中间件

中间件

from flask import Flask
app = Flask(__name__)
app.secret_key = 'asdfasdfasdf'

@app.route('/x2',methods=['GET','POST'])
def index():
    return "x2"


class Middleware(object):
    def __init__(self,old_wsgi_app):
        """
        服务端启动时，自动执行
        :param old_wsgi_app:
        """
        self.old_wsgi_app =old_wsgi_app

    def __call__(self, environ, start_response):
        """
        每次有用户请求道来时
        :param args:
        :param kwargs:
        :return:
        """
        print('before')
        from flask import session,request
        obj = self.old_wsgi_app(environ, start_response)
        print('after')
        return obj

if __name__ == '__main__':
    app.wsgi_app = Middleware(app.wsgi_app)
    app.run()
    """
    1.执行app.__call__
    2.在调用app.wsgi_app方法
    """

方法和函数

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))