Is Goutte compliant with robots.txt rules on websites?

Goutte is a screen scraping and web crawling library for PHP. When using Goutte, or any other scraping tool, it's important to respect the rules set out in the robots.txt file of the target website. The robots.txt file is used by website administrators to communicate with web crawlers and indicate which parts of the site should not be accessed or indexed by bots.

Goutte itself does not automatically comply with robots.txt rules. It's the responsibility of the developer using Goutte to check the robots.txt file of the target website and ensure that their scraping activities are compliant with the rules specified therein.

To comply with robots.txt rules while using Goutte, you should:

1. Fetch and parse the robots.txt file from the target website.
2. Interpret the rules in the robots.txt file to understand which paths are disallowed for your user agent.
3. Modify your scraping logic in Goutte accordingly to avoid disallowed paths.

Here's a general example of how you might programmatically check robots.txt rules in PHP before using Goutte to scrape a site (note that this is a simplified example and does not handle all possible robots.txt directives):

<?php

require 'vendor/autoload.php';

use Goutte\Client;

// User agent string for your web crawler
$userAgent = 'MyWebCrawler/1.0';

// Base URL of the target website
$baseUrl = 'https://example.com';

// Fetch the robots.txt file from the target website
$robotsTxt = file_get_contents($baseUrl . '/robots.txt');

// Parse the robots.txt file to check if crawling is allowed for your user agent
$lines = explode("\n", $robotsTxt);
$disallowPaths = [];
$userAgentMatched = false;

foreach ($lines as $line) {
    $line = trim($line);

    if (strpos($line, 'User-agent: ') === 0) {
        $ua = substr($line, strlen('User-agent: '));
        if ($ua === '*' || $ua === $userAgent) {
            $userAgentMatched = true;
        } else {
            $userAgentMatched = false;
        }
    }

    if ($userAgentMatched && strpos($line, 'Disallow: ') === 0) {
        $disallowPaths[] = trim(substr($line, strlen('Disallow: ')));
    }
}

// Now use Goutte to scrape content, respecting the disallowed paths
$client = new Client();

$crawler = $client->request('GET', $baseUrl);

// Your scraping logic here
// Make sure to check if the path you want to scrape is not in the $disallowPaths array

This example is quite rudimentary. A real-world implementation should handle all directives in the robots.txt file, account for wildcard characters, and consider the Allow directive as well. There also exist libraries and tools that can handle robots.txt parsing for you, which could be more robust and easier to use.

Always remember, even if you comply with robots.txt, the website owner might have other terms of use that restrict scraping. It's essential to read and understand those terms before proceeding with any scraping activities.