python-patterns/mvc.py

#!/usr/bin/env python
# -*- coding: utf-8 -*-


class Model(object):

    products = {
        'milk': {'price': 1.50, 'quantity': 10},
        'eggs': {'price': 0.20, 'quantity': 100},
        'cheese': {'price': 2.00, 'quantity': 10}
    }


class View(object):

    def product_list(self, product_list):
        print('PRODUCT LIST:')
        for product in product_list:
            print(product)
        print('')

    def product_information(self, product, product_info):
        print('PRODUCT INFORMATION:')
        print('Name: %s, Price: %.2f, Quantity: %d\n' %
              (product.title(), product_info.get('price', 0),
               product_info.get('quantity', 0)))

    def product_not_found(self, product):
        print('That product "%s" does not exist in the records' % product)


class Controller(object):

    def __init__(self):
        self.model = Model()
        self.view = View()

    def get_product_list(self):
        product_list = self.model.products.keys()
        self.view.product_list(product_list)

    def get_product_information(self, product):
        product_info = self.model.products.get(product, None)
        if product_info is not None:
            self.view.product_information(product, product_info)
        else:
            self.view.product_not_found(product)


if __name__ == '__main__':

    controller = Controller()
    controller.get_product_list()
    controller.get_product_information('cheese')
    controller.get_product_information('eggs')
    controller.get_product_information('milk')
    controller.get_product_information('arepas')

### OUTPUT ###
# PRODUCT LIST:
# cheese
# eggs
# milk
#
# PRODUCT INFORMATION:
# Name: Cheese, Price: 2.00, Quantity: 10
#
# PRODUCT INFORMATION:
# Name: Eggs, Price: 0.20, Quantity: 100
#
# PRODUCT INFORMATION:
# Name: Milk, Price: 1.50, Quantity: 10
#
# That product "arepas" does not exist in the records