Download some grab.by images into the current directory.

grabme.py

#!/usr/bin/env python

## Download some grab.by images into the current directory.
## Requires curl command-line utility.
##
## The bounds should be given in base62 (e.g. in the range 0 - ZZZZ).
##
## Example:
##
##   mkdir /tmp/grab
##   cd /tmp/grab
##   python /path/to/this/script 1000 1100

import os, sys, re, httplib

alphabet = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ'

def encode(n):
    result = ''
    while n > 0:
        n, r = divmod(n, len(alphabet))
        result = alphabet[r] + result
    return result

def decode(s):
    result = 0
    while len(s) > 0:
        result = result * len(alphabet) + alphabet.find(s[0])
        s = s[1:]
    return result

def grab(start, stop):
    for n in (encode(n) for n in xrange(decode(start), decode(stop))):
        res = get('grab.by', '/%s' % n)
        if res.status == 302:
            print 'Found %s.png' % n
            os.system("curl -Lo %s.png '%s' 2>/dev/null" % (n, res.getheader('Location')))
        else:
            print 'Skipped %s.png (status: %d)' % (n, res.status)

def get(host, url):
    conn = httplib.HTTPConnection('grab.by')
    conn.request('GET', url)
    return conn.getresponse()

def usage():
    print 'usage: python %s start stop' % sys.argv[0]
    sys.exit(1)


def main(start=None, stop=None):
    if not (start and stop):
        usage()
    grab(start, stop)

if __name__ == '__main__':
    main(*sys.argv[1:])