Gitea supports acting as an OAuth2 provider to allow third party applications to access its resources with the user's consent. This feature is available since release 1.8.0.
At the moment Gitea only supports the [**Authorization Code Grant**](https://tools.ietf.org/html/rfc6749#section-1.3.1) standard with additional support of the following extensions:
To use the Authorization Code Grant as a third party application it is required to register a new application via the "Settings" (`/user/settings/applications`) section of the settings.
Currently Gitea does not support scopes (see [#4300](https://github.com/go-gitea/gitea/issues/4300)) and all third party applications will be granted access to all resources of the user and their organizations.
Gitea supports both confidential and public client types, [as defined by RFC 6749](https://datatracker.ietf.org/doc/html/rfc6749#section-2.1).
For public clients, a redirect URI of a loopback IP address such as `http://127.0.0.1/` allows any port. Avoid using `localhost`, [as recommended by RFC 8252](https://datatracker.ietf.org/doc/html/rfc8252#section-8.3).
The `CLIENT_ID` can be obtained by registering an application in the settings. The `STATE` is a random string that will be send back to your application after the user authorizes. The `state` parameter is optional but should be used to prevent CSRF attacks.
2. Using the provided `code` from the redirect, you can request a new application and refresh token. The access token endpoints accepts POST requests with `application/json` and `application/x-www-form-urlencoded` body, for example:
The `CLIENT_SECRET` is the unique secret code generated for this application. Please note that the secret will only be visible after you created/registered the application with Gitea and cannot be recovered. If you lose the secret you must regenerate the secret via the application's settings.