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

# OAuth 2.0 Authentication - Google Sheets API for Laravel

> Configure OAuth 2.0 authentication for user-specific Google Sheets access.

OAuth 2.0 authentication allows users to grant your application access to their personal Google Sheets. This method is ideal for user-facing applications where each user manages their own spreadsheets.

## When to Use OAuth 2.0

* **User-centric applications** — Users access their own Google Sheets
* **Multi-tenant applications** — Different users access different spreadsheets
* **Personal data access** — Reading/writing user's personal Google account data
* **Web applications** — Apps where user interaction is available

## Prerequisites

* Google Cloud Console project
* Google Sheets API and Google Drive API enabled
* Laravel Socialite package (recommended)

## Setup Steps

<Steps>
  <Step title="Configure Google Cloud Console">
    1. Go to [Google Cloud Console](https://console.cloud.google.com/)
    2. Select your project or create a new one
    3. Navigate to **APIs & Services** > **Library**
    4. Enable:
       * **Google Sheets API**
       * **Google Drive API**
  </Step>

  <Step title="Create OAuth 2.0 Credentials">
    1. Go to **APIs & Services** > **Credentials**
    2. Click **Create Credentials** > **OAuth client ID**
    3. Configure OAuth consent screen (first time only):
       * Choose **External** for public apps
       * Fill required fields (app name, support email, developer contact)
       * Add scopes: `https://www.googleapis.com/auth/spreadsheets` and `https://www.googleapis.com/auth/drive`
    4. Select **Web application** as application type
    5. Add Authorized Redirect URIs:
       * Development: `http://localhost:8000/auth/google/callback`
       * Production: `https://yourdomain.com/auth/google/callback`
    6. Click **Create**
    7. Copy your **Client ID** and **Client Secret**
  </Step>

  <Step title="Configure Laravel Environment">
    Add to `.env`:

    ```env theme={null}
    GOOGLE_CLIENT_ID=your-client-id-here
    GOOGLE_CLIENT_SECRET=your-client-secret-here
    GOOGLE_REDIRECT=http://localhost:8000/auth/google/callback
    ```

    Update `config/google.php`:

    ```php theme={null}
    'client_id' => env('GOOGLE_CLIENT_ID', ''),
    'client_secret' => env('GOOGLE_CLIENT_SECRET', ''),
    'redirect_uri' => env('GOOGLE_REDIRECT', ''),
    'scopes' => [
        \Google\Service\Sheets::SPREADSHEETS,
        \Google\Service\Drive::DRIVE,
    ],
    'access_type' => 'offline', // Required for refresh tokens
    'prompt' => 'consent select_account',
    ```
  </Step>

  <Step title="Install Laravel Socialite">
    ```bash theme={null}
    composer require laravel/socialite
    ```

    Add to `config/services.php`:

    ```php theme={null}
    'google' => [
        'client_id' => env('GOOGLE_CLIENT_ID'),
        'client_secret' => env('GOOGLE_CLIENT_SECRET'),
        'redirect' => env('GOOGLE_REDIRECT'),
    ],
    ```
  </Step>

  <Step title="Implement OAuth Flow">
    Create an authentication controller:

    ```php theme={null}
    // app/Http/Controllers/AuthController.php
    <?php

    namespace App\Http\Controllers;

    use App\Models\User;
    use Illuminate\Http\Request;
    use Laravel\Socialite\Facades\Socialite;

    class AuthController extends Controller
    {
        public function redirectToGoogle()
        {
            return Socialite::driver('google')
                ->scopes(config('google.scopes'))
                ->with([
                    'access_type' => config('google.access_type'),
                    'prompt' => config('google.prompt'),
                ])
                ->redirect();
        }

        public function handleGoogleCallback()
        {
            try {
                $googleUser = Socialite::driver('google')->user();
                
                $user = User::updateOrCreate(
                    ['email' => $googleUser->email],
                    [
                        'name' => $googleUser->name,
                        'email' => $googleUser->email,
                        'google_access_token' => $googleUser->token,
                        'google_refresh_token' => $googleUser->refreshToken,
                        'google_expires_in' => $googleUser->expiresIn,
                        'google_token_created' => now()->timestamp,
                    ]
                );

                auth()->login($user);

                return redirect('/dashboard')
                    ->with('success', 'Successfully connected to Google!');
            } catch (\Exception $e) {
                return redirect('/login')
                    ->with('error', 'Authentication failed: ' . $e->getMessage());
            }
        }

        public function logout(Request $request)
        {
            auth()->logout();
            $request->session()->invalidate();
            $request->session()->regenerateToken();

            return redirect('/');
        }
    }
    ```
  </Step>

  <Step title="Add Routes">
    ```php theme={null}
    // routes/web.php
    Route::get('/auth/google', [AuthController::class, 'redirectToGoogle'])
        ->name('google.redirect');
    Route::get('/auth/google/callback', [AuthController::class, 'handleGoogleCallback'])
        ->name('google.callback');
    Route::post('/logout', [AuthController::class, 'logout'])
        ->name('logout');
    ```
  </Step>

