curl --data "name=t-shirt&description=Star Trek&price=8.99&user=test1" -H "Accept: application/json" https://mywebsite.appspot.com/product

{"description": "Star Trek", "price": 8.9900000000000002, "name": "t-shirt", "user": "test1", "key": 5206065687822336}

from google.appengine.ext import ndb

class Model(ndb.Model):
    def to_dict(self):
        d = super(Model, self).to_dict()
        d['key'] = self.key.id()
        return d

class User(Model):
    username = ndb.StringProperty(required=True)
    password = ndb.StringProperty(required=True)

class Product(Model):
    name = ndb.StringProperty(required=True)
    description = ndb.StringProperty(required=True)
    price = ndb.FloatProperty()
    color = ndb.StringProperty()
    size = ndb.StringProperty()
    user = ndb.StringProperty(required=True)

class Sales(Model):
    products = ndb.KeyProperty(repeated=True)
    datetime = ndb.DateTimeProperty(required=True)
    quantity = ndb.IntegerProperty(repeated=True)
    product_cost = ndb.FloatProperty(repeated=True)
    total_cost = ndb.FloatProperty()
    latitude = ndb.FloatProperty()
    longitude = ndb.FloatProperty()
    user = ndb.KeyProperty(required=True)


    def to_dict(self):
        d = super(Sales, self).to_dict()
        d['products'] = [i.id() for i in d['products']]
        return d

import webapp2
from google.appengine.ext import ndb
import models
import json

class Product(webapp2.RequestHandler):
    #Create a Product entity
    def post(self):
        if 'application/json' not in self.request.accept:
            self.response.status = 406
            self.response.status_message = 'Not acceptable, API only supports application/json MIME type.'
            return
        new_product = models.Product()
        name = self.request.get('name', default_value=None)
        description = self.request.get('description', default_value=None)
        price = self.request.get('price', default_value=0)
        color = self.request.get('color', default_value=None)
        size = self.request.get('size', default_value=None)
        user = self.request.get('user', default_value=None)

        if name:
            new_product.name = name
        else:
            self.response.status = 400
            self.response.status_message = 'Invalid request, name required'
        if description:
            new_product.description = description
        else:
            self.response.status = 400
            self.response.status_message = 'Invalid request, description required'
        if price:
            new_product.price = float(price)
        if color:
            new_product.color = color
        if size:
            new_product.size = size
        if user:
            new_product.user = user
        else:
            self.response.status = 400
            self.response.status_message = 'Invalid request, username required'
        key = new_product.put()
        out = new_product.to_dict()
        self.response.write(json.dumps(out))
        return

    #Return an Product entity
    def get(self, **kwargs):
        if 'application/json' not in self.request.accept:
            self.response.status = 406
            self.response.status_message = 'Not acceptable, API only supports application/json MIME type.'
            self.response.write(self.response.status_message)
            return
        #Return selected product details
        if 'id' in kwargs:
            out = ndb.Key(models.Product, int(kwargs['id'])).get().to_dict()
            self.response.write(json.dumps(out))
        #Return all product ids
        else:
            q = models.Product.query()
            keys = q.fetch(keys_only=False)
            results = {x.key.id() : x.to_dict() for x in keys}
            self.response.write(json.dumps(results))