Behat Screenshot Image Driver Dummy Laravel Package

Getting Started

Minimal Setup

1. Install the Package Add to your composer.json under require-dev:

   composer require --dev bex/behat-screenshot-image-driver-dummy
   

2. Configure behat.yml Enable the dummy driver in the Bex\Behat\ScreenshotExtension config:

   default:
     extensions:
       Bex\Behat\ScreenshotExtension:
         active_image_drivers: dummy
   

3. First Use Case Run a failing Behat scenario. The extension will generate a dummy image URL (e.g., http://docs.behat.org/en/v2.5/_static/img/logo.png) instead of saving an actual screenshot. Useful for:

   • Local testing without external dependencies (e.g., no need for imagick/gd).
   • Mocking screenshots in CI/CD pipelines where real screenshots aren’t needed.

Implementation Patterns

Workflow Integration

1. Replace Real Drivers for Testing Use the dummy driver in behat.yml for environments where screenshots aren’t required (e.g., unit tests, CI):

   # behat.yml (test environment)
   extensions:
     Bex\Behat\ScreenshotExtension:
       active_image_drivers: dummy
       screenshot_directory: null  # Disable saving files
   

2. Conditional Driver Switching Dynamically enable/disable the dummy driver via environment variables or PHP config:

   // In a custom Behat extension or bootstrap
   if (app()->environment('testing')) {
       $config['extensions']['Bex\Behat\ScreenshotExtension']['active_image_drivers'] = ['dummy'];
   }
   

3. Extend for Custom Dummy Logic Override the dummy URL or behavior by creating a custom driver (see Gotchas for extension points).

Laravel-Specific Tips

• Service Provider Integration Bind the dummy driver to Laravel’s container for dynamic configuration:

  // app/Providers/BehatServiceProvider.php
  public function register()
  {
      $this->app->singleton('behat.screenshot.driver.dummy', function () {
          return new \Bex\Behat\Screenshot\ImageDriver\DummyDriver();
      });
  }
  

• Artisan Command Hooks Use the dummy driver in custom Artisan commands to simulate screenshot failures:

  // app/Console/Commands/TestBehatScreenshot.php
  public function handle()
  {
      $this->call('behat', [
          '--config' => 'behat-dummy.yml', // Uses dummy driver
      ]);
  }
  

Gotchas and Tips

Pitfalls

1. Outdated Dependencies

   • The package was last updated in 2015 and targets bex/behat-screenshot (likely v1.x). Ensure compatibility with your Behat version (v3.x+ may require adjustments).
   • Fix: Fork the repo and update the Bex\Behat\ScreenshotExtension namespace if needed.

2. No Real Screenshot Logic

   • The dummy driver only returns a hardcoded URL (e.g., Behat’s logo). If you need dynamic placeholders (e.g., base64-encoded images), extend the driver:

     // app/Behat/DummyDriver.php
     namespace App\Behat;
     
     use Bex\Behat\Screenshot\ImageDriver\DummyDriver as BaseDummyDriver;
     
     class DummyDriver extends BaseDummyDriver
     {
         public function getImageUrl()
         {
             return 'data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAA...';
         }
     }
     

   • Register it in behat.yml:

     active_image_drivers: ['App\Behat\DummyDriver']
     

3. CI/CD False Positives

   • The dummy URL may trigger unnecessary alerts in CI if logs aren’t filtered. Use expectOutput() in PHPUnit to ignore it:

     $this->expectOutputToContain('Screenshot has been taken');
     

Debugging

• Verify Driver Activation Check if the driver is loaded by inspecting Behat’s output. If the URL doesn’t change, the driver isn’t active.

  • Debug: Add this to your FeatureContext:

    use Bex\Behat\ScreenshotExtension\ScreenshotExtension;
    public function __construct() {
        $this->getModule(ScreenshotExtension::class)->getImageDriver();
    }
    

• Log Driver Calls Extend the driver to log invocations:

  class DebugDummyDriver extends BaseDummyDriver {
      public function getImageUrl() {
          \Log::debug('Dummy driver called!');
          return parent::getImageUrl();
      }
  }
  

Extension Points

1. Custom Dummy URLs Override getImageUrl() in a child class to return dynamic URLs (e.g., from a Laravel view):

   public function getImageUrl()
   {
       return route('behat.dummy.image');
   }
   

2. Mock File System Combine with Laravel’s Storage facade to simulate screenshot paths:

   public function saveScreenshot($image, $path)
   {
       Storage::disk('local')->put($path, $image);
       return 'storage/' . $path; // Return a fake path
   }
   

3. Integration with Laravel Testing Use in phpunit.xml to skip screenshot steps in tests:

   <env name="BEHAT_SCREENSHOT_DRIVER" value="dummy"/>