flask-restful 快速入门

Flask-RESTful 是一个 Flask 扩展，它添加了快速构建 REST APIs 的支持。它当然也是一个能够跟你现有的ORM/库协同工作的轻量级的扩展。

快速入门

api.py

from flask import Flask
from flask.ext import restful

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

class HelloWorld(restful.Resource):
    def get(self):
        return {'hello': 'world'}

api.add_resource(HelloWorld, '/')

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

运行

$ python api.py
 * Running on http://127.0.0.1:5000/

另打开一个命令窗口，测试这个API：

$ curl http://127.0.0.1:5000/
{"hello": "world"}

心得

  • api.add_resource(HelloWorld, '/')，add_resource函数添加类HelloWorld
  • curl时，返回{'hello': 'world'}，默认是GET
  • -X后面的命令不分大小写

证例如下

jihite@ubuntu:~$ curl http://127.0.0.1:5000
{
    "hello": "world"
}
jihite@ubuntu:~$ curl http://127.0.0.1:5000 -X GET
{
    "hello": "world"
}
jihite@ubuntu:~$ curl http://127.0.0.1:5000 -X get
{
    "hello": "world"
}
jihite@ubuntu:~$ curl http://127.0.0.1:5000 -X Get
{
    "hello": "world"
}

资源丰富的路由

Flask-RESTful 提供的最主要的基础就是资源(resources)

api_Routing.py

from flask import Flask, request
from flask.ext.restful import Resource, Api

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

todos = {}

class TodoSimple(Resource):
    def get(self, todo_id):
        return {todo_id: todos[todo_id]}

    def put(self, todo_id):
        todos[todo_id] = request.form['data']
        return {todo_id: todos[todo_id]}

api.add_resource(TodoSimple, '/<string:todo_id>')

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

运行

$ python api_Routing.py
 * Running on http://127.0.0.1:5000/

另一命令窗口

jihite@ubuntu:~$ curl http://127.0.0.1:5000/todo1 -d 'data=apple' -X PUT
{
    "todo1": "apple"
}
jihite@ubuntu:~$ curl http://127.0.0.1:5000/todo1
{
    "todo1": "apple"
}
jihite@ubuntu:~$ curl http://127.0.0.1:5000/todo2 -d 'data=banana' -X PUT
{
    "todo2": "banana"
}
jihite@ubuntu:~$ curl http://127.0.0.1:5000/todo2 
{
    "todo2": "banana"
}

心得

  • -d 是增加数据的参数
  • 因put函数中request.form['data']找'data'这一项，所有-d 后面的数据必须有 data=

证例如下

jihite@ubuntu:~$ curl http://127.0.0.1:5000/todo1 -d 'data=jimi' -X PUT
{
    "todo1": "jimi"
}
jihite@ubuntu:~$ curl http://127.0.0.1:5000/todo1  -X GET
{
    "todo1": "jimi"
}
jihite@ubuntu:~$ curl http://127.0.0.1:5000/todo1 -d 'task=jimi' -X PUT
{
    "message": "The browser (or proxy) sent a request that this server could not understand."   #server无法理解请求
}

多种类型的返回值

api_mulout.py

from flask import Flask, request
from flask.ext.restful import Resource, Api

app = Flask(__name__)
api = Api(app)
todos = {}

class Todo1(Resource):
    def get(self):
        return {'task': 'apple'}

class Todo2(Resource):
    def get(self):
        return {'task': 'babana'}, 201

class Todo3(Resource):
    def get(self):
        return {'task': 'pear'}, 201, {'data': 'peach'}

api.add_resource(Todo1, '/Todo1')
api.add_resource(Todo2, '/Todo2')
api.add_resource(Todo3, '/Todo3')


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

运行

$ python api_mulout.py 
 * Running on http://127.0.0.1:5000/ (Press CTRL+C to quit)
 * Restarting with stat

另一命令行窗口

jihite@ubuntu:~/project/flask$ curl http://127.0.0.1:5000/Todo1
{
    "task": "apple"
}
jihite@ubuntu:~/project/flask$ curl http://127.0.0.1:5000/Todo2
{
    "task": "babana"
}
jihite@ubuntu:~/project/flask$ curl http://127.0.0.1:5000/Todo3
{
    "task": "pear"
}
jihite@ubuntu:~/project/flask$ curl http://127.0.0.1:5000/Todo4
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN">
<title>404 Not Found</title>
<h1>Not Found</h1>
<p>The requested URL was not found on the server.  If you entered the URL manually please check your spelling and try again.</p>

心得

  • api.add_resource通过第二个参数关联第一个参数指定的类

多URL访问同一个资源

api_points.py

from flask import Flask
from flask.ext import restful

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

class HelloWorld(restful.Resource):
    def get(self):
        return {'hello': 'world'}

api.add_resource(HelloWorld, '/', '/hello')

