Method get_file_response

core/storage.py:1144–1195

获取文件响应（代理模式）

(self, file_code: FileCodes)

        return await get_file_url(file_code.code)

    async def get_file_response(self, file_code: FileCodes):
        """获取文件响应（代理模式）"""
        try:
            filename = file_code.prefix + file_code.suffix
            url = self._build_url(await file_code.get_file_path())
            content_length = None  # 初始化为 None，表示未知大小
            
            # 创建ClientSession并复用（包含认证头）
            session = aiohttp.ClientSession(headers={
                "Authorization": f"Basic {base64.b64encode(f'{settings.webdav_username}:{settings.webdav_password}'.encode()).decode()}"
            })
            
            # 尝试发送HEAD请求获取Content-Length
            try:
                async with session.head(url) as resp:
                    if resp.status == 200 and 'Content-Length' in resp.headers:
                        content_length = int(resp.headers['Content-Length'])
            except Exception:
                # 如果HEAD请求失败，则不提供 Content-Length
                pass
            
            async def stream_generator():
                try:
                    async with session.get(url) as resp:
                        if resp.status != 200:
                            raise HTTPException(
                                status_code=resp.status,
                                detail=f"文件获取失败{resp.status}: {await resp.text()}",
                            )
                        chunk_size = 65536
                        while True:
                            chunk = await resp.content.read(chunk_size)
                            if not chunk:
                                break
                            yield chunk
                finally:
                    await session.close()
            
            encoded_filename = quote(filename, safe='')
            headers = {
                "Content-Disposition": f"attachment; filename*=UTF-8''{encoded_filename}"
            }
            if content_length is not None:
                headers["Content-Length"] = str(content_length)
            return StreamingResponse(
                stream_generator(),
                media_type="application/octet-stream",
                headers=headers
            )
        except aiohttp.ClientError as e:
            raise HTTPException(
                status_code=503, detail=f"WebDAV连接异常: {str(e)}")

    async def save_chunk(self, upload_id: str, chunk_index: int, chunk_data: bytes, chunk_hash: str, save_path: str):
        """保存分片到 WebDAV"""