Google Page Rank Python Script

This isn’t my script but I thought it would appeal to the reader of this blog.  It’s a script that  will lookup the Google Page Rank for any website and uses the same interface as the Google Toolbar to do it. I’d like to thank Fred Cirera for writing it and you can checkout his blog about this script here.

I’m not exactly sure what I would use this for but it might have applications for anyone who wants to do some really advanced SEO work and find a real way to accomplish Page Rank sculpting. Perhaps finding the best websites to put links on.

The reason it is such an involved bit of math is that it need to compute a checksum in order to work. It should be pretty reliable since it doesn’t involve and scraping.

Example usage:

$ python pagerank.py http://www.google.com/
PageRank: 10	URL: http://www.google.com/

$ python pagerank.py http://www.mozilla.org/
PageRank: 9	URL: http://www.mozilla.org/

$ python pagerank.py http://halotis.com
PageRange: 3   URL: http://www.halotis.com/

And the script:

#!/usr/bin/env python
#
#  Script for getting Google Page Rank of page
#  Google Toolbar 3.0.x/4.0.x Pagerank Checksum Algorithm
#
#  original from http://pagerank.gamesaga.net/
#  this version was adapted from http://www.djangosnippets.org/snippets/221/
#  by Corey Goldberg - 2010
#
#  Licensed under the MIT license: http://www.opensource.org/licenses/mit-license.php



import urllib


def get_pagerank(url):
    hsh = check_hash(hash_url(url))
    gurl = 'http://www.google.com/search?client=navclient-auto&features=Rank:&q=info:%s&ch=%s' % (urllib.quote(url), hsh)
    try:
        f = urllib.urlopen(gurl)
        rank = f.read().strip()[9:]
    except Exception:
        rank = 'N/A'
    if rank == '':
        rank = '0'
    return rank
    
    
def  int_str(string, integer, factor):
    for i in range(len(string)) :
        integer *= factor
        integer &= 0xFFFFFFFF
        integer += ord(string[i])
    return integer


def hash_url(string):
    c1 = int_str(string, 0x1505, 0x21)
    c2 = int_str(string, 0, 0x1003F)

    c1 >>= 2
    c1 = ((c1 >> 4) & 0x3FFFFC0) | (c1 & 0x3F)
    c1 = ((c1 >> 4) & 0x3FFC00) | (c1 & 0x3FF)
    c1 = ((c1 >> 4) & 0x3C000) | (c1 & 0x3FFF)

    t1 = (c1 & 0x3C0) < < 4
    t1 |= c1 & 0x3C
    t1 = (t1 << 2) | (c2 & 0xF0F)

    t2 = (c1 & 0xFFFFC000) << 4
    t2 |= c1 & 0x3C00
    t2 = (t2 << 0xA) | (c2 & 0xF0F0000)

    return (t1 | t2)


def check_hash(hash_int):
    hash_str = '%u' % (hash_int)
    flag = 0
    check_byte = 0

    i = len(hash_str) - 1
    while i >= 0:
        byte = int(hash_str[i])
        if 1 == (flag % 2):
            byte *= 2;
            byte = byte / 10 + byte % 10
        check_byte += byte
        flag += 1
        i -= 1

    check_byte %= 10
    if 0 != check_byte:
        check_byte = 10 - check_byte
        if 1 == flag % 2:
            if 1 == check_byte % 2:
                check_byte += 9
            check_byte >>= 1

    return '7' + str(check_byte) + hash_str



if __name__ == '__main__':
    if len(sys.argv) != 2:
        url = 'http://www.google.com/'
    else:
        url = sys.argv[1]

    print get_pagerank(url)