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

运行

$ python api_points.py 
 * Running on http://127.0.0.1:5000/ (Press CTRL+C to quit)
 * Restarting with stat

另一个命令窗口执行

jihite@ubuntu:~/project/flask$ curl http://127.0.0.1:5000/
{
    "hello": "world"
}
jihite@ubuntu:~/project/flask$ curl http://127.0.0.1:5000/hello
{
    "hello": "world"
}

完整案例

whole.py

from flask import Flask
from flask.ext.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', type=str)


# Todo
#   show a single todo item and lets you delete them
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)

运行

$ python whole.py
 * Running on http://127.0.0.1:5000/ (Press CTRL+C to quit)
 * Restarting with stat

另一个命令窗口执行

jihite@ubuntu:~/project/flask$ curl http://127.0.0.1:5000/todos
{
    "todo1": {
        "task": "build an API"
    }, 
    "todo2": {
        "task": "?????"
    }, 
    "todo3": {
        "task": "profit!"
    }
}
jihite@ubuntu:~/project/flask$ curl http://127.0.0.1:5000/todos/todo2
{
    "task": "?????"
}
jihite@ubuntu:~/project/flask$ curl http://127.0.0.1:5000/todos -d 'task=hello' -X POST -v
* Hostname was NOT found in DNS cache
*   Trying 127.0.0.1...
* Connected to 127.0.0.1 (127.0.0.1) port 5000 (#0)
> POST /todos HTTP/1.1
> User-Agent: curl/7.37.1
> Host: 127.0.0.1:5000
> Accept: */*
> Content-Length: 10
> Content-Type: application/x-www-form-urlencoded
> 
* upload completely sent off: 10 out of 10 bytes
* HTTP 1.0, assume close after body
< HTTP/1.0 201 CREATED
< Content-Type: application/json
< Content-Length: 24
< Server: Werkzeug/0.10.4 Python/2.7.8
< Date: Tue, 14 Jul 2015 06:29:19 GMT
< 
{
    "task": "hello"
}
* Closing connection 0
jihite@ubuntu:~/project/flask$ curl http://127.0.0.1:5000/todos
{
    "todo1": {
        "task": "build an API"
    }, 
    "todo2": {
        "task": "?????"
    }, 
    "todo3": {
        "task": "profit!"
    }, 
    "todo4": {
        "task": "hello"
    }
}
jihite@ubuntu:~/project/flask$ curl http://127.0.0.1:5000/todos/todo2 -X DELETE -v
* Hostname was NOT found in DNS cache
*   Trying 127.0.0.1...
* Connected to 127.0.0.1 (127.0.0.1) port 5000 (#0)
> DELETE /todos/todo2 HTTP/1.1
> User-Agent: curl/7.37.1
> Host: 127.0.0.1:5000
> Accept: */*
> 
* HTTP 1.0, assume close after body
< HTTP/1.0 204 NO CONTENT
< Content-Type: application/json
< Content-Length: 0
< Server: Werkzeug/0.10.4 Python/2.7.8
< Date: Tue, 14 Jul 2015 06:29:37 GMT
< 
* Closing connection 0
jihite@ubuntu:~/project/flask$ curl http://127.0.0.1:5000/todos
{
    "todo1": {
        "task": "build an API"
    }, 
    "todo3": {
        "task": "profit!"
    }, 
    "todo4": {
        "task": "hello"
    }
}
jihite@ubuntu:~/project/flask$ curl http://127.0.0.1:5000/todos/todo3 -d 'task=misi' -X PUT -v
* Hostname was NOT found in DNS cache
*   Trying 127.0.0.1...
* Connected to 127.0.0.1 (127.0.0.1) port 5000 (#0)
> PUT /todos/todo3 HTTP/1.1
> User-Agent: curl/7.37.1
> Host: 127.0.0.1:5000
> Accept: */*
> Content-Length: 9
> Content-Type: application/x-www-form-urlencoded
> 
* upload completely sent off: 9 out of 9 bytes
* HTTP 1.0, assume close after body
< HTTP/1.0 201 CREATED
< Content-Type: application/json
< Content-Length: 23
< Server: Werkzeug/0.10.4 Python/2.7.8
< Date: Tue, 14 Jul 2015 06:30:24 GMT
< 
{
    "task": "misi"
}
* Closing connection 0
jihite@ubuntu:~/project/flask$ curl http://127.0.0.1:5000/4
{
    "todo1": {
        "task": "build an API"
    }, 
    "todo3": {
        "task": "misi"
    }, 
    "todo4": {
        "task": "hello"
    }
}
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原文地址：https://www.cnblogs.com/kaituorensheng/p/4645080.html