Spree + Ember-Data is coming...

application_serializer.js

Backend.ApplicationSerializer = DS.RESTSerializer.extend({
  extractMeta: function(store, type, payload) {
    store.metaForType(type, {
      count: payload.count,
      currentPage: payload.current_page,
      pages: payload.pages
    });

    delete payload.count;
    delete payload.current_page;
    delete payload.pages;
  },

  keyForAttribute: function(attr) {
    return Ember.String.underscore(attr);
  },

  keyForRelationship: function(key, relationship) {
    key = Ember.String.singularize(key);

    if (relationship === 'hasMany') {
      return Ember.String.underscore(key) + '_ids';
    } else {
      return Ember.String.underscore(key) + '_id';
    }
  },

  serializeIntoHash: function(hash, type, record, options) {
    var root = Ember.String.underscore(type.typeKey);
    hash[root] = this.serialize(record, options);
  }
});

order.js

Backend.Order = DS.Model.extend({
  // ---------------------------------------------------------
  // Relationships
  // ---------------------------------------------------------
  
  billAddress: DS.belongsTo('address'),
  shipAddress: DS.belongsTo('address'),

  // ---------------------------------------------------------
  // Attributes
  // ---------------------------------------------------------

  number:    DS.attr('string'),
  itemTotal: DS.attr('number'),
  state:     DS.attr('string'),
  total:     DS.attr('number')
});

order_serializer.js

Backend.OrderSerializer = Backend.ApplicationSerializer.extend({
  extractSingle: function(store, type, payload, id, requestType) {
    var order = payload,
        billAddress = payload.bill_address,
        shipAddress = payload.ship_address,
        lineItems   = payload.line_items,
        payments    = payload.payments,
        shipments   = payload.shipments,
        adjustments = payload.adjustments;
        
    delete order.bill_address;
    delete order.ship_address;
    delete order.line_items;
    delete order.payments;
    delete order.shipments;
    delete order.adjustments;
    
    order.bill_address_id = billAddress.id;
    order.ship_address_id = shipAddress.id;
    order.line_item_ids   = lineItems.mapBy('id');
    order.payment_ids     = payments.mapBy('id');
    order.shipment_ids    = shipments.mapBy('id');
    order.adjustment_ids  = adjustments.mapBy('id');
    
    payload = {
      order: order,
      addresses: [billAddress, shipAddress],
      line_items: lineItems
      // payments: payments,
      // shipments: shipments,
      // adjustments: adjustments
    };

    return this._super(store, type, payload, id, requestType);
  },
  
  normalizeId: function(hash) {
    hash.id = hash.number;
  }
});