def test_create_invalid_return(self):
        """
        catch and handle bogus requests (ex. faveicon)
        """
        status, response_headers, response_body = create_invalid_return()

        self.assertEqual(status, '404 NOT FOUND')
        self.assertEqual(response_body, '')

        self.assertEqual(response_headers[0][0], 'Content-Type')
        self.assertEqual(response_headers[0][1], 'application/json')
        self.assertEqual(response_headers[1][0], 'Content-Length')
        self.assertEqual(response_headers[1][1], '0')
def application(environ, start_response):
    """
    The wsgi callback
    """
    try:
        # catch and handle bogus requests (ex. faveicon)
        valid = valid_request(environ)
        if not valid:
            status, response_headers, response_body = create_invalid_return()
            start_response(status, response_headers)
            return [response_body]

        # get the index range and index mode from the query string
        id_range, id_mode = range_and_mode(environ)

        # get the new unique end index
        if id_range and id_mode:
            UniqueIndex.database_connect()
            index, id_range = update_index(id_range, id_mode)
            UniqueIndex.database_close()
            if index and id_range:
                # create the response with start and end indices
                status, response_headers, response_body = create_valid_return(index, id_range)

                # send it back to the requestor
                start_response(status, response_headers)
                return [response_body]

        # something bad
        status, response_headers, response_body = create_invalid_return()
        start_response(status, response_headers)
        return [response_body]
    except peewee.OperationalError, ex:
        peewee_logger = logging.getLogger("peewee")
        peewee_logger.setLevel(logging.DEBUG)
        peewee_logger.addHandler(logging.StreamHandler())
        peewee_logger.warn("OperationalError(%s)", str(ex))