How do I handle file downloads during web scraping with Symfony Panther?

Symfony Panther is a browser testing and web scraping library for PHP that leverages the WebDriver protocol. It allows you to control browsers like Chrome and Firefox programmatically. When it comes to handling file downloads during web scraping with Panther, there are a few steps you need to follow.

Panther doesn't have a built-in method to directly handle file downloads. However, you can configure the browser client to download files to a specific directory and then use PHP to interact with the downloaded files. Here's a step-by-step guide on how to accomplish this:

1. Configure the Client for Downloading

When initializing the Panther client, you can configure Chrome to automatically download files to a specified directory without user interaction.

use Symfony\Component\Panther\PantherTestCase;

class MyPantherTest extends PantherTestCase
{
    public function setUp(): void
    {
        parent::setUp();

        // Set download path for Chrome
        $this->client = static::createPantherClient([
            'webServerDir' => __DIR__.'/../../public', // adjust the path to your public directory
            'browser' => static::CHROME,
        ]);

        $this->client->getWebDriver()->manage()->addCookie([
            'name' => 'download.default_directory',
            'value' => '/path/to/download/directory', // provide the absolute path
            'domain' => 'localhost', // adjust as needed
        ]);
    }

    public function testFileDownload()
    {
        // Your scraping logic here
    }
}

2. Trigger the Download

During the scraping process, you'll usually encounter a download link or button. You can use Panther's crawler to click on the element that triggers the file download.

// Assuming you have the link to the file you want to download
$fileDownloadLink = 'http://example.com/download-file';

// Navigate to the download link
$this->client->request('GET', $fileDownloadLink);

// If the download is triggered by clicking a button, find the button and click it
$downloadButton = $this->client->getCrawler()->selectButton('Download');
$downloadButton->click();

3. Wait for the Download to Complete

After triggering the download, you should wait for the download to complete before proceeding. You can do this by checking the download directory for the presence of the file.

$downloadPath = '/path/to/download/directory';
$fileName = 'downloaded_file.pdf'; // Expected file name

// Wait for the file to appear in the download directory
while (!file_exists($downloadPath.'/'.$fileName)) {
    sleep(1); // You can adjust the sleep time or implement a more sophisticated waiting mechanism
}

// Now the file should be in the download directory

4. Interact with the Downloaded File

Once the file is downloaded, you can perform whatever operation you need on it, such as reading its contents, moving it to another directory, or processing it as required by your application.

// Read the downloaded file
$fileContent = file_get_contents($downloadPath.'/'.$fileName);

// Process the content as needed

Note

Please keep in mind that when working with Symfony Panther, you're dealing with a real browser in a real environment, so file downloads will work the same way as if you were manually clicking and saving files. However, this also means you need to ensure that your script has the necessary permissions to write to the download directory and handle files accordingly.

Remember to configure the download path correctly for the browser you are using, and adjust the domain and other parameters as necessary. Always test your setup thoroughly to ensure that the file downloads and subsequent file handling are working as expected.