  <Step title="Update User Model">
    Create migration:

    ```php theme={null}
    // database/migrations/add_google_tokens_to_users_table.php
    Schema::table('users', function (Blueprint $table) {
        $table->text('google_access_token')->nullable();
        $table->text('google_refresh_token')->nullable();
        $table->integer('google_expires_in')->nullable();
        $table->integer('google_token_created')->nullable();
    });
    ```

    Update User model:

    ```php theme={null}
    // app/Models/User.php
    protected $fillable = [
        'name',
        'email',
        'password',
        'google_access_token',
        'google_refresh_token',
        'google_expires_in',
        'google_token_created',
    ];

    protected $hidden = [
        'password',
        'remember_token',
        'google_access_token',
        'google_refresh_token',
    ];

    public function getGoogleTokenArray(): array
    {
        return [
            'access_token' => $this->google_access_token,
            'refresh_token' => $this->google_refresh_token,
            'expires_in' => $this->google_expires_in,
            'created' => $this->google_token_created,
        ];
    }

    public function hasValidGoogleToken(): bool
    {
        return !empty($this->google_access_token) 
            && !empty($this->google_refresh_token);
    }
    ```
  </Step>

  <Step title="Use Sheets with OAuth">
    ```php theme={null}
    use Revolution\Google\Sheets\Facades\Sheets;

    public function getSheetData(Request $request)
    {
        $user = $request->user();
        
        if (!$user->hasValidGoogleToken()) {
            return redirect()->route('google.redirect');
        }

        try {
            $token = $user->getGoogleTokenArray();

            $values = Sheets::setAccessToken($token)
                ->spreadsheet('user-spreadsheet-id')
                ->sheet('Sheet1')
                ->all();
                
            return view('sheets.data', compact('values'));
        } catch (\Exception $e) {
            // Token expired, redirect to re-authenticate
            if (str_contains($e->getMessage(), 'invalid_grant') 
                || str_contains($e->getMessage(), 'unauthorized')) {
                return redirect()->route('google.redirect');
            }

            throw $e;
        }
    }
    ```
  </Step>
</Steps>

## Token Refresh

The package automatically handles token refresh when expired:

```php theme={null}
$token = [
    'access_token' => $user->google_access_token,
    'refresh_token' => $user->google_refresh_token,
    'expires_in' => $user->google_expires_in,
    'created' => $user->google_token_created,
];

// Automatically refreshes if expired
Sheets::setAccessToken($token)
    ->spreadsheet('id')
    ->sheet('Sheet1')
    ->all();

// Get updated token after refresh
$updatedToken = Sheets::getAccessToken();
if ($updatedToken) {
    $user->update([
        'google_access_token' => $updatedToken['access_token'],
        'google_token_created' => time(),
    ]);
}
```

## Middleware

Create middleware to require Google authentication:

```php theme={null}
// app/Http/Middleware/RequireGoogleAuth.php
<?php

namespace App\Http\Middleware;

use Closure;
use Illuminate\Http\Request;

class RequireGoogleAuth
{
    public function handle(Request $request, Closure $next)
    {
        $user = $request->user();

        if (!$user || !$user->hasValidGoogleToken()) {
            if ($request->expectsJson()) {
                return response()->json(
                    ['error' => 'Google authentication required'], 
                    401
                );
            }

            return redirect()->route('google.redirect');
        }

        return $next($request);
    }
}
```

## Security Considerations

### 1. Token Storage

* Store tokens securely in the database
* Use Laravel's built-in encryption
* Never expose tokens in client-side code

### 2. Scope Management

* Only request necessary scopes
* Follow the principle of least privilege
* Clearly explain to users what access you need

### 3. Error Handling

* Handle expired tokens gracefully
* Provide clear re-authentication flows
* Log authentication errors for monitoring

## Troubleshooting

### Common Errors

**"redirect\_uri\_mismatch" error**

* Verify redirect URI in Google Console matches exactly
* Check for http vs https differences
* Verify trailing slashes match

**"invalid\_grant" or "unauthorized" error**

* Token has expired and refresh failed
* Redirect user to re-authenticate
* Check if refresh token is available

**"access\_denied" error**

* User denied permission
* Handle gracefully with appropriate messaging
* Provide option to retry authentication

### Test OAuth Setup

Create a test route to verify your OAuth configuration:

```php theme={null}
Route::get('/test-oauth', function (Request $request) {
    $user = $request->user();
    
    if (!$user->hasValidGoogleToken()) {
        return 'No Google token available. '
            . '<a href="' . route('google.redirect') . '">'
            . 'Authenticate</a>';
    }
    
    try {
        $token = $user->getGoogleTokenArray();
        $sheets = Sheets::setAccessToken($token)->spreadsheetList();
        
        return 'OAuth working! Found ' . count($sheets) 
            . ' spreadsheets.';
    } catch (\Exception $e) {
        return 'OAuth error: ' . $e->getMessage();
    }
})->middleware('auth');
```