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Using HTMLParser to extract links from html files

We can use python htmllib.HTMLParser to extract link and corresponding text from html files:


import urllib
from formatter import *
from htmllib import *


formatter = AbstractFormatter(NullWriter())
class LinkParser(HTMLParser):
    def __init__(self, *sub, **kw):
        HTMLParser.__init__(self, *sub, **kw)
        self.current_link = self.current_text = None
    def handle_starttag(self, tag, method, attrs):
        if tag == 'a':
            for attr in attrs:
                if attr[0]=='href':
                    self.current_link = attr[1]
        return HTMLParser.handle_starttag(self, tag, method, attrs)
    def handle_endtag(self, tag, method):
        if tag == 'a':
            if self.current_link and self.current_text:
                print self.current_link, self.current_text
            self.current_link = self.current_text = None
        return HTMLParser.handle_endtag(self, tag, method)
    def handle_data(self, data):
        if self.current_link:
            self.current_text = str(data).strip()
        return HTMLParser.handle_data(self, data)

To use the code:

p = LinkParser(formatter)
p.feed(urllib.urlopen('http://www.slashdot.org').read())
p.close()

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