Smarter download

[Artoria2e5]

Right now the downloady part does a single request stream, so I have to deal with a 1.5 MB/s speed to Tencent mirror of all places. And there's no possibility for continuation, so it's not like I even dare to interrupt it.

This is a step backwards from axel. Bear with me, but maybe downloading large files is not what a general-purpose request library should do.

Now about solutions.

• Just call axel. Command line calls are not that evil.
• https://github.com/x0f5c3/manic is a layer over reqwest that implements a multithreaded download client. It's not as awesome as axel (no multi-server, no continue), but it will probably do.
• or what if we just hooked this thing up to libtorrent? It's got multi-server webseeds AND continue. You even get file integrity on block level. Big dependency, I know, but game studios are doing it too!