Multi-threaded API v2 handler

[sharkykh]

Fixes #4963

[p0psicles]

can e be changed to error?

[p0psicles]

Looks good. i'll approve, up to you to merge it.

[p0psicles]

Let's keep it up2date with develop?

[sharkykh]

There's still an issue that the errors generated inside the routes are not being handled correctly.
To test this just raise an exception inside one of the routes, GET /config for example..

[p0psicles]

Been testing this for a week now. Seems pretty stable.

[sharkykh]

Medusa/medusa/server/api/v2/base.py

Lines 89 to 95 in 688f4a6

	def blocking_call():
	try:
	return method(*args, **kwargs)
	except Exception as error:
	self._handle_request_exception(error)
	return IOLoop.current().run_in_executor(executor, blocking_call)

I still think that solution is a bit crude, but I don't have any better ideas at the moment.
That said, I do believe it's stable now, so I guess you can go ahead and merge...

[Rouzax]

@sharkykh
This also fulfills #3351
Does this mean that when I call the API it will give an acknowledge directly or will it still wait for the process to complete and it can just handle more "threads" at a time?

[p0psicles]

It can handle more threads. It will always wait for the process thats providing its result

[p0psicles]

Oh this is unrelated to 3351

[Rouzax]

Is the GUI still unresponsive when post processing?
If it is responsive that actually fulfils my request in the original #3351

[p0psicles]

I havent really noticed that myself. But ideally the periodic postprocessing should still be moved to a thread.

[Rouzax]

I do it when a download is done by calling the API. So in occasion when I browse Medusa it will hang because it is post processing in the back end.
Not a big issue. Not sure with the new threaded post processing if that is still the case.

[labrys]

One thing to watch for is locked threads due to failed post processing. They will lock up resources. This happens most commonly when trying to postprocess an invalid rar file.

[Rouzax]

Medusa will never encounter a rare in my environment as I already unrar files with a post process script that is kicked off when qbitorrent finishes the download, the last step is calling the Medusa api to post process.

[labrys]

@Rouzax It may not in your environment but it has been a repeat issue for users ever since before we forked from SickRage.