Aplicação Web Restful simples utilizando o microframework Flask e a extenção Flask-Classy

gistfile1.py

from flask import Flask, g, request, jsonify, abort # http://flask.pocoo.org/
from flask.ext.classy import FlaskView # http://pythonhosted.org/Flask-Classy/
from db import DatabaseConnection, BaseManager, BaseEntity # https://gist.github.com/fernandojunior/63c6c676f6e16a1a7f0e

"""
Aplicação Web Restful simples utilizando o microframework Flask e a extenção Flask-Classy

Author Fernando Felix do Nascimento Junior
Gist https://gist.github.com/fernandojunior/45efd7f525338a82475c
"""

class Entry(BaseEntity):

    def __init__(self, title, text, id=None):
        self.id = id
        self.title = title
        self.text = text

    @classmethod
    def schema(cls):
        return """
            drop table if exists entry;

            create table entry (
                id integer primary key autoincrement,
                title text not null,
                text text not null
            );
        """

class EntriesView(FlaskView):
    """
	
	Classe que define views para gerenciar Entries.

	Metodo HTTP - Metodo View - Acao - Exemplo
	GET - index - Obtem informacoes sobre os recursos - http://<servername>/api/1.0/entries
	GET - get - Obtem informacoes sobre um recurso - http://<servername>/api/1.0/entries/3
	POST - post - Cria um novo recurso - http://<servername>/api/1.0/entries (cria uma nova entry, a partir dos dados fornecidos com a requisicao)
	PUT - put - Atualiza um recurso - http://<servername>/api/1.0/entries/123 (atualiza a entry #123, a partir dos dados fornecidos com a requisicao)
	DELETE - delete - Deleta um recurso - http://<servername>/api/1.0/entries/123 (deleta entry #123)
	
	Exemplo de requisicao AJAX:
	
        $.ajax(
            {
                url: '<servername>/api/1.0/entries/1',
                type: "PUT",
                contentType: "application/json; charset=utf-8",
                data: JSON.stringify({
                    title: "novo titulo da entry",
                    //text: "algum texto"
                }),
                dataType: "json",
                success: function (data) {
                    alert("atualizando uma entry. Response: " + data.result);
                }
            }
        )
	
    """

    route_prefix = '/api/1.0/'
	
    @property
    def __objects(self):
        return g.objects(Entry)

    def index(self):

        data = self.__objects.all()
        result = [d.__dict__ for d in data]
        return jsonify(entries=result)

    def get(self, id):
        if not self.__objects.has(id):
            abort(404)

        result = self.__objects.get(id).__dict__
        return jsonify(entry=result)
	
    def post(self):
	
        if not request.json:
            abort(400)

        if not 'title' in request.json:
            abort(400)

        if not 'text' in request.json:
            abort(400)

        e = Entry(request.json['title'], request.json['text'])
        id = self.__objects.save(e)

        self.__objects.commit()

        return jsonify(result=id)

    def put(self, id):
        
        if not self.__objects.has(id):
            abort(404)

        e = self.__objects.get(id)

        if 'title' in request.json:
            e.title = request.json['title']
			
        if 'text' in request.json:
            e.text = request.json['text']
			
        #for key, value in request.json:
        #    setattr(e, key, value)

        self.__objects.update(e)
        self.__objects.commit()

        return jsonify(result='True'), 200
		
    def delete(self, id):
        
        if not self.__objects.has(id):
            abort(404)

        self.__objects.delete(id)
        self.__objects.commit()

        return jsonify(result='True'), 200

app = Flask(__name__)

EntriesView.register(app)

@app.teardown_appcontext
def close_db(error):
    if g.db.connected: g.db.close()

@app.errorhandler(400)
def bad_request(error):
    return make_response(jsonify( { 'error': 'Bad request' } ), 400)

@app.errorhandler(404)
def not_found(error):
    return make_response(jsonify( { 'error': 'Not found' } ), 404)

def objects(entity):
    alias = entity.__name__.lower()
    if alias not in g.__objects:
        g.__objects[alias] = entity.objects(g.db)
    return g.__objects[alias]
	
def init():

    with app.app_context():
        g.db = DatabaseConnection('d22.db')
        g.__objects = {}
        g.objects = objects
        app.run()

if __name__ == '__main__':
    init()