補充

pipreqs：

- 項目依賴 pip3 install pipreqs
- 生成依賴文件：pipreqs ./ 
- 安裝依賴文件：pip3 install -r requirements.txt 

 

函數和方法

from types import MethodType,FunctionType
​
class Foo(object):
    def fetch(self):
        pass
​
print(isinstance(Foo.fetch,MethodType))
print(isinstance(Foo.fetch,FunctionType)) # True
​
obj = Foo()
print(isinstance(obj.fetch,MethodType)) # True
print(isinstance(obj.fetch,FunctionType))

threading.local

多個線程修改同一個數據，複製多份變量給每個線程用,爲每個線程開闢一塊空間進行數據存儲

不用threading.local

# 不用local
from threading import Thread
import time
lqz = -1
def task(arg):
    global lqz
    lqz = arg
    # time.sleep(2)
    print(lqz)
​
for i in range(10):
    t = Thread(target=task,args=(i,))
    t.start()

threading.local使用

from threading import Thread
from threading import local
import time
from threading import get_ident
# 特殊的對象
lqz = local()
def task(arg):
    # 對象.val = 1/2/3/4/5
    lqz.value = arg
    time.sleep(2)
    print(lqz.value)
for i in range(10):
    t = Thread(target=task,args=(i,))
    t.start()

通過字典自定義threading.local（函數）

from threading import get_ident,Thread
import time
storage = {}
def set(k,v):
    ident = get_ident()
    if ident in storage:
        storage[ident][k] = v
    else:
        storage[ident] = {k:v}
def get(k):
    ident = get_ident()
    return storage[ident][k]
def task(arg):
    set('val',arg)
    v = get('val')
    print(v)
​
for i in range(10):
    t = Thread(target=task,args=(i,))
    t.start()

面向對象版

from threading import get_ident,Thread
import time
class Local(object):
    storage = {}
    def set(self, k, v):
        ident = get_ident()
        if ident in Local.storage:
            Local.storage[ident][k] = v
        else:
            Local.storage[ident] = {k: v}
    def get(self, k):
        ident = get_ident()
        return Local.storage[ident][k]
obj = Local()
def task(arg):
    obj.set('val',arg) 
    v = obj.get('val')
    print(v)
for i in range(10):
    t = Thread(target=task,args=(i,))
    t.start()

通過setattr和getattr實現

from threading import get_ident,Thread
import time
class Local(object):
    storage = {}
    def __setattr__(self, k, v):
        ident = get_ident()
        if ident in Local.storage:
            Local.storage[ident][k] = v
        else:
            Local.storage[ident] = {k: v}
    def __getattr__(self, k):
        ident = get_ident()
        return Local.storage[ident][k]
obj = Local()
def task(arg):
    obj.val = arg
    print(obj.val)
for i in range(10):
    t = Thread(target=task,args=(i,))
    t.start()

每個對象有自己的存儲空間（字典）

from threading import get_ident,Thread
import time
class Local(object):
    def __init__(self):
        object.__setattr__(self,'storage',{})
    def __setattr__(self, k, v):
        ident = get_ident()
        if ident in self.storage:
            self.storage[ident][k] = v
        else:
            self.storage[ident] = {k: v}
    def __getattr__(self, k):
        ident = get_ident()
        return self.storage[ident][k]
obj = Local()
def task(arg):
    obj.val = arg
    obj.xxx = arg
    print(obj.val)
for i in range(10):
    t = Thread(target=task,args=(i,))
    t.start()

兼容線程和協程

try:
    from greenlet import getcurrent as get_ident
except Exception as e:
    from threading import get_ident
from threading import Thread
import time
class Local(object):
    def __init__(self):
        object.__setattr__(self,'storage',{})
    def __setattr__(self, k, v):
        ident = get_ident()
        if ident in self.storage:
            self.storage[ident][k] = v
        else:
            self.storage[ident] = {k: v}
    def __getattr__(self, k):
        ident = get_ident()
        return self.storage[ident][k]
obj = Local()
def task(arg):
    obj.val = arg
    obj.xxx = arg
    print(obj.val)
for i in range(10):
    t = Thread(target=task,args=(i,))
    t.start()

partial偏函數

#偏函數的第二個部分(可變參數)，按原有函數的參數順序進行補充，參數將作用在原函數上，最後偏函數返回一個新函數
from functools import partial
def test(a,b,c,d):
    return a+b+c+d
​
tes=partial(test,1,2)
print(tes(3,4))

session源碼分析

SecureCookieSessionInterface
    -open_session
    -save_session