python实现Restful服务 (基于flask)(1)

参考：https://www.jianshu.com/p/6ac1cab17929

参考：https://www.cnblogs.com/alexyuyu/p/6243362.html

参考：http://docs.jinkan.org/docs/flask/quickstart.html.

安装基于REST的Web客户端

1、helloworld的运行

from flask import Flask

# Flask初始化参数尽量使用你的包名，这个初始化方式是官方推荐的，官方解释：http://flask.pocoo.org/docs/0.12/api/#flask.Flask

app = Flask(__name__)

@app.route('/HelloWorld')

def hello_world():

    return "Hello World!"

app.run()

2、使用get 方法获取资源

# -*- coding: utf-8 -*-

from flask import Flask, jsonify, abort, make_response

app = Flask(__name__)

articles = [

    {

        'id': 1,

        'title': 'the way to python',

        'content': 'tuple, list, dict'

    },

    {

        'id': 2,

        'title': 'the way to REST',

        'content': 'GET, POST, PUT'

    }

]

@app.route('/blog/api/articles', methods=['GET'])

def get_articles():

    return jsonify({'articles': articles})

@app.route('/blog/api/articles/<int:article_id>', methods=['GET'])

def get_article(article_id):

    article = filter(lambda a: a['id'] == article_id, articles)

    if len(article) == 0:

        abort(404)

    return jsonify({'article': article[0]})

@app.errorhandler(404)

def not_found(error):

    return make_response(jsonify({'error': 'Not found'}), 404)

if __name__ == '__main__':

    app.run(host='127.0.0.1', port=5632)

在终端输入如下得到结果：

$ curl -i http://localhost:5632/blog/api/articles

HTTP/1.0 200 OK

Content-Type: application/json

Content-Length: 225

Server: Werkzeug/0.12.2 Python/3.6.3

Date: Thu, 22 Mar 2018 15:36:17 GMT

{

  "articles": [

    {

      "content": "tuple, list, dict",

      "id": 1,

      "title": "the way to python"

    },

    {

      "content": "GET, POST, PUT",

      "id": 2,

      "title": "the way to REST"

    }

  ]

}

3、使用flask的RESTful扩展库

from flask import Flask

from flask_restful import reqparse, abort, Api, Resource

app = Flask(__name__)

api = Api(app)

TODOS = {

    'todo1': {'task': 'build an API'},

    'todo2': {'task': '哈哈哈'},

    'todo3': {'task': 'profit!'},

}

def abort_if_todo_doesnt_exist(todo_id):

    if todo_id not in TODOS:

        abort(404, message="Todo {} doesn't exist".format(todo_id))

parser = reqparse.RequestParser()

parser.add_argument('task')

# Todo

# shows a single todo item and lets you delete a todo item

class Todo(Resource):

    def get(self, todo_id):

        abort_if_todo_doesnt_exist(todo_id)

        return TODOS[todo_id]

    def delete(self, todo_id):

        abort_if_todo_doesnt_exist(todo_id)

        del TODOS[todo_id]

        return '', 204

    def put(self, todo_id):

        args = parser.parse_args()

        task = {'task': args['task']}

        TODOS[todo_id] = task

        return task, 201

# TodoList

# shows a list of all todos, and lets you POST to add new tasks

class TodoList(Resource):

    def get(self):

        return TODOS

    def post(self):

        args = parser.parse_args()

        todo_id = int(max(TODOS.keys()).lstrip('todo')) + 1

        todo_id = 'todo%i' % todo_id

        TODOS[todo_id] = {'task': args['task']}

        return TODOS[todo_id], 201

##

## Actually setup the Api resource routing here

##

api.add_resource(TodoList, '/todos')

api.add_resource(Todo, '/todos/<todo_id>')

if __name__ == '__main__':

    app.run()

查询列表结果：

查询单任务：

删除任务：

另一个例子：

from flask import Flask

from flask_restful import reqparse, abort, Api, Resource

app = Flask(__name__)

api = Api(app)

TODOS = {

    'todo1': {'task': 'build an API'},

    'todo2': {'task': '?????'},

    'todo3': {'task': 'profit!'},

}

def abort_if_todo_doesnt_exist(todo_id):

    if todo_id not in TODOS:

        abort(404, message="Todo {} doesn't exist".format(todo_id))

parser = reqparse.RequestParser()

parser.add_argument('task')

# Todo

# shows a single todo item and lets you delete a todo item

class Todo(Resource):

    def get(self, todo_id):

        abort_if_todo_doesnt_exist(todo_id)

        return TODOS[todo_id]

    def delete(self, todo_id):

        abort_if_todo_doesnt_exist(todo_id)

        del TODOS[todo_id]

        return '', 204

    def put(self, todo_id):

        args = parser.parse_args()

        task = {'task': args['task']}

        TODOS[todo_id] = task

        return task, 201

# TodoList

# shows a list of all todos, and lets you POST to add new tasks

class TodoList(Resource):

    def get(self):

        return TODOS

    def post(self):

        args = parser.parse_args()

        todo_id = int(max(TODOS.keys()).lstrip('todo')) + 1

        todo_id = 'todo%i' % todo_id

        TODOS[todo_id] = {'task': args['task']}

        return TODOS[todo_id], 201

##

## Actually setup the Api resource routing here

##

api.add_resource(TodoList, '/todos')

api.add_resource(Todo, '/todos/<todo_id>')

if __name__ == '__main__':

    app.run(debug=True)

通过终端进行如下相应任务：

获取列表：

$ curl http://localhost:5000/todos

{"todo1": {"task": "build an API"}, "todo2": {"task": "?????"}, "todo3": {"task": "profit!"}}

获取单个任务：

$ curl http://localhost:5000/todos/todo3

{"task": "profit!"}

删除一个任务：

curl http://localhost:5000/todos/todo2 -X DELETE -v

增加一个任务：

$ curl http://localhost:5000/todos -d "task=something new" -X POST -v

更新一个任务：

$ curl http://localhost:5000/todos/todo3 -d "task=something different" -X PUT -v