def func():# 函數(shù)名僅僅只是個(gè)綁定內(nèi)存地址的變量 
	print("i`m running") 
# 這是調(diào)用  
func()  # i`m running
# 這是對(duì)象引用，引用的是內(nèi)存地址  
func2 = func  
print(func2 is func)  # True
# 通過引用進(jìn)行調(diào)用  
func2()  # i`m running

def decorator_get_function_name(func):
	"""
	獲取正在運(yùn)行函數(shù)名
	:return:
	"""
	def wrapper(*arg):
		"""
		wrapper
		:param arg:
		:return:
		"""
		print(f"當(dāng)前運(yùn)行方法名：{func.__name__}  with  params: {arg}")
		return func(*arg)
	return wrapper
@decorator_get_function_name
def test_func_add(x, y):
	print(x + y)
@decorator_get_function_name
def test_func_sub(x, y):
	print(x - y)
test_func_add(1, 2)
# 當(dāng)前運(yùn)行方法名：test_func_add  with  params: (1, 2)
# 3
test_func_sub(3, 5)
# 當(dāng)前運(yùn)行方法名：test_func_sub  with  params: (3, 5)
# -2

def login_check(func):
 def wrapper(request, *args, **kwargs):
  if not request.session.get('login_status'):
return HttpResponseRedirect('/api/login/')
  return func(request, *args, **kwargs)
 return wrapper
@login_check
def edit_config():
	pass

"""
>  1. def login_check(func):  ==>將login_check函數(shù)加載到內(nèi)存
>  ....
>  @login_check  ==>此處已經(jīng)在內(nèi)存中將login_check這個(gè)函數(shù)執(zhí)行了??；并不需要等edit_config()實(shí)例化調(diào)用
>  2. 上例@login_check內(nèi)部會(huì)執(zhí)行以下操作：
>	  2.1 執(zhí)行l(wèi)ogin_check函數(shù)，并將 @login_check 下面的 函數(shù)(edit_config) 作為login_check函數(shù)的參數(shù)，即：@login_check 等價(jià)于 login_check(edit_config)
>  2.2 內(nèi)部就會(huì)去執(zhí)行：
def wrapper(*args):
 # 校驗(yàn)session...
 return func(request, *args, **kwargs)# func是參數(shù)，此時(shí) func 等于 edit_config，此處相當(dāng)于edit_config(request, *args, **kwargs)
return wrapper  # 返回的 wrapper，wrapper代表的是函數(shù)對(duì)象，非函數(shù)實(shí)例化對(duì)象
2.3 其實(shí)就是將原來的 edit_config 函數(shù)塞進(jìn)另外一個(gè)函數(shù)中,另一個(gè)函數(shù)當(dāng)中可以做一些操作；再執(zhí)行edit_config
2.4 將執(zhí)行完的 login_check 函數(shù)返回值(也就是 wrapper對(duì)象)將此返回值再重新賦值給新 edit_config，即：
2.5 新edit_config = def wrapper:
 # 校驗(yàn)session...
return 原來edit_config(request, *args, **kwargs) 
>  3. 也就是新edit_config()=login_check(edit_config):wrapper(request, *args, **kwargs):return edit_config(request, *args, **kwargs) 有點(diǎn)繞，大家看步驟細(xì)細(xì)理解。
"""

from functools import wraps
def w1(func):
	@wraps(func)
	def wrapper(*args, **kwargs):
		print("這里是第一個(gè)校驗(yàn)")
		return func(*args, **kwargs)
	return wrapper
def w2(func):
	@wraps(func)
	def wrapper(*args, **kwargs):
		print("這里是第二個(gè)校驗(yàn)")
		return func(*args, **kwargs)
	return wrapper
def w3(func):
	def wrapper(*args, **kwargs):
		print("這里是第三個(gè)校驗(yàn)")
		return func(*args, **kwargs)
	return wrapper
@w2  # 這里其實(shí)是w2(w1(f1))
@w1  # 這里是w1(f1)
def f1():
	print(f"i`m f1, at {f1}")
@w3
def f2():
	print(f"i`m f2, at {f2}")
# ====================== 實(shí)例化階段 =====================
f1()
# 這里是第二個(gè)校驗(yàn)
# 這里是第一個(gè)校驗(yàn)
# i`m f1, at <function f1 at 0x7febc52f5e50>
f2()
# 這里是第三個(gè)校驗(yàn)
# i`m f2, at <function w3.<lo

def decorator_get_function_duration(enable):
	"""
	:param enable:  是否需要統(tǒng)計(jì)函數(shù)執(zhí)行耗時(shí)
	:return: 
	"""
	print("this is decorator_get_function_duration")
	def inner(func):
		print('this is inner in decorator_get_function_duration')
		@wraps(func)
		def wrapper(*args, **kwargs):
			print('this is a wrapper in decorator_get_function_duration.inner')
			if enable:
				start = time.time()
				print(f"函數(shù)執(zhí)行前：{start}")
				result = func(*args, **kwargs)
				print('[%s]`s enable was %s it`s duration : %.3f s ' % (func.__name__, enable, time.time() - start))
			else:
				result = func(*args, **kwargs)
			return result
		return wrapper
	return inner
def decorator_1(func):
	print('this is decorator_1')
	@wraps(func)
	def wrapper(*args, **kwargs):
		print('this is a wrapper in decorator_1')
		return func(*args, **kwargs)
	return wrapper
def decorator_2(func):
	print('this is decorator_2')
	@wraps(func)
	def wrapper(*args, **kwargs):
		print('this is a wrapper in decorator_2')
		return func(*args, **kwargs)
	return wrapper
@decorator_1 # 此處相當(dāng):decorator_1(decorator_2(decorator_get_function_duration(enable=True)(fun)))
@decorator_2 # = decorator_2(decorator_get_function_duration(enable=True)(fun))
@decorator_get_function_duration(enable=True)  # = decorator_get_function_duration(enable=True)(fun)
def fun():
	time.sleep(2)
	print("fun 執(zhí)行完了～")
fun()
# ======== enable=False ============
"""
this is decorator_get_function_duration
this is inner in decorator_get_function_duration
this is decorator_2
this is decorator_1
this is a wrapper in decorator_1
this is a wrapper in decorator_2
this is a wrapper in decorator_get_function_duration.inner
fun 執(zhí)行完了～
"""
# ======== enable=True ============
"""
this is decorator_get_function_duration
this is inner in decorator_get_function_duration
this is decorator_2
this is decorator_1
this is a wrapper in decorator_1
this is a wrapper in decorator_2
this is a wrapper in decorator_get_function_duration.inner
函數(shù)執(zhí)行前：1634635708.648994
fun 執(zhí)行完了～
[fun]`s enable was True it`s duration : 2.002 s 
"""