'Test the correct params are generated for a canned policy.'

def test_params_canned_policy(self):

    url = 'http://d604721fxaaqy9.cloudfront.net/horizon.jpg?large=yes&license=yes'
    expire_time = 1258237200
    expected_sig = 'Nql641NHEUkUaXQHZINK1FZ~SYeUSoBJMxjdgqrzIdzV2gyEXPDNv0pYdWJkflDKJ3xIu7lbwRpSkG98NBlgPi4ZJpRRnVX4kXAJK6tdNx6FucDB7OVqzcxkxHsGFd8VCG1BkC-Afh9~lOCMIYHIaiOB6~5jt9w2EOwi6sIIqrg_'
    signed_url_params = self.dist._create_signing_params(url, self.pk_id, expire_time, private_key_string=self.pk_str)
    self.assertEqual(3, len(signed_url_params))
    self.assertEqual(signed_url_params['Expires'], '1258237200')
    self.assertEqual(signed_url_params['Signature'], expected_sig)
    self.assertEqual(signed_url_params['Key-Pair-Id'], 'PK123456789754')
