[Google Calendar] Stack trace when discovering for the first time

Hi there,

I recently acquired a new email address with Google workspace for the first time in a few years. I'm trying to setup synchronisation using oauth2 (I believe I'd made use of app passwords before).

With the following remote configuration:

[storage calendar_redacted_remote]
client_id = "<redacted>.apps.googleusercontent.com"
client_secret = "<redacted>"
token_file = "/home/john/.cache/redacted-access-tokens"
type = "google_calendar"

When I run vdirsyncer -vdebug discover, I receive a stacktrace:

john@mars:~/ > vdirsyncer -vdebug discover
Discovering collections for pair calendar_redacted
Opening https://accounts.google.com/o/oauth2/v2/auth?response_type=code&client_id=371803114843-1hggirbdliohotaeuqe41575n9af4di9.apps.googleusercontent.com&redirect_uri=http%3A%2F%2F127.0.0.1%3A56813&scope=https%3A%2F%2Fwww.googleapis.com%2Fauth%2Fcalendar&state=z6DtYIiaMSREKva8q2tp8fqRAycK4x&access_type=offline&approval_prompt=force ...                                                                            M
Follow the instructions on the page.
"GET /?state=z6DtYIiaMSREKva8q2tp8fqRAycK4x&code=4/0ASVgi3J4DYu9DESpaHEm9RbDAA6lNJJMUiNEqiCngYx7R15ygO6Hc7pm4vkwNYVxzFyzww&scope=https://www.googleapis.com/auth/calendar HTTP/1.1" 200 28
debug: server handled request!
debug: authorization_response: https://127.0.0.1:56813/?state=z6DtYIiaMSREKva8q2tp8fqRAycK4x&code=4/0ASVgi3J4DYu9DESpaHEm9RbDAA6lNJJMUiNEqiCngYx7R15ygO6Hc7pm4vkwNYVxzFyzww&scope=https://www.googleapis.com/auth/calendar
debug:   File "/nix/store/dmgi0wfaasf6k3x01shrvqfvbv0bl0bx-python3.12-vdirsyncer-0.19.3/lib/python3.12/site-packages/vdirsyncer/cli/discoverbug:                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^.py", line 265, in _print_collections               = await self._discover()

