Flask | Class Based Views

Sample class based views in flask

URL schema

url	method	description
/	GET	Get list of users
/	POST	Create new user
/<id>/	GET	Get an user by id
/<id>/	PUT	Update an user by id
/<id>/	DELETE	Delete an user by id

app.py

from flask import Flask, jsonify, request
from flask.views import MethodView

app = Flask(__name__)
app.url_map.strict_slashes = False


@app.errorhandler(Exception)
def handle_exception(e):
    return jsonify({'error': str(e)})


class UserAPI(MethodView):
    users = [
        {"pk": 1, "username": "Bret"},
        {"pk": 2, "username": "Antonette"},
        {"pk": 3, "username": "Samantha"},
        {"pk": 4, "username": "Karianne"},
        {"pk": 5, "username": "Kamren"},
    ]

    def get_user(self, pk):
        user = next(filter(lambda it: it['pk'] == pk, self.users), None)
        assert user is not None, "User not found"
        return user

    def get(self, pk=None):
        if pk is None:
            return jsonify(self.users)

        user = self.get_user(pk)
        return jsonify(user)

    def post(self):
        json = request.get_json()
        pk = json['pk']
        username = json['username']
        self.users.append({'pk': pk, 'username': username})
        return jsonify(self.users)

    def put(self, pk):
        json = request.get_json()
        username = json['username']
        user = self.get_user(pk)
        self.users.remove(user)
        self.users.append({'pk': pk, 'username': username})
        return jsonify(self.users)

    def delete(self, pk):
        user = self.get_user(pk)
        self.users.remove(user)
        return jsonify(self.users)


view = UserAPI.as_view('users')
app.add_url_rule(
    rule='/', 
    view_func=view, 
    methods=['GET', 'POST'],
)
app.add_url_rule(
    rule='/<int:pk>/', 
    view_func=view, 
    methods=['GET', 'PUT', 'DELETE'],
)

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

Usage

python app.py