这种模式，就是将一个最终对象分级分层建造出来。
在软件发布过程中，不同的JAVA,PYTHON,NODE.JS,ZIP压缩包，
就可以使用不同的阶段来使用建造者模式的。
from enum import Enum
import time
PizzaProgress = Enum('PizzaProgress', 'queued preparation baking ready')
PizzaDough = Enum('PizzaDough', 'thin thick')
PizzaSauce = Enum('PizzaTopping', 'tomato creme_fraiche')
PizzaTopping = Enum('PizzaTopping', 'mozzaralla double_mozzarella bacon ham mushrooms red_onion oregano')
STEP_DELAY = 3
class Pizza:
def __init__(self, name):
self.name = name
self.dough = None
self.sauce = None
self.topping = []
def __str__(self):
return self.name
def prepare_dough(self, dough):
self.dough = dough
print('preparing the {} dough of your {}...'.format(self.dough.name, self))
time.sleep(STEP_DELAY)
print('done with the {} dough'.format(self.dough.name))
class MargaritaBuilder:
def __init__(self):
self.pizza = Pizza('margarita')
self.progress = PizzaProgress.queued
self.baking_time = 5
def prepare_dough(self):
self.progress = PizzaProgress.preparation
self.pizza.prepare_dough(PizzaDough.thin)
def add_sauce(self):
print('adding the tomato sauce to your margarita...')
self.pizza.sauce = PizzaSauce.tomato
time.sleep(STEP_DELAY)
print('done with the tomato sauce')
def add_topping(self):
print('adding the topping (double mozzarella, oregano) to your margarita')
self.pizza.topping.append([i for i in
(PizzaTopping.double_mozzarella, PizzaTopping.oregano)])
time.sleep(STEP_DELAY)
print('done with the topping (double mozzarrella, oregano)')
def bake(self):
self.progress = PizzaProgress.baking
print('baking your margarita for {} seconds'.format(self.baking_time))
time.sleep(self.baking_time)
self.progress = PizzaProgress.ready
print('your margarita is ready')
class CreamyBaconBuilder:
def __init__(self):
self.pizza = Pizza('creamy bacon')
self.progress = PizzaProgress.queued
self.baking_time = 7
def prepare_dough(self):
self.progress = PizzaProgress.preparation
self.pizza.prepare_dough(PizzaDough.thick)
def add_sauce(self):
print('adding the creme fraiche sauce to you creamy bacon')
self.pizza.sauce = PizzaSauce.creme_fraiche
time.sleep(STEP_DELAY)
print('done with the creme fraiche sauce')
def add_topping(self):
print('adding the topping (mozzaralla, bacon, ham, mushrooms, red onion, oregano) to you creamy bacon')
self.pizza.topping.append([t for t in
(PizzaTopping.mozzaralla, PizzaTopping.bacon,
PizzaTopping.ham, PizzaTopping.mushrooms,
PizzaTopping.red_onion, PizzaTopping.oregano)])
time.sleep(STEP_DELAY)
print('done with the topping(mozzarella, bacon, ham, mushrooms, red onion, oregano)')
def bake(self):
self.progress = PizzaProgress.baking
print('baking your creamy bacon for {} seconds'.format(self.baking_time))
time.sleep(self.baking_time)
self.progress = PizzaProgress.ready
print('your creamy bacon is ready')
class Waiter:
def __init__(self):
self.buider = None
def construct_pizza(self, builder):
self.builder = builder
[step() for step in (builder.prepare_dough,
builder.add_sauce, builder.add_topping, builder.bake)]
@property
def pizza(self):
return self.builder.pizza
def validate_style(builders):
try:
pizza_style = input('What pizza would you like, [m]argarita or [c]reamy bacon,')
builder = builders[pizza_style]()
valid_input = True
except KeyError as err:
print('Sorry , only margarita (key m) and creamy bacon (key c) are available')
return (False, None)
return (True, builder)
def main():
builders = dict(m=MargaritaBuilder, c=CreamyBaconBuilder)
valid_input = False
while not valid_input:
valid_input, builder = validate_style(builders)
print()
waiter = Waiter()
waiter.construct_pizza(builder)
pizza = waiter.pizza
print()
print('Enjoy your {}!'.format(pizza))
if __name__ == '__main__':
main()
