Data model : Association getter returns undefined - extjs

Question

My problem consists of not being able to retrieve data through associations.
After running setup() from console i would expect firstTurbine.getPlant() to return the associated plant, yet it returns undefined.
I've spent alot of time looking for a solution I'm probably not looking the right place.
Relevant code is attached below:
Ext.regApplication({
name: "app",
launch: function() {
//app.views.viewport = new app.views.Viewport();
}
});
app.models.Plant = Ext.regModel("Plant", {
fields: [
{name: "id", type: "int"},
{name: "name", type: "string"},
{name: "notes", type: "auto"}
],
proxy: {type: 'localstorage', id:'plantStorage'}
});
app.models.Turbine = Ext.regModel("Turbine", {
fields: [
{name: "id", type: "int"},
{name: "plant_id", type: "int"},
{name: "name", type: "string"},
{name: "notes", type: "auto"}
],
proxy: {type: 'localstorage', id:'turbineStorage'},
belongsTo: 'Plant'
});
app.stores.plants = new Ext.data.Store({
model: "Plant",
autoLoad: true,
data : [
{id: 1, name: 'Plant1', notes: ["Note1", "Note2"]},
{id: 2, name: 'Plant2', notes: ["Note1", "Note2"]},
{id: 3, name: 'Plant3', notes: ["Note1", "Note2"]}
]
});
app.stores.turbines = new Ext.data.Store({
model: "Turbine",
autoLoad: true,
data: [
{id: 11, "plant_id": 1, name: "T41", notes: ["Turbine note 1", "Turbine note 2"]},
{id: 12, "plant_id": 1, name: "T13", notes: ["Turbine note 1", "Turbine note 2"]}
]
});
function setup(){
firstPlant = app.stores.plants.getAt(0);
if(!firstPlant){
firstPlant = Ext.ModelMgr.create({name:"TestPlant1", id: 1}, "Plant");
app.stores.plants.add(firstPlant);
app.stores.plants.sync();
}
firstTurbine = app.stores.turbines.getAt(0);
if(!firstTurbine){
firstTurbine = Ext.ModelMgr.create({name:"T31", id: 30, plant_id: 1}, "Turbine");
app.stores.turbines.add(firstTurbine);
app.stores.turbines.sync();
}
return {firstTurbine: firstTurbine, firstPlant: firstPlant};
}

Answer 1

The getter function created by the belongsTo association takes a callback function as argument. The callback function will have the related object as its first argument.
turbine.getPlant(function(Plant){
console.log(Plant);
});
I will attach a full working example since this have cost me alot of headache and might have aswell for others.
first the json data:
{
"plants": [{
"id": 1,
"name": "Plant1",
"notes": ["Note1", "Note2"]
}],
"turbines": [
{
"id": 11,
"plant_id": 1,
"name": "T41",
"notes": ["Turbine note 1", "Turbine note 2"]
}]
}
And the javascript:
Ext.regApplication({
name: "app",
launch: function() {}
});
app.models.Plant = Ext.regModel("Plant", {
fields: ["id", "name", "notes"],
proxy: {
type: 'ajax',
url: 'data.json',
reader: {
type: 'json',
root: 'plants'
}
}
});
app.models.Turbine = Ext.regModel("Turbine", {
fields: ["id", "plant_id", "name", "notes"],
proxy: {
type: 'ajax',
url: 'data.json',
reader: {
type: 'json',
root: 'turbines'
}
},
belongsTo: 'Plant'
});
app.stores.plants = new Ext.data.Store({
model: "Plant"
});
app.stores.turbines = new Ext.data.Store({
model: "Turbine",
autoLoad: {
callback: function(records) {
var turbine = records[0];
turbine.getPlant(function(Plant){
console.log(Plant);
});
}
}
});