Refactor Microphone to use callback mode

[lugia19]

Proposed changes

Refactored the Microphone class:

• Add the ability to select a playback device instead of always using the default one
• Utilize PyAudio's callback mode instead of a While True loop (more appropriate for this usecase)
• Change self.exit to be an event rather than a bool with a lock
• Only check for push_callback being a coroutine during init, and wrap to be synchronous it if it is

Types of changes

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• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update or tests (if none of the other choices apply)

Checklist

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• I have read the CONTRIBUTING doc
• Lint and unit tests pass locally with my changes
• I have added tests that prove my fix is effective or that my feature works
• I have added necessary documentation (if appropriate)
• Any dependent changes have been merged and published in downstream modules

Further comments

N/A

[davidvonthenen]

Hi @lugia19

Thanks for this PR. This looks pretty interesting! Will check this out and get back to provide some feedback!

[davidvonthenen]

Also, just a heads up @lugia19 I haven't taken a look, but just a reminder that interfaces cannot change until a major release meaning how a user implements their code should not break (need to preserve backward compatibility).

If we need to break the interfaces, we can do something special for the microphone class since they aren't really a part of the API. If it needs to happen (ie breaking changes), then we probably should discuss.

I see you are still making changes, ping me when ready to review.

[lugia19]

@dvonthenen Oh it's ready, that was the last change I had to do since I realized I implemented the asyncio callback stuff in a non-thread safe way.

As far as the interface, I'm aware - I made sure the interface would remain the same (bar the new optional argument for the init to set the input device, but I made it so by default not including it maintains the same behavior as before). There shouldn't be any differences.

[davidvonthenen]

Cool. Will take a look when I get a free moment.

[davidvonthenen]

Very cool! Thanks for this contribution! Left some feedback for you. If you can also squash commits after updating, that would be awesome!

[davidvonthenen]

Few other things I just noticed and we are good to merge.

[davidvonthenen]

Sweeeeet! Yay!

[davidvonthenen]

Thanks for your help with this @lugia19 !