身内のLTで使った資料です｡ サンプルコードは以下にあります｡ https://gist.github.com/kiakiraki/a1e352afeb79792d39e86bfd49d46654

1. Productive
RESTful API
development with
Flask-RESTPlus

2. • Sample code canbe found here:
https://gist.github.com/kiakiraki/a1e352afeb79792d39e86bfd49
d46654
• Sample project can be found here:
https://github.com/kiakiraki/flask-restplus-template

3. Introduction
• Web Frameworks for Python
The most popular
full-stack framework
The most popular
micro framework

4. Flask is Fun
A Minimal Application URL Parameters and Routing
from flask import Flask
app = Flask(__name__)
@app.route("/")
def hello():
return "Hello World!"
if __name__ == "__main__":
app.run()
@app.route('/user/<username>')
def show_user_profile(username):
return 'User %s' % username
@app.route('/post/<int:post_id>')
def show_post(post_id):
return 'Post %d' % post_id
@app.route('/path/<path:subpath>')
def show_subpath(subpath):
return 'Subpath %s' % subpath

5. Flask is not Fun
Handle HTTP Methods
• Handle HTTP method with
if statement
• Endpoints and Methods
correspond one-on-one
• Difficult to divide up,
the method is bloated
• Not bad, but a better way ...
@app.route('/login', methods=['GET',
'POST'])
def login():
if request.method == 'POST':
return do_the_login()
else:
return
show_the_login_form()

6. Easier ways to build RESTful API

7. What is
Flask-
RESTPlus?
• One of the Flask extensions
• A fork of Flask-RESTful
• Easy to build REST API

8. Good things of Flask-RESTPlus
• The endpoint corresponds to the Python Class
• HTTP method corresponds to Python method
• Validation of parameters
• Swagger document can be generated automatically

9. A Minimal Example
from flask import Flask
from flask_restplus import
(Api, Namespace, Resource)
app = Flask(__name__)
api = Api(
app,
title='Hello World!',
version='1.0',
description='てすとだよ')
hello_namespace = Namespace('helloworld',
description='end point of Hello World!’)
@hello_namespace.route('')
class HelloWorld(Resource):
def get(self):
return 'Hello World!', 200
def post(self):
return f'Hello {arguments}!', 200
if __name__ == '__main__':
api.add_namespace(hello_namespace)
app.run()

10. Automatic generation of
Swagger

11. Model definition and Validation
from flask import Flask, request
from flask_restplus import
(Api, Namespace, Resource, fields)
# 略
model_of_response = hello_namespace.model
('GET & POST method response’, {
'message': fields.String(
required=True,
description='response message',
example='Hello World!'
)
})
model_of_request = hello_namespace.model
('POST method request', {
'アイサツ': fields.String(
required=True,
description='古事記にも記されている通り実際奥ゆ
かしい作法',
example='ヘルカイト'
)
})

12. Model definition and Validation
@hello_namespace.route('')
class HelloWorld(Resource):
@hello_namespace.marshal_with(model_of_response)
def get(self):
response = {
'message': 'Hello World!'
}
return response, 200
@hello_namespace.marshal_with(model_of_response)
@hello_namespace.expect(model_of_request, varidate=True)
def post(self):
response = {
'message': f'ドーモ､{request.json["アイサツ"]} = サン'
}
return response, 200

15. END