Ember : Retrieve fixtures from attributes

I'm currently developing an application with ember cli where I want to draw shapes with svg and store them with the fixture adapter. The svg shapes are made of views to directly interact with them. The fact is that when I click on a shape I want to know on which one in my store I clicked, to then move them by dragging the mouse and update their coordinates.

Here is my view :

var click=false; // flag to indicate when shape has been clicked
var clickX, clickY; // stores cursor location upon first click
var moveX=0, moveY=0; // keeps track of overall transformation
var lastMoveX=0, lastMoveY=0;

export default Ember.View.extend({
    tagName: "rect",
    attributeBindings: ['x','y','width','height','stroke','stroke-width','fill'],
    width: "100",
    height: "150",
    stroke: "black",
    fill: "white",

    mouseDown: function(evt){
        var svg= Ember.$("svg");
        evt.preventDefault();
        click=true;
        clickX = evt.pageX - svg.offset().left;
        clickY = evt.pageY - svg.offset().top;
    },

    mouseMove: function(evt){
        evt.preventDefault();
        if(click){
            moveX= lastMoveX + (evt.pageX - clickX);
            moveY= lastMoveY + (evt.pageY - clickY);
            var x=Ember.$(evt.target).attr("x");
            var y=Ember.$(evt.target).attr("y");
            this.store.find('element',{'x':x, 'y':y}).then(function(element){
                element.set('x',moveX);
                element.set('y',moveY);
                element.save();
            });
        }
    },

    mouseUp: function(evt){
        click=false;
        lastMoveX = moveX;
        lastMoveY = moveY;
    },

    mouseLeave: function(evt){
        click=false;
        lastMoveX = moveX;
        lastMoveY = moveY;
    }
});

My model :

import DS from 'ember-data';

export default DS.Model.extend({
    text: DS.attr('string'),
    x: DS.attr('number'),
    y: DS.attr('number'),
    graph: DS.belongsTo('graph')
}).reopenClass({
    FIXTURES: []
});

In order to update my fixture I had to implement the queryFixtures function like this :

import DS from 'ember-data';
import Ember from 'ember';
import App from '../app';

export default DS.FixtureAdapter.extend({
  queryFixtures: function (fixtures, query, type) {
        if(type == App.Element ){
            var x= Ember.keys(query)[0];
            var y= Ember.keys(query)[1];
            var fixturesSorted = fixtures.filterBy(x,query[x]);
            return fixtures.filterBy(x,query[x]);
        }
    }
});

The problem is that I only get an undefined from this function. Maybe I implemented it wrong. But even if I put a console.log(fixtures) in this function, I've got nothing related to my models whereas they are displayed in my ember inspector.

Anyone with an idea ? Thanks !