在Perl中使用JavaScript支持的Web Crawler？

Question

I want to code a perl application that would crawl some websites and collect images and links from such webpages. Because the most of pages use JavaScript that generate a HTML content, I need to code quasi a client browser with JavaScript support to be able to parse a final HTML code that is generated and/or modified by JavaScript. What are my options?

If possible, please publish some implementation code or link to some example(s).

Answer 1

There are several options.

• Win32::IE::Mechanize on Windows
• Mozilla::Mechanize
• WWW::Mechanize::Firefox
• WWW::Selenium
• Wight

Answer 2

Options that spring to mind:

• You could have Perl use Selenium and have a full-blown browser do the work for you.

• You can download and compile V8 or another open source JavaScript engine and have Perl call an external program to evaluate the JavaScript.

• I don't think Perl's LWP module supports JavaScript, but you might want to check that if you haven't done so already.

Answer 3

WWW :: Scripter与WWW :: Scripter :: Plugin :: JavaScript和WWW :: Scripter :: Plugin :: Ajax插件似乎是最接近你没有使用实际浏览器（模块WWW :: Selenium ， Mozilla） :: Mechanize或Win32 :: IE :: Mechanize使用真正的浏览器）。

Answer 4

Check the complete working example featured in the Scraping pages full of JavaScript . It uses Web::Scraper for HTML processing and Gtk3::WebKit to process dynamic content. However, the later one is quite a PITA to install. If there are not-that-many pages you need to scrape (< 1000), fetching the post-processed DOM content through PhantomJS is an interesting option. I've written the following script for that purpose:

var page = require('webpage').create(),
    system = require('system'),
    fs = require('fs'),
    address, output;

if (system.args.length < 3 || system.args.length > 5) {
    console.log('Usage: phantomjs --load-images=no html.js URL filename');
    phantom.exit(1);
} else {
    address = system.args[1];
    output = system.args[2];
    page.open(address, function (status) {
        if (status !== 'success') {
            console.log('Unable to load the address!');
        } else {
            fs.write(output, page.content, 'w');
        }
        phantom.exit();
    });
}

There's something like that on the CPAN already, it's a module called Wight , but I haven't tested it yet.

Answer 5

WWW :: Mechanize :: Firefox可以与mozrepl一起使用，具有所有javascript操作。