Exceptions¶

fastauth.exceptions.FastAuthError ¶

Bases: Exception

Base exception for all FastAuth errors.

Raised when the :class:~fastauth.config.FastAuthConfig is invalid.

Common causes: missing secret, no providers configured, or a session_strategy="database" without a session_backend.

Raised when an optional dependency is not installed.

FastAuth uses optional extras (jwt, oauth, sqlalchemy, etc.). This error tells you exactly which package to install and which extra to use.

Parameters:

Name	Type	Description	Default
`package`	`str`	The missing Python package name.	required
`extra`	`str`	The FastAuth extra that includes the package.	required

Raised when authentication fails.

Covers bad credentials, expired tokens, revoked sessions, and similar scenarios where the identity of the requester cannot be confirmed.

Raised when attempting to register an email address that is already taken.

Raised when a user lookup returns no result.

Raised when a token is invalid, expired, or has been revoked.

Raised when an auth provider returns an error.

Typically wraps OAuth provider failures (bad code, revoked tokens, etc.).