Class OpenDALFileStorage

core/storage.py:862–1010

class OpenDALFileStorage(FileStorageInterface):
    def __init__(self):
        try:
            import opendal
        except ImportError:
            raise ImportError('请先安装 `opendal`, 例如: "pip install opendal"')
        self.service = settings.opendal_scheme
        service_settings = {}
        for key, value in settings.items():
            if key.startswith("opendal_" + self.service):
                setting_name = key.split("_", 2)[2]
                service_settings[setting_name] = value
        self.operator = opendal.AsyncOperator(
            settings.opendal_scheme, **service_settings
        )

    async def save_file(self, file: UploadFile, save_path: str):
        # 使用 asyncio.to_thread 避免阻塞事件循环
        content = await asyncio.to_thread(file.file.read)
        await self.operator.write(save_path, content)

    async def delete_file(self, file_code: FileCodes):
        await self.operator.delete(await file_code.get_file_path())

    async def get_file_url(self, file_code: FileCodes):
        return await get_file_url(file_code.code)

    async def get_file_response(self, file_code: FileCodes):
        try:
            filename = file_code.prefix + file_code.suffix
            content_length = None  # 初始化为 None，表示未知大小
            
            # 尝试获取文件大小
            try:
                stat_result = await self.operator.stat(await file_code.get_file_path())
                if hasattr(stat_result, 'content_length') and stat_result.content_length:
                    content_length = stat_result.content_length
                elif hasattr(stat_result, 'size') and stat_result.size:
                    content_length = stat_result.size
            except Exception:
                # 如果获取大小失败，则不提供 Content-Length
                pass
            
            # 尝试使用流式读取器
            try:
                # OpenDAL 可能提供 reader 方法返回一个异步读取器
                reader = await self.operator.reader(await file_code.get_file_path())
            except AttributeError:
                # 如果 reader 方法不存在，回退到全量读取（兼容旧版本）
                content = await self.operator.read(await file_code.get_file_path())
                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 Response(
                    content, headers=headers, media_type="application/octet-stream"