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doc/github-authentication.markdown

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+Github Authentication
+=====================
+
+Requirements
+------------
+
+OAuth Github API credentials (available in your [Settings > Applications > Developer applications](https://github.com/settings/applications))
+
+How does this work?
+-------------------
+
+The Github authentication in Kanboard uses the [OAuth 2.0](http://oauth.net/2/) protocol, so any user of Kanboard can be linked to a Github account.
+
+That means you can use your Github account to login on Kanboard.
+
+How to link a Github account
+----------------------------
+
+1. Go to your user profile
+2. Click on **External accounts**
+3. Click on the link **Link my Github Account**
+4. You are redirected to the **Github Authorize application form**
+5. Authorize Kanboard by clicking on the button **Accept**
+6. Your account is now linked
+
+Now, on the login page you can be authenticated in one click with the link **Login with my Github Account**.
+
+Your name and email are automatically updated from your Github Account if defined.
+
+Installation instructions
+-------------------------
+
+### Setting up OAuth 2.0
+
+- On Github, go to the page [Register a new OAuth application](https://github.com/settings/applications/new)
+- Just follow the [official Github documentation](https://developer.github.com/guides/basics-of-authentication/#registering-your-app)
+- In Kanboard, you can get the **callback url** in **Settings > Integrations > Github Authentication**
+
+### Setting up Kanboard
+
+Either create a new `config.php` file or rename the `config.default.php` file and set the following values:
+
+```php
+// Enable/disable Github authentication
+define('GITHUB_AUTH', true);
+
+// Github client id (Copy it from your settings -> Applications -> Developer applications)
+define('GITHUB_CLIENT_ID', 'YOUR_GITHUB_CLIENT_ID');
+
+// Github client secret key (Copy it from your settings -> Applications -> Developer applications)
+define('GITHUB_CLIENT_SECRET', 'YOUR_GITHUB_CLIENT_SECRET');
+```
+
+### Github Entreprise
+
+To use this authentication method with Github Enterprise you have to change the default urls.
+
+Replace these values by your self-hosted instance of Github:
+
+```php
+// Github oauth2 authorize url
+define('GITHUB_OAUTH_AUTHORIZE_URL', 'https://github.com/login/oauth/authorize');
+
+// Github oauth2 token url
+define('GITHUB_OAUTH_TOKEN_URL', 'https://github.com/login/oauth/access_token');
+
+// Github API url (don't forget the slash at the end)
+define('GITHUB_API_URL', 'https://api.github.com/');
+```
+
+Notes
+-----
+
+Kanboard uses these information from your public Github profile:
+
+- Full name
+- Public email address
+- Github unique id
+
+The Github unique id is used to link the local user account and the Github account.