Missing request timeouts in web browser

[lidel]

Throttling introduced in #12 helps with request flood, but there is a separate problem of the lack of request timeouts in web browser. Some requests can take a very long time and will suffocate request queue because they have no built-in timeout (namely /api/v0/refs):

This also means we can't use js-ipfs-http-client because it does not support cancellations: https://github.com/ipfs/js-ipfs-http-client/issues/694. For this very reason js-ipfs does not use ipfs-http-client for preload calls to /api/v0/refs: instead it is using manual fetch with AbortController in web browser (preload-browser.js) and req.abort in Node (preload-nodejs.js)

We need to do the same, or use js-ipfs-http-client-lite (add missing commands if needed).

@jacobheun @alanshaw thoughts on which way is better? Is this library aimed only at browsers, or will it be used in Node as well?

[alanshaw]

It'll be used in all environments.

If we call provide every CID we add (which I think we do) then we don't need the recursive flag. This will reduce the RTT for each call to provide significantly.

[achingbrain]

This module has an internal request queue so this should be fixed now.