Question

Does Python have screen scraping libraries that offer JavaScript support?

I’ve been using pycurl for simple HTML requests, and Java’s HtmlUnit for more complicated requests requiring JavaScript support.

Ideally I would like to be able to do everything from Python, but I haven’t come across any libraries that would allow me to do it. Do they exist?

Answer 1

There are many options when dealing with static HTML, which the other responses cover. However if you need JavaScript support and want to stay in Python I recommend using webkit to render the webpage (including the JavaScript) and then examine the resulting HTML. For example:

import sys
import signal
from PyQt4.QtCore import *
from PyQt4.QtGui import *
from PyQt4.QtWebKit import QWebPage

class Render(QWebPage):
    def __init__(self, url):
        self.app = QApplication(sys.argv)
        QWebPage.__init__(self)
        self.html = None
        signal.signal(signal.SIGINT, signal.SIG_DFL)
        self.connect(self, SIGNAL('loadFinished(bool)'), self._finished_loading)
        self.mainFrame().load(QUrl(url))
        self.app.exec_()

    def _finished_loading(self, result):
        self.html = self.mainFrame().toHtml()
        self.app.quit()


if __name__ == '__main__':
    try:
        url = sys.argv[1]
    except IndexError:
        print 'Usage: %s url' % sys.argv[0]
    else:
        javascript_html = Render(url).html