GitLab as OpenID Connect identity provider
This document is about using GitLab as an OpenID Connect identity provider to sign in to other services.
Introduction to OpenID Connect
OpenID Connect (OIDC) is a simple identity layer on top of the OAuth 2.0 protocol. It allows clients to:
- Verify the identity of the end-user based on the authentication performed by GitLab.
- Obtain basic profile information about the end-user in an interoperable and REST-like manner.
OIDC performs many of the same tasks as OpenID 2.0, but is API-friendly and usable by native and mobile applications.
On the client side, you can use OmniAuth::OpenIDConnect for Rails applications, or any of the other available client implementations.
The GitLab implementation uses the doorkeeper-openid_connect gem, refer to its README for more details about which parts of the specifications are supported.
Enabling OpenID Connect for OAuth applications
Refer to the OAuth guide for basic information on how to set up OAuth
applications in GitLab. To enable OIDC for an application, all you have to do
is select the openid scope in the application settings.
Shared information
The following user information is shared with clients:
| Claim | Type | Description |
|---|---|---|
sub
| string
| The ID of the user |
sub_legacy
| string
| An opaque token that uniquely identifies the user Deprecation notice: this token isn’t stable because it’s tied to the Rails secret key base, and is provided only for migration to the new stable sub value available from GitLab 11.1
|
auth_time
| integer
| The timestamp for the user’s last authentication |
name
| string
| The user’s full name |
nickname
| string
| The user’s GitLab username |
email
| string
| The user’s email address This is the user’s primary email address if the application has access to the email claim and the user’s public email address otherwise
|
email_verified
| boolean
| Whether the user’s email address was verified |
website
| string
| URL for the user’s website |
profile
| string
| URL for the user’s GitLab profile |
picture
| string
| URL for the user’s GitLab avatar |
groups
| array
| Names of the groups the user is a member of |
The claims sub, sub_legacy, email and email_verified are included in the ID token, all other claims are available from the /oauth/userinfo endpoint used by OIDC clients.