At the moment Forgejo 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. To test or debug you can use the web-tool https://oauthdebugger.com/.
Forgejo supports scoped access tokens, which allow users to restrict tokens to operate only on selected url routes. Scopes are grouped by high-level API routes, and further refined to the following:
-`read`: `GET` routes
-`write`: `POST`, `PUT`, `PATCH`, and `DELETE` routes (in addition to `GET`)
| **read:issue** | Grants read access for issues operations, such as getting issue comments, issue attachments, and milestones. |
| **write:issue** | Grants read/write/delete access for issues operations, such as posting or editing an issue comment or attachment, and updating milestones. |
| **misc** | miscellaneous and settings top-level API routes. |
| **read:misc** | Grants read access to miscellaneous operations, such as getting label and gitignore templates. |
| **write:misc** | Grants read/write/delete access to miscellaneous operations, such as markup utility operations. |
| **notification** | `notification/*` API routes: user notification operations. |
| **read:notification** | Grants read access to user notifications, such as which notifications users are subscribed to and read new notifications. |
| **write:notification** | Grants read/write/delete access to user notifications, such as marking notifications as read. |
| **organization** | `orgs/*` and `teams/*` API routes: Organization and team management operations. |
| **read:organization** | Grants read access to org and team status, such as listing all orgs a user has visibility to, teams, and team members. |
| **write:organization** | Grants read/write/delete access to org and team status, such as creating and updating teams and updating org settings. |
| **package** | `/packages/*` API routes: Packages operations |
| **read:package** | Grants read access to package operations, such as reading and downloading available packages. |
| **write:package** | Grants read/write/delete access to package operations. Currently the same as `read:package`. |
| **repository** | `/repos/*` API routes except `/repos/issues/*`: Repository file, pull-request, and release operations. |
| **read:repository** | Grants read access to repository operations, such as getting repository files, releases, collaborators. |
| **write:repository** | Grants read/write/delete access to repository operations, such as getting updating repository files, creating pull requests, updating collaborators. |
| **user** | `/user/*` and `/users/*` API routes: User-related operations. |
| **read:user** | Grants read access to user operations, such as getting user repo subscriptions and user settings. |
| **write:user** | Grants read/write/delete access to user operations, such as updating user repo subscriptions, followed users, and user settings. |
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 sent 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 endpoint 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 Forgejo and cannot be recovered. If you lose the secret, you must regenerate the secret via the application's settings.
3. Use the `access_token` to make API requests to access the user's resources.
### Public client (PKCE)
PKCE (Proof Key for Code Exchange) is an extension to the OAuth flow which allows for a secure credential exchange without the requirement to provide a client secret.
**Note**: Please ensure you have registered your OAuth application as a public client.
To achieve this, you have to provide a `code_verifier` for every authorization request. A `code_verifier` has to be a random string with a minimum length of 43 characters and a maximum length of 128 characters. It can contain alphanumeric characters as well as the characters `-`, `.`, `_` and `~`.
Using this `code_verifier` string, a new one called `code_challenge` is created by using one of two methods:
- If you have the required functionality on your client, set `code_challenge` to be a URL-safe base64-encoded string of the SHA256 hash of `code_verifier`. In that case, your `code_challenge_method` becomes `S256`.
- If you are unable to do so, you can provide your `code_verifier` as a plain string to `code_challenge`. Then you have to set your `code_challenge_method` as `plain`.
After you have generated this values, you can continue with your request.
1. Redirect the user to the authorization endpoint in order to get their consent for accessing the resources:
The `CLIENT_ID` can be obtained by registering an application in the settings. The `STATE` is a random string that will be sent back to your application after the user authorizes. The `state` parameter is optional, but should be used to prevent CSRF attacks.
![Authorization Page](/authorize.png)
The user will now be asked to authorize your application. If they authorize it, the user will be redirected to the `REDIRECT_URL`, for example:
2. Using the provided `code` from the redirect, you can request a new application and refresh token. The access token endpoint accepts POST requests with `application/json` and `application/x-www-form-urlencoded` body, for example:
```curl
POST https://[YOUR-FORGEJO-URL]/login/oauth/access_token