Fire and forget async ctx blocks anti-pattern #70
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gsalgado
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pipermerriam
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Jun 9, 2020
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I think that the example code here needs to be fleshed out a bit more. Ideally using something self-contained that doesn't lean on our trinity architecture which won't be familiar to everyone.
Example in-my-opinion should include the implementation of the async context manager, showing it returning a future/task type object, and then a version of the code you posted showing how you can end up with a dead background task if you don't include awaiting it as well.
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@pipermerriam care to have another look? I've added a self-contained example but also left the reference to the trinity code where I first noticed this pattern as I think it's good to have an example from real production code |
cburgdorf
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Jun 15, 2020
| ``` | ||
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| In the above example, if the background task running `producer(stream_writer)` terminates without | ||
| closing the the writer, the `run()` function would continue running indefinitely and the exception |
cburgdorf
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Jun 16, 2020
| async with acmanager(writer) as streaming_task: | ||
| await asyncio.wait( | ||
| [consumer(reader), streaming_task], | ||
| return_when=asyncio.FIST_COMPLETED) |
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