Flask

Structure of Flask App

https://www.digitalocean.com/community/tutorials/how-to-structure-large-flask-applications

https://github.com/pallets/flask/wiki/Large-app-how-to

https://github.com/Robpol86/Flask-Large-Application-Example

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Make RESTful API with Flask

http://blog.luisrei.com/articles/flaskrest.html

• Create proper url (principle: everything is resource, Noun, not Verb)
• Define proper HTTP method
• Flask Request (handle client input)
  • Define header

from flask import json

@app.route('/messages', methods = ['POST'])
def api_message():

    if request.headers['Content-Type'] == 'text/plain':
        return "Text Message: " + request.data

    elif request.headers['Content-Type'] == 'application/json':
        return "JSON Message: " + json.dumps(request.json)

    elif request.headers['Content-Type'] == 'application/octet-stream':
        f = open('./binary', 'wb')
        f.write(request.data)
                f.close()
        return "Binary message written!"

    else:
        return "415 Unsupported Media Type ;)"

• Flask Response (use to return result)
  • Return response according to HTTP standard

from flask import Response

@app.route('/hello', methods = ['GET'])
def api_hello():
    data = {
        'hello'  : 'world',
        'number' : 3
    }
    js = json.dumps(data)

    resp = Response(js, status=200, mimetype='application/json')
    resp.headers['Link'] = 'http://luisrei.com'

    return resp

• Error handling
• Authorization

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Flask-Restful

Request Parsing

Flask-RESTful’s request parsing interface, reqparse, is modeled after the argparse interface. It’s designed to provide simple and uniform access to any variable on the flask.request object in Flask.