HTTP – Parse HTML and XHTML

In this article you will learn how to parse the HTML (HyperText Mark-up Language) of a website. There are several Python libraries to achieve that. We will give a demonstration of a few popular ones.

Beautiful Soup – a python package for parsing HTML and XML
This library is very popular and can even work with malformed markup. To get the contents of a single div, you can use the code below:

from BeautifulSoup import BeautifulSoup
import urllib2
 
 
# get the contents
response = urllib2.urlopen('http://en.wikipedia.org/wiki/Python_(programming_language)')
html = response.read()
 
parsed_html = BeautifulSoup(html)
print parsed_html.body.find('div', attrs={'class':'toc'})

This will output the HTML code of within the div called ‘toc’ (table of contents) of the wikipedia article. If you want only the raw text use:

print parsed_html.body.find('div', attrs={'class':'toc'}).text

If you want to get the page title, you need to get it from the head section:

print parsed_html.head.find('title').text

To grab all images URLs from a website, you can use this code:

from BeautifulSoup import BeautifulSoup
import urllib2
 
url = 'http://www.arstechnica.com/'
data = urllib2.urlopen(url).read()
soup = BeautifulSoup(data)
links = soup.findAll('img', src=True)
 
for link in links:
    print(link["src"])

To grab all URLs from the webpage, use this:

from BeautifulSoup import BeautifulSoup
import urllib2
 
url = 'http://www.arstechnica.com/'
data = urllib2.urlopen(url).read()
soup = BeautifulSoup(data)
links = soup.findAll('a')
 
for link in links:
    print(link["href"])

PyQuery – a jquery like library for Python
To extract data from the tags we can use PyQuery. It can grab the actual text contents and the html contents, depending on what you need. To grab a tag you use the call pq(‘tag’).

from pyquery import PyQuery    
import urllib2
response = urllib2.urlopen('http://en.wikipedia.org/wiki/Python_(programming_language)')
 
html = response.read()
pq = PyQuery(html)
tag = pq('div#toc')
 
# print the text of the div
print tag.text()
 
# print the html of the div
print tag.html()

To get the title simply use:

tag = pq('title')

HTMLParser – Simple HTML and XHTML parser
The usage of this library is very different. With this library you have to put all your logic in the WebParser class. A basic example of usage below:

from HTMLParser import HTMLParser
import urllib2
 
# create parse
class WebParser(HTMLParser):
    def handle_starttag(self, tag, attrs):
        print "Tag: " + tag
 
# get the contents
response = urllib2.urlopen('http://en.wikipedia.org/wiki/Python_(programming_language)')
html = response.read()
 
# instantiate the parser and fed it some HTML
parser = WebParser()
parser.feed(html)

HTTP – Parse HTML and XHTML

2 thoughts on “HTTP – Parse HTML and XHTML”

Leave a Reply Cancel reply