flask框架中间件

Flask框架中间件是指在请求到达视图函数之前或之后，对请求或响应进行处理的函数。在Flask中，中间件可以通过装饰器或者Flask提供的钩子函数来实现。下面是两种实现方式的例子：

1.使用装饰器实现中间件

from flask import Flask, request

app = Flask(__name__)

@app.before_request
def before_request():
    print('This is a middleware before request.')
    
@app.after_request
def after_request(response):
    print('This is a middleware after request.')
    return response

@app.route('/')
def index():
    return 'Hello World!'

if __name__ == '__main__':
    app.run()

2.使用钩子函数实现中间件

from flask import Flask, request

app = Flask(__name__)

def before_request():
    print('This is a middleware before request.')
    
def after_request(response):
    print('This is a middleware after request.')
    return response

app.before_request(before_request)
app.after_request(after_request)

@app.route('/')
def index():
    return 'Hello World!'

if __name__ == '__main__':
    app.run()