[Python-Dev] Asynchronous context manager in a typical network server

[Andrew Barnert]

On Dec 18, 2015, at 10:25, Szieberth Ádám <sziebadam at gmail.com> wrote:
> 
>> - In theory, instead of waiting for a Future that is cancelled by a
>> handler, you should be able to use asyncio.sleep() with a very large number
>> (e.g. a million seconds).
> 
> I was thinking on this too but it seemed less explicit to me than awaiting a 
> pure Future with a short comment. Moreover, even millions of seconds can pass.

Yes, and these are really fun to debug. When a customer comes to you with "it was running fine for a few months and then suddenly it started going crazy, but I can't reproduce it", unless you happen to remember that you decided 10 million seconds was "forever" and ask whether "a few months" specifically means a few days short of 4 months... (At least with 24 and 49 days I know to look for which library used a C integer for milliseconds.)

Really, I don't see anything wrong with the way the OP wrote it. Is that just because I have bad C habits (/* Useless select because there's no actual sleep function that allows SIGUSR to wake us without allowing all signals to wake us that works on both Solaris and IRIX */) and it really does look misleading to people who aren't warped like that?

If so, would it be worth having an actual way to say "sleep forever (until canceled)"? Even if, under the covers, this only sleeps for 50000 years or so, a Y52K problem that can be solved by just pushing a new patch release for Python instead of for every separate server written in Python is probably a bit nicer. :)