Grab

What is Grab?

Grab is a python web scraping framework. Grab provides a number of helpful methods to perform network requests, scrape web sites and process the scraped content:

Automatic cookies (session) support
HTTP and SOCKS proxy with/without authorization
Keep-Alive support
IDN support
Tools to work with web forms
Easy multipart file uploading
Flexible customization of HTTP requests
Automatic charset detection
Powerful API to extract data from DOM tree of HTML documents with XPATH queries
Asynchronous API to make thousands of simultaneous queries. This part of library called Spider. See list of spider fetures below.
Python 3 ready

Spider is a framework for writing web-site scrapers. Features:

Rules and conventions to organize the request/parse logic in separate blocks of codes
Multiple parallel network requests
Automatic processing of network errors (failed tasks go back to task queue)
You can create network requests and parse responses with Grab API (see above)
HTTP proxy support
Caching network results in permanent storage
Different backends for task queue (in-memory, redis, mongodb)
Tools to debug and collect statistics

Grab Example

import logging

from grab import Grab

logging.basicConfig(level=logging.DEBUG)

g = Grab()

g.go('https://github.com/login')
g.doc.set_input('login', '****')
g.doc.set_input('password', '****')
g.doc.submit()

g.doc.save('/tmp/x.html')

g.doc('//ul[@id="user-links"]//button[contains(@class, "signout")]').assert_exists()

home_url = g.doc('//a[contains(@class, "header-nav-link name")]/@href').text()
repo_url = home_url + '?tab=repositories'

g.go(repo_url)

for elem in g.doc.select('//h3[@class="repo-list-name"]/a'):
    print('%s: %s' % (elem.text(),
                      g.make_url_absolute(elem.attr('href'))))

Grab::Spider Example

import logging

from grab.spider import Spider, Task

logging.basicConfig(level=logging.DEBUG)


class ExampleSpider(Spider):
    def task_generator(self):
        for lang in 'python', 'ruby', 'perl':
            url = 'https://www.google.com/search?q=%s' % lang
            yield Task('search', url=url, lang=lang)

    def task_search(self, grab, task):
        print('%s: %s' % (task.lang,
                          grab.doc('//div[@class="s"]//cite').text()))


bot = ExampleSpider(thread_number=2)
bot.run()

Installation

$ pip install -U grab

See details about installing Grab on different platforms here http://docs.grablib.org/en/latest/usage/installation.html

Documentation and Help

Documentation: http://docs.grablib.org/en/latest/

Mailing list (mostly russian): http://groups.google.com/group/python-grab/

Contribution

To report a bug please use GitHub issue tracker: https://github.com/lorien/grab/issues

If you want to develop new feature in Grab please use issue tracker to describe what you want to do or contact me at lorien@lorien.name