+                        if data_content == "[DONE]":
+                            logger.debug(f"  Event {i+1}: [DONE]")
+                        else:
                             try:
                                 # Try to parse and pretty-print JSON
-                    body_json = json.loads(body.decode())
-                    logger.debug(f"Response Body:\n{json.dumps(body_json, indent=2, ensure_ascii=False)}")
-                except (json.JSONDecodeError, UnicodeDecodeError):
-                    # Log raw body if not JSON
-                    logger.debug(f"Response Body (raw): {body[:1000]}...")  # Limit to 1000 chars
+                                event_json = json.loads(data_content)
+                                logger.debug(f"  Event {i+1}:")
+                                logger.debug(f"    {json.dumps(event_json, ensure_ascii=False)}")
+                            except json.JSONDecodeError:
+                                logger.debug(f"  Event {i+1}: {data_content[:200]}...")
+                    else:
+                        logger.debug(f"  Event {i+1}: {event[:200]}...")
+
+                if len(events) > max_events_to_log:
+                    logger.debug(f"  ... and {len(events) - max_events_to_log} more events")
+
+            except (UnicodeDecodeError, Exception) as e:
+                logger.debug(f"Response Body (raw): {body[:1000]}...")
+                logger.debug(f"(Could not parse SSE events: {e})")
 
             logger.debug("=" * 80)
 
         except Exception as e:
-            logger.error(f"Error logging response: {e}")
-
-    async def _read_body(self, request: Request) -> str:
-        """Read request body without consuming it."""
-        try:
-            body = await request.body()
-
-            # Create new receive callable to preserve body for downstream handlers
-            async def receive():
-                return {"type": "http.request", "body": body}
-
-            # Replace request's receive
-            request._receive = receive
-
-            return body.decode()
-        except Exception as e:
-            logger.error(f"Error reading request body: {e}")
-            return ""
-
-    def _create_body_iterator(self, body: bytes):
-        """Create an async iterator for response body."""
-        async def iterator():
-            yield body
-        return iterator()
+            logger.error(f"Error logging streaming response: {e}")
 
 
 def setup_logging_middleware(app):
@@ -148,9 +225,13 @@ def setup_logging_middleware(app):
     """
     settings = get_settings()
     if settings.log_requests or settings.log_responses or settings.debug:
+        # Add pure ASGI middleware
         app.add_middleware(LoggingMiddleware)
+
         logger.info("🔍 Request/Response logging middleware enabled")
         if settings.log_requests or settings.debug:
             logger.info("  - Request logging: ON")
         if settings.log_responses or settings.debug:
             logger.info("  - Response logging: ON")
+        if settings.log_streaming:
+            logger.info("  - Streaming content logging: ON (⚠️ increases memory usage)")

src/core/config.py

@@ -58,6 +58,7 @@ class Settings(BaseSettings):
     log_level: str = "INFO"
     log_requests: bool = False
     log_responses: bool = False
+    log_streaming: bool = False  # Log streaming response content (may increase memory usage)
     log_file: Optional[str] = None
     log_file_max_size: int = 10  # MB
     log_file_backup_count: int = 5