fix: session object was never used in aiohttp request (#700)

[greshilov]

Fix for #700

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[greshilov]

@googlebot I signed it!

[arithmetic1728]

why raise the error here?

[greshilov]

Modifying the session object provided by the user is inappropriate in this place, so we can't disable auto_decompress ourselves. Remaining options are:

• Ignore the session object provided by the user and leave the self.session = None. Log error in console.
• Raise the error to stop execution and warn user, that's something went wrong with one's session.

I chose the latter option because it's better to fail early in my opinion. A user may not notice that one's session object is ignored.

[arithmetic1728]

Sorry I meant why auto_decompress=True are not supported. I am not familiar with aiohttp.

I think in this PR you also need to pass auto_decompress=False to https://github.com/googleapis/google-auth-library-python/blob/master/system_tests/system_tests_async/conftest.py#L29 to make the system test work.

[greshilov]

Sorry I meant why auto_decompress=True are not supported. I am not familiar with aiohttp.

I think in this PR you also need to pass auto_decompress=False to https://github.com/googleapis/google-auth-library-python/blob/master/system_tests/system_tests_async/conftest.py#L29 to make the system test work.

Ah, auto_decompress=True is supported by aiohttp, but this library prefers to do decompression on its own:

google-auth-library-python/google/auth/transport/_aiohttp_requests.py

Lines 80 to 88 in 04c870a

	async def content(self):
	# Load raw_content if necessary
	await self.raw_content()
	if self._is_compressed():
	decoder = urllib3.response.MultiDecoder(
	self._response.headers["Content-Encoding"]
	)
	decompressed = decoder.decompress(self._raw_content)
	return decompressed

I've made required changes in conftest.py.

[arithmetic1728]

Ah I see. Thank you! The system test is still failing. I will take a look at why it failed.

[greshilov]

@arithmetic1728 I hope I found the problem. ASYNC_REQUESTS_SESSION is created outside the pytest-asyncio context and thus assigned to the wrong event loop.

ASYNC_REQUESTS_SESSION = aiohttp.ClientSession(auto_decompress=False)

I moved the session creation process to a separate fixture. Hope it helps.

[arithmetic1728]

@greshilov Great! Thank you!