flask-restful使用

安装

pip install flask-restful

基本使用

from flask import Flask
from flask_restful import Api, Resource

app = Flask(__name__)

# 1.创建api对象,用来管理资源(类视图)
api = Api(app)


# 2.定义类视图
class DemoView(Resource):

    def get(self):
        # 类视图返回的响应,默认返回application/json
        # 类视图可以直接返回字典,自动转换为json
        return {'message': 'get'}

    def post(self):
        return {'message': 'post'}


# 3.添加类视图, 类视图的函数标记默认为类名的小写,可以通过endpoint来修改
api.add_resource(DemoView, '/', endpoint='demo')

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

蓝图设置类视图

main.py文件

from flask import Flask
from user import user_blue

app = Flask(__name__)

# 4.注册蓝图
app.register_blueprint(user_blue)

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

user文件下__init__.py文件

from flask import Blueprint
from flask_restful import Api
from user.views import DemoView
# 1.创建蓝图对象
user_blue = Blueprint('user_b', __name__, url_prefix='/user')

# 2.创建api对象
user_api = Api(user_blue)

# 3.添加类视图
user_api.add_resource(DemoView, '/', endpoint='demo')

user文件下views.py文件

from flask_restful import Resource


class DemoView(Resource):

    def get(self):
        return {'message': 'get'}

    def post(self):
        return {'message': 'post'}

类视图设置装饰器

from flask import Flask
from flask_restful import Resource, Api

app = Flask(__name__)
api = Api(app)


def deco1(f):

    def wrapper(*args, **kwargs):
        print('装饰器1')
        return f(*args, **kwargs)

    return wrapper


def deco2(f):

    def wrapper(*args, **kwargs):
        print('装饰器2')
        return f(*args, **kwargs)

    return wrapper


class DemoResource(Resource):
    # method_decorators = [deco1, deco2] # 列表形式,所有的接口都使用这些装饰器
    method_decorators = {
        'get': [deco1],
        'post': [deco1, deco2]
    } # 字典形式,指定接口的装饰器

    def get(self):
        return {'message': 'get'}

    def post(self):
        return {'message': 'post'}


api.add_resource(DemoResource, '/', endpoint='demo')

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

请求解析

import re

from flask import Flask
from flask_restful import Resource, Api
from flask_restful.inputs import boolean, date, datetime_from_iso8601, int_range, regex
from flask_restful.reqparse import RequestParser

app = Flask(__name__)
api = Api(app)
'''
default:设置参数的默认值,如果没有传参会使用
required:是否必要,默认非必要,如果设置为True,没有传参会返回400
location:指定参数解析的位置 args/form/json/data/files/headers/cookies
type:指定参数转换的类型(格式转换&格式校验) int 内置类型 自定义
'''

# 自定义转换类型
def func1(value): # value就是解析出的参数
    # 格式校验
    if re.match(r'^user:', value):
        # 取出目标数据
        return value[5:]
    else:
        raise ValueError('Error:name paran error')


class DemoResource(Resource):

    def get(self):
        # 1.创建请求解析器
        parser = RequestParser()
        # 2.添加参数规则
        parser.add_argument('name')
        parser.add_argument('age')
        # 3.请求解析 默认会从查询字符串/post键值对/json字符串
        args = parser.parse_args()
        # 4.通过属性的方式取出参数
        print(args.name)
        print(args.age)
        return {'message': 'get'}

    def post(self):
        # 1.创建请求解析器
        parser = RequestParser()
        # 2.添加参数规则
        # parser.add_argument('name', required=True, location='args') # 设置必传,解析位置为查询字符串
        # parser.add_argument('age', default=10) # 未传参数时,设置默认值10
        parser.add_argument('age', type=int) # 转为整形
        # parser.add_argument('age', type=boolean) # 转为Bool类型 1/0 true/false
        # parser.add_argument('age', type=date) # 转为datetime类型 2019-10-01
        # parser.add_argument('age', type=datetime_from_iso8601) # 转为datetime类型 2012-01-01T23:30:00+02:00 日期+时间
        # parser.add_argument('age', type=int_range(10, 30)) # 转为整型,限定整数范围
        # parser.add_argument('age', type=regex(r'^1[3-9]\d{9}$')) # 正则格式校验

        parser.add_argument('name', type=func1) # 使用自定义的类型
        # 3.请求解析 默认会从查询字符串/post键值对/json字符串
        args = parser.parse_args()
        # 4.通过属性的方式取出参数
        print(args.name)
        print(args.age)
        return {'message': 'post'}


api.add_resource(DemoResource, '/', endpoint='demo')

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

序列化

from flask import Flask
from flask_restful import Resource, Api, fields, marshal, marshal_with

app = Flask(__name__)
api = Api(app)


class User:
    def __init__(self):
        self.name = 'zs'
        self.age = 20
        self.height = 1.98

    def to_dict(self):
        return {
            'username': self.name,
            'age': self.age,
            'height': self.height
        }


user_fields = {
    'username': fields.String(attribute='name'),
    'age': fields.Integer
}


class DemoResource(Resource):

    def get(self):
        user1 = User()  # 从数据库中查询出来
        return marshal(user1, user_fields)

    @marshal_with(user_fields)  # 装饰器用法
    def post(self):
        user2 = User()
        return user2

    def put(self):
        user3 = User()
        return user3.to_dict()


api.add_resource(DemoResource, '/', endpoint='demo')

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

自定义json

from flask import Flask
from flask_restful import Resource, Api, fields, marshal
from flask import make_response, current_app
from flask_restful.utils import PY3
from json import dumps

app = Flask(__name__)
api = Api(app)


class User:
    def __init__(self):
        self.name = 'zs'
        self.age = 20
        self.height = 1.98


user_fields = {
    'username': fields.String(attribute='name'),
    'age': fields.Integer
}


class DemoResource(Resource):

    def get(self):
        user1 = User()  # 从数据库中查询出来
        return marshal(user1, user_fields)


api.add_resource(DemoResource, '/', endpoint='demo')


@api.representation('application/json')  # 指定数据类型对应的转换函数
def output_json(data, code, headers=None):
    """Makes a Flask response with a JSON encoded body"""

    # 给字典设置外层包装
    if 'data' not in data:
        data = {
            'message': 'ok',
            'data': data
        }

    settings = current_app.config.get('RESTFUL_JSON', {})

    # If we're in debug mode, and the indent is not set, we set it to a
    # reasonable value here.  Note that this won't override any existing value
    # that was set.  We also set the "sort_keys" value.
    if current_app.debug:
        settings.setdefault('indent', 4)
        settings.setdefault('sort_keys', not PY3)

    # always end the json dumps with a new line
    # see https://github.com/mitsuhiko/flask/pull/1262
    dumped = dumps(data, **settings) + "\n"

    resp = make_response(dumped, code)
    resp.headers.extend(headers or {})
    return resp


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