chore: 后端 agent 和 users 模块代码更新优化

backend/src/v1/agent/router.py

@@ -3,7 +3,9 @@ from __future__ import annotations
 from collections.abc import AsyncIterator
 import asyncio
 from datetime import date
+import os
 import re
+import tempfile
 import time
 from typing import Annotated, Union
 
@@ -29,6 +31,21 @@ _LAST_EVENT_ID_RE = re.compile(r"^\d+-\d+$")
 _RUNS_PER_MINUTE = 30
 _MAX_SSE_CONNECTIONS_PER_USER = 3
 _SSE_SLOT_TTL_SECONDS = 15 * 60
+_MAX_TRANSCRIBE_AUDIO_BYTES = 10 * 1024 * 1024
+_TRANSCRIBE_READ_CHUNK_BYTES = 1024 * 1024
+_MULTIPART_OVERHEAD_BYTES = 64 * 1024
+_WAV_HEADER_MIN_BYTES = 12
+_ALLOWED_AUDIO_CONTENT_TYPES = {
+    "audio/wav",
+    "audio/x-wav",
+    "audio/wave",
+}
+
+
+def _looks_like_wav_header(header: bytes) -> bool:
+    if len(header) < _WAV_HEADER_MIN_BYTES:
+        return False
+    return header[0:4] == b"RIFF" and header[8:12] == b"WAVE"
 
 
 async def _allow_run_request(*, user_id: str) -> bool:
@@ -220,15 +237,52 @@ async def get_user_history_snapshot(
 )
 async def transcribe(
     audio: UploadFile,
+    request: Request,
     current_user: Annotated[CurrentUser, Depends(get_current_user)],
 ) -> Union[AsrTranscribeResponse, JSONResponse]:
+    del current_user
+    temp_path: str | None = None
     try:
-        audio_data = await audio.read()
-        if not audio_data:
-            raise ValueError("Empty audio file")
+        if audio.content_type not in _ALLOWED_AUDIO_CONTENT_TYPES:
+            raise ValueError("Unsupported audio format")
 
-        transcript = await asr_service.transcribe(
-            audio_data, audio.filename or "unknown"
+        content_length = request.headers.get("content-length")
+        if content_length is not None:
+            try:
+                declared_length = int(content_length)
+            except ValueError:
+                declared_length = None
+            if (
+                declared_length is not None
+                and declared_length
+                > _MAX_TRANSCRIBE_AUDIO_BYTES + _MULTIPART_OVERHEAD_BYTES
+            ):
+                raise ValueError("Audio file too large")
+
+        with tempfile.NamedTemporaryFile(delete=False, suffix=".wav") as tmp_file:
+            temp_path = tmp_file.name
+
+            total_bytes = 0
+            header = bytearray()
+            while True:
+                chunk = await audio.read(_TRANSCRIBE_READ_CHUNK_BYTES)
+                if not chunk:
+                    break
+                total_bytes += len(chunk)
+                if total_bytes > _MAX_TRANSCRIBE_AUDIO_BYTES:
+                    raise ValueError("Audio file too large")
+                if len(header) < _WAV_HEADER_MIN_BYTES:
+                    required = _WAV_HEADER_MIN_BYTES - len(header)
+                    header.extend(chunk[:required])
+                tmp_file.write(chunk)
+
+        if total_bytes == 0:
+            raise ValueError("Empty audio file")
+        if not _looks_like_wav_header(bytes(header)):
+            raise ValueError("Unsupported audio format")
+
+        transcript = await asr_service.transcribe_file(
+            temp_path, audio.filename or "unknown"
         )
 
         return AsrTranscribeResponse(transcript=transcript)
@@ -238,8 +292,12 @@ async def transcribe(
             status_code=status.HTTP_400_BAD_REQUEST,
             content={"detail": str(exc)},
         )
-    except RuntimeError as exc:
+    except RuntimeError:
         return JSONResponse(
-            status_code=status.HTTP_500_INTERNAL_SERVER_ERROR,
-            content={"detail": str(exc)},
+            status_code=status.HTTP_502_BAD_GATEWAY,
+            content={"detail": "ASR service unavailable"},
         )
+    finally:
+        await audio.close()
+        if temp_path and os.path.exists(temp_path):
+            os.unlink(temp_path)