A sha1sum check for file URL

url_sha1sum.py

#!/usr/bin/env python
# -*- coding: utf-8 -*-
""" File download check """

__author__ = "Clayton Kramer"
__copyright__ = "Copyright 2014"
__credits__ = ["Clayton Kramer"]
__license__ = "GPL"
__version__ = "1.0.1"
__maintainer__ = "Rob Knight"
__email__ = "clayton.kramer <at> gmail.com"
__status__ = "Production"

import urllib2
import hashlib
import optparse


def url_sha1sum(url):
    """
    Download a file from a URL and return a sha1sum of it.

    :param url:
    """
    response = urllib2.urlopen(url)
    pdf = response.read()
    response.close()
    return hashlib.sha1(pdf).hexdigest()


if __name__ == '__main__':
    desc = 'This is a file download check tool.'

    parser = optparse.OptionParser(
        description=desc,
        version='%prog {}'.format(__version__),
        usage='Usage: %prog <options> url'
    )
    parser.add_option(
        '-t', '--test', action='store',
        dest='test', help='sha1sum test value'
    )
    parser.add_option(
        '-n', '--noop', action='store_true',
        dest='noop', help='No sha1 check. Returns sha1sum of URL.'
    )
    opts, args = parser.parse_args()

    if len(args) < 1:
        parser.print_help()
        exit(-1)

    file_url = None
    try:
        file_url = args[0]
    except IndexError:
        parser.error('URL argument missing')
        exit(-1)

    if opts.noop:
        print url_sha1sum(file_url)
        exit()

    if opts.test is None:
        print "Error: No sha1sum test string provided."
        parser.print_help()
        exit(-1)
    else:
        if url_sha1sum(file_url) == opts.test:
            print 1
        else:
            print 0
        exit()