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Accept-Encoding 'gzip' to make your cralwer faster

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If you are looking for a way to make your web crawler / spider work faster, then you must be looking for reducing the time to fetch data from the Internet. Fortunately many websites provide the content in compressed format if the server gets such type of request. If you see the request header of Firefox (you can use firebug to see the request / response headers), you can find that it always asks for gzip content. If the server provides gzip, then it sends data in gzip form otherwise it sends html. gzip data reduces bandwidth and thus make the program to scrape / harvest data faster. So you can do the same from you Python code. Just add ('Accept-Encoding', 'gzip,deflate') in the request header. Check the following code chunk: opener = urllib2.build_opener() opener.addheaders = [('Referer', referer), ('User-Agent', uagent), ('Accept-Encoding', 'gzip,deflate')] usock = opener.open(url) url = usock.geturl() data = decode(usock) usock.c...
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Strip HTML tags using Python

We often need to strip HTML tags from string (or HTML source). I usually do it using a simple regular expression in Python. Here is my function to strip HTML tags: def remove_html_tags(data): p = re.compile(r'<.*?>') return p.sub('', data) Here is another function to remove more than one consecutive white spaces: def remove_extra_spaces(data): p = re.compile(r'\s+') return p.sub(' ', data) Note that re module needs to be imported in order to use regular expression. Here you can find an updated code that gets the text from html: http://love-python.blogspot.com/2011/04/html-to-text-in-python.html
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Python all any built-in function

I have been using Python for a long time, still learning lot of simple and new things. Recently I came to know about two built-in functions named all and any . Today while I was solving a hackerrank problem , I used both functions which makes the code a bit nicer, in my opinion. The functions compares two singly linked lists and if they are equal, returns 1, otherwise returns 0. Here is my code - def compare_lists(llist1, llist2): while all([llist1, llist2]): if llist1.data != llist2.data: return 0 llist1 = llist1.next llist2 = llist2.next if any([llist1, llist2]): return 0 return 1 Sometimes, this kind of simple thing brings joy to me. Let me know your thoughts. :)
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