【flask】flask-restful、简单使用、类视图装饰器、蓝图与类视图

逃离我推掉我的手 2022-11-21 11:50 171阅读 0赞

#### 1.flask-restful ####

Flask-RESTful 是一个 Flask 扩展，它添加了快速构建 REST APIs 的支持

安装

pip install flask-restful

文档

官方文档 https://flask-restful.readthedocs.io/en/latest
    中文翻译 http://www.pythondoc.com/Flask-RESTful/index.html

#### 2.简单使用 ####

1）组件对象 = Api(app)  
2）自定义视图类(Resource)  
3）组件对象.add\_resource(视图类, URL资源段)

from flask import Flask
    from flask_restful import Api, Resource
    
    app = Flask(__name__)
    api = Api(app)  # 创建Api对象
    
    # 自定义视图类
    class DemoResource(Resource):
    
        def get(self):
            return { "code": 0, "msg": "get方法"}
    
        def post(self):
            return { "code": 0, "msg": "post方法"}
    
    
    api.add_resource(DemoResource, "/")  # 添加资源，绑定是视图类与路径
    
    if __name__ == '__main__':
        app.run(debug=True)

使用视图类的好处：  
1）响应头的content-type为json  
2）返回值的字典会自动转为json字符串

#### 3.类视图装饰器 ####

如果我们需要在类视图中使用装饰器，我们可以在`method_decorators`属性指定装饰器，让它是列表时装饰全部函数，是字典时可以单独控制函数

from flask import Flask
    from flask_restful import Api, Resource
    
    app = Flask(__name__)
    api = Api(app)
    
    def my_decorator1(func):
        print("my_decorator1")
        def wrapper(*args, **kwargs):
            print("my_decorator1 dispatch")
            return func(*args, **kwargs)
        return wrapper
    
    
    def my_decorator2(func):
        print("my_decorator2")
        def wrapper(*args, **kwargs):
            print("my_decorator2 dispatch")
            return func(*args, **kwargs)
        return wrapper
    
    
    class DemoResource(Resource):
        # 给所有视图函数都添加装饰器
        # method_decorators = [my_decorator1, my_decorator2]
    
        # 给指定函数添加指定的装饰器
        method_decorators = { 
            "get": [my_decorator1, my_decorator2],  # get方法被装饰器1和装饰器2装饰
            "post": [my_decorator1]  # post方法只被装饰器1装饰
        }
    
        def get(self):
            return { "get": "get message"}
    
        def post(self):
            return { "post": "post message"}
    
    
    api.add_resource(DemoResource, "/")
    
    if __name__ == '__main__':
        app.run(debug=True)

#### 4.蓝图与类视图 ####

flask-restful的蓝图与flask的蓝图差不多

\_\_init\_\_.py

from flask import Blueprint
    from flask_restful import Api
    from user.views import DemoResource
    
    # 1.创建蓝图对象
    user_blu = Blueprint('user', __name__, url_prefix='/user')
    
    # 2.创建蓝图对应的api对象
    user_api = Api(user_blu)
    
    # 3.添加类视图
    user_api.add_resource(DemoResource, '/')
    
    # flask写法
    # from flask import Blueprint
    # user_bp = Blueprint("user", __name__, url_prefix="/user")
    # from .views import *

views.py

from flask_restful import Resource
    
    class DemoResource(Resource):
        def get(self):
            return { 'method': 'get_method'}
    
        def post(self):
            return { 'method': 'post_method'}
            
    # flask写法
    # @user_bp.route("/info")
    # def user_info():
    # return "个人信息"

main.py

from flask import Flask
    from user import user_blu
    
    app = Flask(__name__)
    
    app.register_blueprint(user_blu)
    
    # flask写法（没区别）
    # app.register_blueprint(user_bp)
    
    if __name__ == '__main__':
        print(app.url_map)
        app.run(debug=True)