异步调用与回调机制

# 提交任务的俩方式
  #1,同步调用:提交完任务，在原地等待任务执行完毕，拿到结果，再执行下一段代码，导致程序串行执行
import time, random
from concurrent.futures import ThreadPoolExecutor
def la(name):
    print('%s 在拉屎！'%name)
    time.sleep(random.randint(3,5))
    res = random.randint(7, 13) * '#'
    return {'name':name, 'res': res}

def weigh(shit):
    name = shit['name']
    size = len(shit['res'])
    print('%s拉了%skg屎'%(name, size))
if __name__ == '__main__':
    pool = ThreadPoolExecutor(13)
    shit1 = pool.submit(la, 'alex').result()
    print(shit1)
    weigh(shit1)
    shit2 = pool.submit(la, 'wupeqi').result()
    weigh(shit2)
    shit3 = pool.submit(la, 'yuanhao').result()
    weigh(shit3)


  #2,异步调用

import time, random
from concurrent.futures import ThreadPoolExecutor
def la(name):
    print('%s 在拉屎！'%name)
    time.sleep(random.randint(3,5))
    res = random.randint(7, 13) * '#'
    return {'name':name, 'res': res}

def weigh(shit):
    shit = shit.result()
    name = shit['name']
    size = len(shit['res'])
    print('%s拉了%skg屎'%(name, size))
if __name__ == '__main__':
    pool = ThreadPoolExecutor(13)
    shit1 = pool.submit(la, 'alex').add_done_callback(weigh)
    shit2 = pool.submit(la, 'wupeqi').add_done_callback(weigh)
    shit3 = pool.submit(la, 'yuanhao').add_done_callback(weigh)
#add_done_callback(函数)，称为回调机制