> ## Documentation Index
> Fetch the complete documentation index at: https://docs.fucksornot.com/llms.txt
> Use this file to discover all available pages before exploring further.

# OAuth Authentication

> Sign in with Google, Apple, or Meta

FoN supports OAuth 2.0 authentication with major providers.

## Supported Providers

| Provider | Initiation Endpoint          | Callback Endpoint               |
| -------- | ---------------------------- | ------------------------------- |
| Google   | `GET /api/auth/oauth/google` | `GET /api/auth/callback/google` |
| Apple    | `GET /api/auth/oauth/apple`  | `GET /api/auth/callback/apple`  |
| Meta     | `GET /api/auth/oauth/meta`   | `GET /api/auth/callback/meta`   |

## OAuth Flow

OAuth authentication follows the standard flow:

<Steps>
  <Step title="Initiate OAuth">
    Redirect the user to the OAuth initiation endpoint:

    ```
    https://fucksornot.com/api/auth/oauth/google
    ```
  </Step>

  <Step title="User Authenticates">
    User authenticates with the OAuth provider (Google, Apple, or Meta)
  </Step>

  <Step title="Callback">
    Provider redirects back to FoN's callback endpoint with authorization code
  </Step>

  <Step title="Session Created">
    FoN creates a session and redirects to the application with authentication cookie set
  </Step>
</Steps>

## Implementation

### Web Applications

For web applications, simply link to the OAuth endpoint:

```html theme={null}
<a href="https://fucksornot.com/api/auth/oauth/google">
  Sign in with Google
</a>
```

### Single Page Applications

For SPAs, open a popup or redirect:

```javascript theme={null}
// Popup method
const popup = window.open(
  'https://fucksornot.com/api/auth/oauth/google',
  'oauth',
  'width=500,height=600'
);

// Listen for the popup to close
const interval = setInterval(() => {
  if (popup.closed) {
    clearInterval(interval);
    // Check authentication status
    checkAuth();
  }
}, 1000);
```

### Mobile Applications

For mobile apps, use a webview or in-app browser:

```javascript theme={null}
// React Native example with expo-web-browser
import * as WebBrowser from 'expo-web-browser';

const signInWithGoogle = async () => {
  const result = await WebBrowser.openAuthSessionAsync(
    'https://fucksornot.com/api/auth/oauth/google',
    'your-app://callback'
  );
};
```

## After OAuth

After successful OAuth authentication:

1. A session is created on FoN
2. An `auth-token` cookie is set
3. The user is redirected to your application

Use the [Check Status](/api-reference/auth/check-status) endpoint to verify authentication:

```bash theme={null}
curl https://fucksornot.com/api/auth/check \
  --cookie "auth-token=..."
```

## Notes

* OAuth creates or links to a FoN account
* If the OAuth email matches an existing account, it's linked
* Users can have multiple OAuth providers linked to one account
* MFA can still be enabled alongside OAuth