YouCompleteMe/autoload
Homu dc44597674 Auto merge of #2514 - micbou:connect-timeout, r=Valloric
[READY] Rely on connect timeout instead of checking that the server is alive

Currently, we always check that the ycmd process is up (with the `IsServerAlive` method) before sending a request. Without this check, each request could block Vim until a `NewConnectionError` exception is raised if the server crashed. This is the case on Windows where it takes ~1s before the exception is raised which makes Vim unusable. However, even with this check, Vim may still be blocked in the following cases:
 - the server crashes just after the check but before sending the request;
 - the server is up but unresponsive (e.g. its port is closed).

To avoid both cases, we instead use [the connect timeout parameter from Requests](http://docs.python-requests.org/en/master/user/advanced/?highlight=connect%20timeout#timeouts) and set it to a duration sufficiently short (10 ms) that the blocking can't be noticed by the user. Since the server is supposed to run locally (this is what YCM is designed for), 10ms is largely enough to establish a connection.

The `IsServerAlive` check is removed almost everywhere except in `OnFileReadyToParse` because we still want to notify the user if the server crashed.

This change makes it possible to not have to [wait for the server to be healthy before sending asynchronous requests](https://github.com/Valloric/YouCompleteMe/blob/master/python/ycm/client/base_request.py#L137-L138). This will dramatically improve startup time (see issue #2085) and fixes #2071. Next PR once this one is merged.

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2017-01-26 19:01:59 +09:00
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youcompleteme.vim Auto merge of #2514 - micbou:connect-timeout, r=Valloric 2017-01-26 19:01:59 +09:00