Comment 21 for bug 1908452

@dannf - Thanks for the great deep dive!

It seems the issue is in python3-simplestreams. According to [1] "Nearly all production code should use this parameter in nearly all requests. Failure to do so can cause your program to hang indefinitely"

The timeout needs to be set in RequestsUrlReader which is fairly deep in SimpleStreams code, MAAS does not directly interact with it at all. simplestreams uses Urllib2UrlReader as an alternative if requests isn't available and no timeout is set there either. RequestsUrlReader/Urllib2UrlReader is called by UrlMirrorReader which MAAS does call.

We need to figure out a good default timeout value for both RequestsUrlReader and Urllib2UrlReader. We also need to determine whether this should be configurable by the caller or not, MAAS will most likely use the default value.

[1] https://requests.readthedocs.io/en/master/user/quickstart/#timeouts