You can connect Metabase to your identity provider using JSON Web Tokens (JWT) to authenticate people.
Types of authentication Metabase supports with JWT
Metabase supports two types of OAuth 2 authentication with JWT:
- Authorization Code Flow
- Authorization Code Flow with PKCE
PKCE stands for Proof-Key for Code Exchange, and it’s a way to extend the Authorization Code Flow to incorporate random keys generated on demand. For more on these flows, see the Wikipedia entry on OAuth.
Typical flow for a JWT-based SSO interaction with Metabase
Assuming your site is localhost serving on port 3000:
- Person attempts to view a question, e.g.,
- If the person isn’t logged in, Metabase redirects them to
- Retaining the original
/question/1-superb-questionURI, Metabase redirects the person to the SSO provider (the authentication app).
- Person logs in using the basic form.
- In the event of a successful sign-in, your authentication app should issue a GET request to your Metabase endpoint with the token and the “return to” URI:
- Metabase verifies the JSON Web Token, logs the person in, then redirects the person to their original destination,
Enabling JWT authentication
Navigate to the Admin>Settings section of the Admin area, then click on the Authentication tab. Click the Configure button in the JWT section of this page, and you’ll see this form:
Click the toggle at the top of the form to enable JWT-based authentication. Make sure to set the toggle to Enabled, otherwise JWT authentication won’t work, even if all of your other settings are correct.
Here’s a breakdown of each of the settings:
JWT Identity Provider URI: This is where Metabase will redirect login requests. That is, it’s where your users go to log in through your identity provider.
String Used by the JWT Signing Key: The string used to seed the private key used to validate JWT messages. Both Metabase and the authentication app should have the same JWT signing key.
User attribute configuration (optional)
These are additional settings you can fill in to pass user attributes to Metabase.
- Email attribute: the key to retrieve each JWT user’s email address.
- First Name attribute: the key to retrieve each JWT user’s first name.
- Last Name attribute: if you guessed that this is the key to retrieve each JWT user’s last name, well then you have been paying attention.
You can use your JWT to assign Metabase users to custom groups by following these steps:
- Add this to your JWT:
- In the Admin Panel in Metabase, go to the Authentication tab of the Settings section and click the Configure button on JWT. On this screen, turn on the toggle under “SYNCHRONIZE GROUP MEMBERSHIPS”.
- Next, click Edit Mappings. In this modal, type in the name of one of your groups as defined in the JWT, then click Add. In the row that appears, click the dropdown to pick the Metabase group that this should map to. Repeat this for each of the groups you want to map.
Disabling password login
Once you have set up your JWT authentication and confirmed that it’s working, if you want to disable the option for users to log in via username and password, return to Admin > Settings > Authentication and scroll to the bottom. A toggle should now be visible that allows you disable password authentication.
Note about Azure
If you’re using Azure, you may need to use Azure AD B2C. Check out their tokens overview.
Example code using JWT-based authentication
You can find example code that uses JWT authentication in the SSO examples repository.