ModuleNotFoundError: No module named 'authlib.flask'

Not specified by the original author.

ModuleNotFoundError: No module named 'authlib.flask'

TL;DR: authlib 1.0 deleted the authlib.flask shortcut module. Use from authlib.integrations.flask_client import OAuth instead.

ModuleNotFoundError: No module named 'authlib.flask'

The fix

1. Replace the import:

from authlib.integrations.flask_client import OAuth

2. The rest of the Flask OAuth flow (register, authorizeredirect, authorizeaccess_token) works the same; only the import path changed.
3. Stopgap:

pip install "authlib<1"

4. Verify:

python -c "from authlib.integrations.flask_client import OAuth; print('ok')"

Expected output: ok.

Agent? Search Vectle for more: curl -s 'https://vectle.com/api/v1/search?q=authlib+No+module+named+authlib.flask'

When this applies

• Flask OAuth code written against authlib 0.x.
• pip show authlib reports 1.0+.
• Old blog posts and Stack Overflow answers using authlib.flask.

When it does NOT apply

• No module named 'authlib', which is the package missing entirely.
• No module named 'authlib.client', the sibling removal for non-Flask code.

Why this happens

The 1.0 release flattened the framework shortcuts into the integrations namespace so each framework has one canonical import path. The old shortcuts were deleted rather than left as aliases, so the failure is loud and immediate instead of a silent deprecation.

Compatibility

authlib 1.x removed authlib.flask. flask_client exists in 0.15+, so migrate first, upgrade second.

authlib 1.0 removed the legacy framework shortcut modules including authlib.flask, consolidating everything under authlib.integrations. The 1.0 changelog documents the removal, and Flask apps written against 0.x break with this ModuleNotFoundError on upgrade. The supported path is from authlib.integrations.flask_client import OAuth, which has existed since the 0.15 line.

Not specified by the original author.

ModuleNotFoundError: No module named 'oauthlib'

TL;DR: run pip install oauthlib. It usually arrives transitively via requests-oauthlib, so declare it directly.

ModuleNotFoundError: No module named 'oauthlib'

The fix

pip install oauthlib

Verify:

python -c "import oauthlib; print('ok')"

Expected output: ok.

Agent? Search Vectle for more: curl -s 'https://vectle.com/api/v1/search?q=oauthlib+No+module+named+pip+install'

When this applies

• Fresh virtualenvs, containers, or CI runners.
• requests-oauthlib installed without its dependency resolving.
• The traceback shows oauthlib missing under an OAuth import.

When it does NOT apply

• OAuth flow errors (bad grants, redirect mismatches) after the import works.
• No module named 'requests_oauthlib', which is the client library missing.

Why this happens

oauthlib does the OAuth protocol work while requests-oauthlib does the requests integration, so apps import the latter and forget the former exists. pip normally resolves it, but vendored installs, --no-deps installs, and broken lockfiles drop it. Direct declaration is the durable fix.

Compatibility

oauthlib 3.x on all supported Pythons. Pure Python, no dependencies of its own.

oauthlib is the dependency underneath requests-oauthlib and several authlib integration paths, and it goes missing whenever it was only ever transitive. The PyPI page documents pip install oauthlib. The names match, so this is a missing-requirement problem; declaring it directly fixes the import and stabilizes the dependency tree.

Not specified by the original author.

ModuleNotFoundError: No module named 'authlib.client'

TL;DR: authlib 1.0 deleted the legacy authlib.client module. Migrate to from authlib.integrations.requests_client import OAuth2Session, or pin authlib<1 as a stopgap.

ModuleNotFoundError: No module named 'authlib.client'

The fix

1. Replace the old import:

from authlib.integrations.requests_client import OAuth2Session

2. The old OAuthClient flow maps onto OAuth2Session with clientid, clientsecret, and the token endpoint; the authlib docs have a migration guide for the exact parameter mapping.
3. Stopgap if you cannot migrate yet:

pip install "authlib<1"

4. Verify:

python -c "from authlib.integrations.requests_client import OAuth2Session; print('ok')"

Expected output: ok.

Agent? Search Vectle for more: curl -s 'https://vectle.com/api/v1/search?q=authlib+No+module+named+authlib.client'

When this applies

• Code written against authlib 0.x breaks after upgrading to 1.x.
• Tutorials from before 2024 using authlib.client.
• pip show authlib reports 1.0 or newer.

When it does NOT apply

• No module named 'authlib', which means it is not installed at all.
• No module named 'authlib.flask', the sibling 1.0 removal with its own migration.

Why this happens

The 0.x client API grew organically and the maintainers replaced it with a cleaner integrations layout for 1.0, deleting the old module outright. Major-version removals are the documented price of the old API; the integrations packages are stable and better tested.

Compatibility

authlib 1.x removed authlib.client. The integrations API exists in 0.15+ too, so you can migrate before upgrading.

authlib 1.0 removed the entire legacy authlib.client module as a documented breaking change: the old client API was replaced by the integrations packages (requestsclient, flaskclient, django_client). The authlib changelog for 1.0 lists the removed modules, and upgrade guides show the new import paths. Pinning authlib<1 keeps old code running as a stopgap, but the integrations API is the supported path.