# 一：编写函数，（函数执行的时间是随机的）
# import time
# import random
# def fun1():
# time.sleep(random.randrange(1, 3))
# print(random.randrange(1, 3))
# fun1()
# 二：编写装饰器，为函数加上统计时间的功能
# import time
# import random
# def timer(func):
# # func = fun1
# def wrapper():
# star_time = time.time()
# func()
# stop_time = time.time()
# print('执行时间：%s' % (stop_time - star_time))
# return wrapper
# @timer
# def fun1():
# time.sleep(random.randrange(1, 3))
# print('welcome to the page')
# fun1()
# 三：编写装饰器，为函数加上认证的功能
# import time
# import random
# def check(func):
# '''
# 修饰器：增加认证功能！
# :return:
# '''
# def wrapper(*args,**kwargs):
# usrname=input("Please input your name: ").strip()
# pwd=input("Please input your pwd: ").strip()
# if usrname == "ling" and pwd == "123":
# print("Login successful!")
# func(*args,**kwargs)
# else:
# print("Login error!")
# return wrapper
# @check
# def name(usr):
# '''
# 函数执行时间是随机的。
# :return:
# '''
# time.sleep(random.randrange(3,6))
# print("%s,welcome to the page!" %(usr))
# name("ling")
# 四：编写装饰器，为多个函数加上认证的功能（用户的账号密码来源于文件），要求登录成功一次，后续的函数都无需再输入用户名和密码
# 注意：从文件中读出字符串形式的字典，可以用eval('{"name":"egon","password":"123"}')转成字典格式
# db='db.txt'
# login_status={'user':None,'status':False}
# def auth(auth_type='file'):
# def auth2(func):
# def wrapper(*args,**kwargs):
# if login_status['user'] and login_status['status']:
# return func(*args,**kwargs)
# if auth_type == 'file':
# with open(db,encoding='utf-8') as f:
# dic=eval(f.read())
# name=input('username: ').strip()
# password=input('password: ').strip()
# if name in dic and password == dic[name]:
# login_status['user']=name
# login_status['status']=True
# res=func(*args,**kwargs)
# return res
# else:
# print('username or password error')
# elif auth_type == 'sql':
# pass
# else:
# pass
# return wrapper
# return auth2
#
# @auth()
# def index():
# print('index')
#
# @auth(auth_type='file')
# def home(name):
# print('welcome %s to home' %name)
# index()
# home('egon')
# 五：编写装饰器，为多个函数加上认证功能，要求登录成功一次，在超时时间内无需重复登录，超过了超时时间，则必须重新登录
# import time,random
# user={'user':None,'login_time':None,'timeout':0.000003,}
#
# def timmer(func):
# def wrapper(*args,**kwargs):
# s1=time.time()
# res=func(*args,**kwargs)
# s2=time.time()
# print('%s' %(s2-s1))
# return res
# return wrapper
#
#
# def auth(func):
# def wrapper(*args,**kwargs):
# if user['user']:
# timeout=time.time()-user['login_time']
# if timeout < user['timeout']:
# return func(*args,**kwargs)
# name=input('name>>: ').strip()
# password=input('password>>: ').strip()
# if name == 'egon' and password == '123':
# user['user']=name
# user['login_time']=time.time()
# res=func(*args,**kwargs)
# return res
# return wrapper
#
# @auth
# def index():
# time.sleep(random.randrange(3))
# print('welcome to index')
#
# @auth
# def home(name):
# time.sleep(random.randrange(3))
# print('welcome %s to home ' %name)
#
# index()
# home('egon')
# 六：编写下载网页内容的函数，要求功能是：用户传入一个url，函数返回下载页面的结果
# from urllib.request import urlopen
#
# def get(url):
# return urlopen(url).read()
# print(get('https://www.baidu.com'))
# 七：为题目五编写装饰器，实现缓存网页内容的功能：
# 具体：实现下载的页面存放于文件中，如果文件内有值（文件大小不为0），就优先从文件中读取网页内容，否则，就去下载，然后存到文件中
# import requests
# import os
# cache_file='cache.txt'
# def make_cache(func):
# def wrapper(*args,**kwargs):
# if not os.path.exists(cache_file):
# with open(cache_file,'w'):pass
#
# if os.path.getsize(cache_file):
# with open(cache_file,'r',encoding='utf-8') as f:
# res=f.read()
# else:
# res=func(*args,**kwargs)
# with open(cache_file,'w',encoding='utf-8') as f:
# f.write(res)
# return res
# return wrapper
#
# @make_cache
# def get(url):
# return requests.get(url).text
# res=get('https://www.baidu.com')
# print(res)
# 扩展功能：用户可以选择缓存介质/缓存引擎，针对不同的url，缓存到不同的文件中
# import requests,os,hashlib
# engine_settings={
# 'file':{'dirname':'./db'},
# 'mysql':{
# 'host':'127.0.0.1',
# 'port':3306,
# 'user':'root',
# 'password':'123'},
# 'redis':{
# 'host':'127.0.0.1',
# 'port':6379,
# 'user':'root',
# 'password':'123'},
# }
#
# def make_cache(engine='file'):
# if engine not in engine_settings:
# raise TypeError('egine not valid')
# def deco(func):
# def wrapper(url):
# if engine == 'file':
# m=hashlib.md5(url.encode('utf-8'))
# cache_filename=m.hexdigest()
# cache_filepath=r'%s/%s' %(engine_settings['file']['dirname'],cache_filename)
#
# if os.path.exists(cache_filepath) and os.path.getsize(cache_filepath):
# return open(cache_filepath,encoding='utf-8').read()
#
# res=func(url)
# with open(cache_filepath,'w',encoding='utf-8') as f:
# f.write(res)
# return res
# elif engine == 'mysql':
# pass
# elif engine == 'redis':
# pass
# else:
# pass
#
# return wrapper
# return deco
#
# @make_cache(engine='file')
# def get(url):
# return requests.get(url).text
#
# # print(get('https://www.python.org'))
# print(get('https://www.baidu.com'))
# 八：还记得我们用函数对象的概念，制作一个函数字典的操作吗，来来来，我们有更高大上的做法，在文件开头声明一个空字典，然后在每个函数前加上装饰器，完成自动添加到字典的操作
# route_dic={}
#
# def make_route(name):
# def deco(func):
# route_dic[name]=func
# return deco
# @make_route('select')
# def func1():
# print('select')
#
# @make_route('insert')
# def func2():
# print('insert')
#
# @make_route('update')
# def func3():
# print('update')
#
# @make_route('delete')
# def func4():
# print('delete')
#
# print(route_dic)
# 九 编写日志装饰器，实现功能如：一旦函数f1执行，则将消息2017-07-21 11:12:11 f1 run写入到日志文件中，日志文件路径可以指定
# 注意：时间格式的获取
# import time
# time.strftime('%Y-%m-%d %X')
# import time
# import os
#
# def logger(logfile):
# def deco(func):
# if not os.path.exists(logfile):
# with open(logfile,'w'):pass
#
# def wrapper(*args,**kwargs):
# res=func(*args,**kwargs)
# with open(logfile,'a',encoding='utf-8') as f:
# f.write('%s %s run
' %(time.strftime('%Y-%m-%d %X'),func.__name__))
# return res
# return wrapper
# return deco
#
# @logger(logfile='aaaaaaaaaaaaaaaaaaaaa.log')
# def index():
# print('index')
#
# index()