python - 如何在twisted中创建部分下载？

Question

如何创建多个异步部分下载的 HTTPDownloader 实例？所有下载完成后它会自动组装文件吗？

Answer 1

您必须使用 Range HTTP header :

Range. Request only part of an entity. Bytes are numbered from 0. Range: bytes=500-999

即。如果您想分 4 部分下载 1000 个文件，您将开始 4 次下载:

1. 0-2499
2. 2500-4999
3. 5000-7499
4. 7500-9999

然后只需连接响应中的数据即可。

要检查文件大小，您可以使用 HEAD 方法:

HEAD Asks for the response identical to the one that would correspond to a GET request, but without the response body. This is useful for retrieving meta-information written in response headers, without having to transport the entire content.