Ember Data breaks when fetching JSON from Node + Express REST server - node.js

Question

I am trying to fetch JSON data from REST server built with Node.js and Express and then use it as a model in my Ember#Route.
The data I am trying to fetch:
var books = [
{ id: 98, author: 'Stanisław Lem', title: 'Solaris' },
{ id: 99, author: 'Andrzej Sapkowski', title: 'Wiedźmin' }
];
The model I use:
App.Book = DS.Model.extend({
id: DS.attr('number'),
author: DS.attr('string'),
title: DS.attr('string')
});
I set up the RESTAdapter this way:
App.ApplicationAdapter = DS.RESTAdapter.extend({
host: 'http://localhost:8080'
});
Mapping:
App.Router.map(function () {
this.resource("books");
});
My Route looks like this:
App.BooksRoute = Ember.Route.extend({
model: function () {
return this.store.find('book');
}
});
I am aware that ember-data follows certain convention when it comes to JSON files.
My server provides JSONs this way:
app.get('/books', function (request, response) {
console.log('In GET function ');
response.json({'books': books})
});
Then, after entering
http://localhost:8080/books
I get
{"books":[{"id":98,"author":"Stanisław Lem","title":"Solaris"},{"id":99,"author":"Andrzej Sapkowski","title":"Wiedźmin"}]}
but when I enter
http://localhost:8080/#/books
ember-data throws long error list that begins with:
"Error while processing route: books" "invalid 'in' operand record._attributes"
"ember$data$lib$system$model$attributes$$getValue#http://localhost:8080/static/ember-data.js:8176:1
ember$data$lib$system$model$attributes$$attr/<#http://localhost:8080/static/ember-data.js:8202:26
computedPropertySet#http://localhost:8080/static/ember.prod.js:11882:15
computedPropertySetWithSuspend#http://localhost:8080/static/ember.prod.js:11842:9
makeCtor/Class#http://localhost:8080/static/ember.prod.js:33887:17
...
and now I don't know what is wrong and how to fix this.

Answer 1

Looks like the mistake I made was in declaring model. ID attribute shouldn't be declared here, correct model looks like this:
App.Book = DS.Model.extend({
author: DS.attr('string'),
title: DS.attr('string')
});