feat: enhance error logging and upstream response tracking for provider failures

src/api/handlers/base/chat_handler_base.py

@@ -639,6 +639,8 @@ class ChatHandlerBase(BaseMessageHandler, ABC):
 
             logger.info(f"  [{self.request_id}] 发送非流式请求: Provider={provider.name}, "
                 f"模型={model} -> {mapped_model or '无映射'}")
+            logger.debug(f"  [{self.request_id}] 请求URL: {url}")
+            logger.debug(f"  [{self.request_id}] 请求体stream字段: {provider_payload.get('stream', 'N/A')}")
 
             # 创建 HTTP 客户端（支持代理配置）
             from src.clients.http_client import HTTPClientPool
@@ -662,10 +664,32 @@ class ChatHandlerBase(BaseMessageHandler, ABC):
                         response_headers=response_headers,
                     )
                 elif resp.status_code >= 500:
-                    raise ProviderNotAvailableException(f"提供商服务不可用: {provider.name}")
-                elif resp.status_code != 200:
+                    # 记录响应体以便调试
+                    error_body = ""
+                    try:
+                        error_body = resp.text[:1000]
+                        logger.error(f"  [{self.request_id}] 上游返回5xx错误: status={resp.status_code}, body={error_body[:500]}")
+                    except Exception:
+                        pass
                     raise ProviderNotAvailableException(
-                        f"提供商返回错误: {provider.name}, 状态: {resp.status_code}"
+                        f"提供商服务不可用: {provider.name}",
+                        provider_name=str(provider.name),
+                        upstream_status=resp.status_code,
+                        upstream_response=error_body,
+                    )
+                elif resp.status_code != 200:
+                    # 记录非200响应以便调试
+                    error_body = ""
+                    try:
+                        error_body = resp.text[:1000]
+                        logger.warning(f"  [{self.request_id}] 上游返回非200: status={resp.status_code}, body={error_body[:500]}")
+                    except Exception:
+                        pass
+                    raise ProviderNotAvailableException(
+                        f"提供商返回错误: {provider.name}, 状态: {resp.status_code}",
+                        provider_name=str(provider.name),
+                        upstream_status=resp.status_code,
+                        upstream_response=error_body,
                     )
 
                 response_json = resp.json()

src/core/exceptions.py

@@ -188,12 +188,16 @@ class ProviderNotAvailableException(ProviderException):
         message: str,
         provider_name: Optional[str] = None,
         request_metadata: Optional[Any] = None,
+        upstream_status: Optional[int] = None,
+        upstream_response: Optional[str] = None,
     ):
         super().__init__(
             message=message,
             provider_name=provider_name,
             request_metadata=request_metadata,
         )
+        self.upstream_status = upstream_status
+        self.upstream_response = upstream_response
 
 
 class ProviderTimeoutException(ProviderException):

src/main.py

@@ -4,13 +4,10 @@
 """
 
 from contextlib import asynccontextmanager
-from pathlib import Path
 
 import uvicorn
-from fastapi import FastAPI, HTTPException, Request
+from fastapi import FastAPI, HTTPException
 from fastapi.middleware.cors import CORSMiddleware
-from fastapi.responses import FileResponse
-from fastapi.staticfiles import StaticFiles
 
 from src.api.admin import router as admin_router
 from src.api.announcements import router as announcement_router
@@ -299,33 +296,6 @@ app.include_router(dashboard_router)  # 仪表盘端点
 app.include_router(public_router)  # 公开API端点（用户可查看提供商和模型）
 app.include_router(monitoring_router)  # 监控端点
 
-# 静态文件服务（前端构建产物）
-# 检查前端构建目录是否存在
-frontend_dist = Path(__file__).parent.parent / "frontend" / "dist"
-if frontend_dist.exists():
-    # 挂载静态资源目录
-    app.mount("/assets", StaticFiles(directory=str(frontend_dist / "assets")), name="assets")
-
-    # SPA catch-all路由 - 必须放在最后
-    @app.get("/{full_path:path}")
-    async def serve_spa(request: Request, full_path: str):
-        """
-        处理所有未匹配的GET请求，返回index.html供前端路由处理
-        仅对非API路径生效
-        """
-        # 如果是API路径，不处理
-        if full_path in {"api", "v1"} or full_path.startswith(("api/", "v1/")):
-            raise HTTPException(status_code=404, detail="Not Found")
-
-        # 返回index.html，让前端路由处理
-        index_file = frontend_dist / "index.html"
-        if index_file.exists():
-            return FileResponse(str(index_file))
-        else:
-            raise HTTPException(status_code=404, detail="Frontend not built")
-
-else:
-    logger.warning("前端构建目录不存在，前端路由将无法使用")
 
 
 def main():

src/services/orchestration/fallback_orchestrator.py

@@ -427,6 +427,9 @@ class FallbackOrchestrator:
             )
             # str(cause) 可能为空（如 httpx 超时异常），使用 repr() 作为备用
             error_msg = str(cause) or repr(cause)
+            # 如果是 ProviderNotAvailableException，附加上游响应
+            if hasattr(cause, "upstream_response") and cause.upstream_response:
+                error_msg = f"{error_msg} | 上游响应: {cause.upstream_response[:500]}"
             RequestCandidateService.mark_candidate_failed(
                 db=self.db,
                 candidate_id=candidate_record_id,
@@ -439,6 +442,9 @@ class FallbackOrchestrator:
 
         # 未知错误：记录失败并抛出
         error_msg = str(cause) or repr(cause)
+        # 如果是 ProviderNotAvailableException，附加上游响应
+        if hasattr(cause, "upstream_response") and cause.upstream_response:
+            error_msg = f"{error_msg} | 上游响应: {cause.upstream_response[:500]}"
         RequestCandidateService.mark_candidate_failed(
             db=self.db,
             candidate_id=candidate_record_id,

src/services/request/result.py

@@ -289,11 +289,17 @@ class RequestResult:
             status_code = 500
             error_type = "internal_error"
 
+        # 构建错误消息，包含上游响应信息
+        error_message = str(exception)
+        if isinstance(exception, ProviderNotAvailableException):
+            if exception.upstream_response:
+                error_message = f"{error_message} | 上游响应: {exception.upstream_response[:500]}"
+
         return cls(
             status=RequestStatus.FAILED,
             metadata=metadata,
             status_code=status_code,
-            error_message=str(exception),
+            error_message=error_message,
             error_type=error_type,
             response_time_ms=response_time_ms,
             is_stream=is_stream,