debug:     discovered = await get_discovered()
debug:                  ^^^^^^^^^^^^^^^^^^^^^^
debug:   File "/nix/store/dmgi0wfaasf6k3x01shrvqfvbv0bl0bx-python3.12-vdirsyncer-0.19.3/lib/python3.12/site-packages/vdirsyncer/cli/discover.py", line 178, in get_self
debug:     self._discovered = await self._discover()
debug:                        ^^^^^^^^^^^^^^^^^^^^^^
debug:   File "/nix/store/dmgi0wfaasf6k3x01shrvqfvbv0bl0bx-python3.12-vdirsyncer-0.19.3/lib/python3.12/site-packages/vdirsyncer/cli/discover.py", line 187, in _discover
debug:     return handle_storage_init_error(self._cls, self._config)
debug:            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
debug:   File "/nix/store/dmgi0wfaasf6k3x01shrvqfvbv0bl0bx-python3.12-vdirsyncer-0.19.3/lib/python3.12/site-packages/vdirsyncer/cli/discover.py", line 183, in _discover
debug:     discovered = await aiostream.stream.list(self._cls.discover(**self._config))
debug:                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
debug:   File "/nix/store/zs5vdy5d77fmk757qc3v9x6v7qjvnn13-python3.12-aiostream-0.6.4/lib/python3.12/site-packages/aiostream/core.py", line 60, in wait_stream
debug:     async for item in streamer:
debug:   File "/nix/store/zs5vdy5d77fmk757qc3v9x6v7qjvnn13-python3.12-aiostream-0.6.4/lib/python3.12/site-packages/aiostream/stream/aggregate.py", line 89, in list
debug:     async for item in streamer:
debug:   File "/nix/store/dmgi0wfaasf6k3x01shrvqfvbv0bl0bx-python3.12-vdirsyncer-0.19.3/lib/python3.12/site-packages/vdirsyncer/storage/dav.py", line 485, in discover
debug:     async for collection in d.discover():
debug:   File "/nix/store/dmgi0wfaasf6k3x01shrvqfvbv0bl0bx-python3.12-vdirsyncer-0.19.3/lib/python3.12/site-packages/vdirsyncer/storage/dav.py", line 271, in discover
debug:     for c in await self.find_collections():
debug:              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
debug:   File "/nix/store/dmgi0wfaasf6k3x01shrvqfvbv0bl0bx-python3.12-vdirsyncer-0.19.3/lib/python3.12/site-packages/vdirsyncer/storage/dav.py", line 223, in find_collections
debug:     rv = await aiostream.stream.list(self._find_collections_impl(""))
debug:          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
debug:   File "/nix/store/zs5vdy5d77fmk757qc3v9x6v7qjvnn13-python3.12-aiostream-0.6.4/lib/python3.12/site-packages/aiostream/core.py", line 60, in wait_stream
debug:     async for item in streamer:
debug:   File "/nix/store/zs5vdy5d77fmk757qc3v9x6v7qjvnn13-python3.12-aiostream-0.6.4/lib/python3.12/site-packages/aiostream/stream/aggregate.py", line 89, in list
debug:     async for item in streamer:
debug:   File "/nix/store/dmgi0wfaasf6k3x01shrvqfvbv0bl0bx-python3.12-vdirsyncer-0.19.3/lib/python3.12/site-packages/vdirsyncer/storage/dav.py", line 253, in _find_collections_impl
debug:     r = await self.session.request(
debug:         ^^^^^^^^^^^^^^^^^^^^^^^^^^^
debug:   File "/nix/store/dmgi0wfaasf6k3x01shrvqfvbv0bl0bx-python3.12-vdirsyncer-0.19.3/lib/python3.12/site-packages/vdirsyncer/storage/google.py", line 68, in request
debug:     await self._init_token()
debug:   File "/nix/store/dmgi0wfaasf6k3x01shrvqfvbv0bl0bx-python3.12-vdirsyncer-0.19.3/lib/python3.12/site-packages/vdirsyncer/storage/google.py", line 154, in _init_token
debug:     self._token = await session.fetch_token(
debug:                   ^^^^^^^^^^^^^^^^^^^^^^^^^^
debug:   File "/nix/store/n3b3gmqvwwzv16p6s6akrzjqhb2jlfyj-python3.12-aiohttp-oauthlib-0.1.0/lib/python3.12/site-packages/aiohttp_oauthlib.py", line 379, in fetch_token
debug:     self._client.parse_request_body_response(text, scope=self.scope)
debug:   File "/nix/store/ma1iqvarq124xyyq37knsgddzg9v7lqy-python3.12-oauthlib-3.2.2/lib/python3.12/site-packages/oauthlib/oauth2/rfc6749/clients/base.py", line 427, in parse_request_body_response
debug:     self.token = parse_token_response(body, scope=scope)
debug:                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
debug:   File "/nix/store/ma1iqvarq124xyyq37knsgddzg9v7lqy-python3.12-oauthlib-3.2.2/lib/python3.12/site-packages/oauthlib/oauth2/rfc6749/parameters.py", line 441, in parse_token_response
debug:     validate_token_parameters(params)
debug:   File "/nix/store/ma1iqvarq124xyyq37knsgddzg9v7lqy-python3.12-oauthlib-3.2.2/lib/python3.12/site-packages/oauthlib/oauth2/rfc6749/parameters.py", line 448, in validate_token_parameters
debug:     raise_from_error(params.get('error'), params)
debug:   File "/nix/store/ma1iqvarq124xyyq37knsgddzg9v7lqy-python3.12-oauthlib-3.2.2/lib/python3.12/site-packages/oauthlib/oauth2/rfc6749/errors.py", line 399, in raise_from_error
debug:     raise cls(**kwargs)
warning: Failed to discover collections for calendar_redacted_remote, use `-vdebug` to see the full traceback.

john@mars:~/ > vdirsyncer --version
vdirsyncer, version 0.19.3

With these same credentials, if I run:

oauth2l fetch --credentials mail-redacted-oauth2.json \
    --scope 'https://www.googleapis.com/auth/calendar' \
    --cache= --output_format=json

I seem able to produce a token.

Reproduce the issue with vdirsyncer -vdebug discover, then read vdirsyncer/storage/google.py around _init_token and vdirsyncer/storage/dav.py around collection discovery. Compare the OAuth token response path with the reported oauth2l result and trace the exception handling. Done means first-time Google Calendar discovery no longer produces an unhandled stack trace and reports the failure clearly if token acquisition still fails.