What are the debugging options available in Symfony Panther?

Symfony Panther is a browser testing and web scraping library for PHP that leverages the WebDriver protocol. It provides a way to perform end-to-end testing of your web applications and can also be used to scrape websites. When it comes to debugging, Panther offers several options to help you troubleshoot issues that may arise during the development of your tests or while scraping content.

Here are the debugging options available in Symfony Panther:

1. Screenshots: Panther allows you to take screenshots of the current state of the browser. This is particularly useful to understand what the browser was displaying at the moment when something went wrong.

   $client->takeScreenshot('screenshot.png'); // Saves the screenshot to the specified file

1. Web Inspector: You can inspect the HTML structure and the current state of the DOM by dumping the HTML of the page.

   echo $client->getPageSource(); // Outputs the source of the current page

1. Logging: Panther can be configured to log all the HTTP requests and responses. This is done by setting the PANTHER_NO_HEADLESS environment variable to 1, which will run the browser in a non-headless mode, allowing you to see what's happening in the browser.

   PANTHER_NO_HEADLESS=1 ./bin/phpunit

1. WebDriver Capabilities: You can customize the WebDriver capabilities to include various debugging options. For example, you could enable verbose logging of the WebDriver server.

   $client = \Symfony\Component\Panther\PantherTestCase::createPantherClient([
       'capabilities' => [
           \Facebook\WebDriver\Remote\WebDriverCapabilityType::LOGGING_PREFS => [
               'browser' => 'ALL',
               'driver' => 'ALL',
           ],
       ],
   ]);

1. Environment Variables: Panther supports several environment variables that alter its behavior for debugging purposes, such as PANTHER_ERROR_SCREENSHOT_DIR to specify where to save error screenshots, and PANTHER_NO_HEADLESS to disable headless mode.

   PANTHER_ERROR_SCREENSHOT_DIR=/path/to/screenshots ./vendor/bin/phpunit

1. Profiling: When using Panther with a Symfony application, you can access the Symfony Profiler for more in-depth debugging of your application.

   $profile = $client->getProfile();
   if ($profile) {
       $collector = $profile->getCollector('some_collector_service_id');
       // Analyze collected data
   }

1. Interactive Mode: You can run Panther in a mode that allows you to interact with the browser manually. This can be useful for debugging complex scenarios that require manual intervention to reproduce.

To enable the interactive mode, you can set the PANTHER_NO_HEADLESS environment variable to 1.

1. Error Handling: Panther throws exceptions when it encounters errors. You can catch these exceptions and handle them accordingly in your test or scraping script.

   try {
       $crawler = $client->request('GET', 'http://example.com');
       // Your scraping logic here
   } catch (\Throwable $e) {
       // Handle the error
   }

1. JavaScript Console Output: You can retrieve the browser's console output, including logs, errors, and warnings that may help you debug JavaScript issues.

   $logs = $client->manage()->getLog('browser');
   foreach ($logs as $log) {
       // Process the log entry
   }

By using these debugging options, you can gain better insight into what might be causing issues with your Panther test cases or web scraping scripts. Debugging is essential in any development process, and Panther provides sufficient tools to make this task easier for developers.