box-o-sand/src/02-shipping/shipping.py

from __future__ import print_function

import sys
import cgi
from wsgiref.simple_server import make_server


def main(sysargs=sys.argv[:]):
    port = 18080
    server = make_server('0.0.0.0', port, shipping_app)
    print('serving {0.__name__} on port {1}'.format(shipping_app, port))
    server.serve_forever()
    return 0


def shipping_app(environ, start_response):
    path_info = environ.get('PATH_INFO', '').strip('/')

    handler = {
        'text': plaintext_handler,
        'xml': xml_handler,
    }.get(path_info)

    if handler:
        try:
            return handler(environ, start_response)
        except Exception:
            start_response('500 Internal Server Error', [
                ('content-type', 'text/plain'),
            ])
            return ['OUCH']
    else:
        ret = 'nothin at {0!r}'.format(path_info)
        start_response('404 Not Found', [
            ('content-type', 'text/plain'),
            ('content-length', str(len(ret)))
        ])
        return [ret]


def get_params(environ):
    params = cgi.parse(fp=environ.get('wsgi.input'), environ=environ)
    for key, value in params.iteritems():
        if len(value) == 1:
            params[key] = value[0]
    return params


def xml_handler(environ, start_response):
    params = get_params(environ)
    zipcode = int(params.get('zipcode', 0))
    pounds = int(params.get('pounds', 0))

    ret = ['<options>']
    for service, price in get_shipping_options(zipcode, pounds).iteritems():
        ret.append('<option><service>{service}</service>'
                   '<price>{price}</price></option>'.format(**locals()))
    ret.append('</options>')
    body = '\n'.join(ret)

    start_response('200 OK', [
        ('content-type', 'text/xml'),
        ('content-length', str(len(body)))
    ])
    return [body]


def plaintext_handler(environ, start_response):
    params = get_params(environ)
    zipcode = int(params.get('zipcode', 0))
    pounds = int(params.get('pounds', 0))

    ret = []
    for service, price in get_shipping_options(zipcode, pounds).iteritems():
        ret.append('{service}: {price} USD'.format(**locals()))
    body = '\n'.join(ret)

    start_response('200 OK', [
        ('content-type', 'text/plain'),
        ('content-length', str(len(body)))
    ])
    return [body]


def get_shipping_options(zipcode, pounds):
    base_cost = (float(zipcode) / 10000.0) + (pounds * 5.0)
    return {
        "Next Day": int(base_cost * 4),
        "Two Day Air": int(base_cost * 2),
        "Saver Ground": int(base_cost)
    }


if __name__ == '__main__':
    sys.exit(main())

# vim:filetype=python