WEBVTT

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<v Jose>Hi, welcome back.</v>

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Just a quick aside to warn you of something that can happen

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in these asynchronous programmes.

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Because we're running until_complete

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and we're gathering all the tasks here,

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potentially if one task takes a really long time

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or maybe takes a few minutes or a few hours to,

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for the server to respond, we want to say,

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you know, if it takes more than 30 seconds,

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I just wanna terminate this and treat it as an error.

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Sometimes the servers won't send you an error,

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they just won't send you anything

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and you'll be waiting for content for a long time.

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This run_until-complete means

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that your programme won't actually finish

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until all of the tasks have given you something.

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So, it can be a bit dangerous if you don't have anything

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to say timeout after X number of seconds.

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Aiohttp in the latest version comes

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with something called the async_timeout

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which you can import, async_timeout,

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that you can use as a timeout

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in an asynchronous environment.

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You can just say async with async_timeout.timeout.

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Maybe 10 seconds, 10 seconds is a pretty reasonable number,

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I think.

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So, now if this session.get takes longer than 10 seconds,

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it's gonna be cancelled and an exception is gonna be raised.

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And as I said, that can be quite handy

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for when something does take a long time.

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For Google, this is not gonna be a problem,

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but maybe for a book scraping and business,

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it could be a bit of an issue.

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So, that's it for this video, just wanted to share

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with you this async_timeout as something that exists

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and that you can use.

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I'll see you in the next one.