reflex-magic-link-auth

Generate and verify "magic link" one time passwords for user authentication without complex registration flows.

Installation

pip install reflex-magic-link-auth

Usage

See magic_link_auth_demo/magic_link_auth_demo.py for a complete example.

1. Collect the User email

You can use a simple form with a single input field and button, like the example, or present a form prompting for more information, such as a name, address, zip code, etc. Any additional data should be associated with the provided email as the main key for the account.

2. Substate from MagicLinkAuthState

The substate which handles the authentication form submission should be a substate of reflex_magic_link_auth.MagicLinkAuthState (alternatively, it may get an instance of this state via .get_state API).

3. Generate the OTP

When the user submits the form, generate a one time password by calling ._generate_otp and providing the email address.

This function returns a 2-tuple:

• The latest record associated with the email address
• The one time password in plaintext

If the record is None, then the email address was invalid, or some other problem occured (ensure database migration has been applied).

If the record is returned, but the OTP is None, then the user has exceeded the configured rate limit and cannot receive a new token for a while.

4. Send the Magic Link

Either on page on_load or some component on_mount should trigger reflex_magic_link_auth.MagicLinkAuthState.get_base_url to ensure the state knows the correct frontend URL when formatting the magic links.

Pass the record and otp to reflex_magic_link_auth.MagicLinkAuthState._get_magic_link to get a URL that, when accessed will log the user in to the app.

While this component contains an example mailgun provider, generally it is up to you to actually email the link to the user.

5. User Accesses the Magic Link

The user clicks the link in their email, and the page mounted at reflex_magic_link_auth.constants.AUTH_ROUTE will validate the token and redirect to the URL specified in the query param redir.

6. Verifying Access

Any event handlers which depend on user session validity should check the computed var reflex_magic_link_auth.MagicLinkAuthState.session_is_valid to determine if the user is logged in and the session has not expired.

A persistent external identifier hashed over the email address is provided at reflex_magic_link_auth.MagicLinkAuthState.auth_session.persistent_id. When interoperating with other user information systems, this ID can be used to uniquely identifer a user originating from reflex-magic-link-auth.

7. Logout

To log the user out, trigger the event handler reflex_magic_link_auth.MagicLinkAuthState.logout.