Fix #679: allow async class methods as dependencies

[frankie567]

This is the fix for issue #679: allow to use async class methods as dependencies.

Before, such methods were not correctly detected as coroutine and thus were not awaited but rather sent to run_in_threadpool. We ended up then injecting the coroutine instead of its result.

I've used inspect.isroutine, instead of doing inspect.isfunction(call) or inspect.ismethod(call). It seems to fulfill our need while saving us a check.

I also took this opportunity to add some unit tests to verify the different use cases regarding class dependencies (callable, async callable, sync methods and async methods).

It could also be interesting to mention those possibilities in the Classes as Dependencies section of the documentation. What do you think?

[frankie567]

The CI fails because of linting issues (not related to my changes). Should I fix this or do you prefer a separate PR?

[euri10]

Black is not pinned and indeed it raises issues it wasn't before Le mar. 5 nov. 2019 à 9:11 AM, François Voron <notifications@github.com> a écrit :

…

The CI fails because of linting issues (not related to my changes). Should I fix this or do you prefer a separate PR? — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#681>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAINSPUMXYAZO6GWAXNDOCDQSETEFANCNFSM4JI674JQ> .

[frankie567]

Yeah, they fixed something regarding function parameters/trailing commas. Should be quite straightforward to fix, but maybe it should live in another PR. I'll do that quickly.

EDIT: See #682.

[prostomarkeloff]

@tiangolo what's about merging it?

[codecov]

Codecov Report

Merging #681 into master will not change coverage.
The diff coverage is 100%.

@@          Coverage Diff           @@
##           master   #681    +/-   ##
======================================
  Coverage     100%   100%            
======================================
  Files         271    276     +5     
  Lines        7011   7871   +860     
======================================
+ Hits         7011   7871   +860

Impacted Files	Coverage Δ
fastapi/dependencies/utils.py	100% <100%> (ø)	⬆️
tests/test_dependency_class.py	100% <100%> (ø)
...ration_advanced_configurations/test_tutorial003.py	100% <0%> (ø)	⬆️
tests/test_jsonable_encoder.py	100% <0%> (ø)	⬆️
fastapi/openapi/utils.py	100% <0%> (ø)	⬆️
fastapi/dependencies/models.py	100% <0%> (ø)	⬆️
docs/src/response_model/tutorial003.py	100% <0%> (ø)	⬆️
fastapi/concurrency.py	100% <0%> (ø)	⬆️
fastapi/applications.py	100% <0%> (ø)	⬆️
... and 17 more

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[frankie567]

Rebased the branch with fixed linting to have the pipeline checked 👍

[tiangolo]

Great, thank you @frankie567 ! Thanks for implementing it, and adding extended tests. 🤓 🚀 🍰 🎉

And thanks everyone for the discussion.