Why doesn't Ext.create('Model', ...) load associated model data?

[ykey]

I am having trouble loading associations through Ext.create. The following works fine when data is retrieved through a server proxy. However when the same data is loaded through Ext.create no associations are created.

The UI component depends on the nested stores and I would like to have default data available if the AJAX call fails or times out and for testing purposes.

Ext.define('Server', {
        extend: 'Ext.data.Model',
        idProperty: 'name',
        fields: [
            'name'
        ],
        
        hasMany: {
            model: 'Container', 
            name: 'containers'
        }
    });
    
    Ext.define('Container', {
        extend: 'Ext.data.Model',
        idProperty: 'name',
        fields: [
            'name'
        ]
    });        
    
    var sys = Ext.create('Server', {
        "name": "Server 1",
        "containers": [
            {
                "name": "A"
            },
            {
                "name": "B"
            },
            {
                "name": "C"
            }
        ]
    });
    
    console.log(sys); // Has 3 containers in the data field
    console.log(sys.containers());  // Has 0 records

[skirtle]

I agree that what you're trying to do appears sensible but it doesn't work. My guess is that associations are handled at the reader level and using Ext.create() skips that. It seems very counter-intuitive to me.

It took me quite a while to find a way of doing it that actually worked. Maybe there's a better way but this is what I came up with:

var reader = Ext.create('Ext.data.reader.Json', {
    model: 'Server'
});

var resultSet = reader.read({
    "name": "Server 1",
    "containers": [
        ...
    ]
});

var sys = resultSet.records[0];

All feels a bit yucky to me. I don't see anything there that couldn't be done implicitly in the model's constructor.

[devnullable]

I feel your pain guys. I was just wondering what's going on when associations are not loaded on Ext.create. Working on anything more "complex" than in examples, like a form with grids of associated model data is really frustrating experience. Build JSON by hand for saving primary model AND association models in same atomic AJAX request and then try to figure out how to load back response again...

[skirtle]

I've got this on my list of ExtJS 4.0 issues. I believe 4.1 addresses a lot of the shortcomings of 4.0 so I'm waiting for that release before I throw in a 'feature request' for this.

[mberrie]

Is there a bug report for this? I wouldn't expect 4.1 to fix an issue just because it is obvious that a feature is incomplete.

[skirtle]

I've seen comments from the Sencha devs that 4.1 will improve the data model, particularly associations. I don't know the details but I can't be bothered spending hours filing reports on issues until I know what's in 4.1.

I think the word bug may be a little strong in this case.

[Sébastien.Volle]

From what I've seen in 4.1 RC3, Ext.create('Model', ...) or new Model(...) still does not create association data in the Model instance. One still have to go through a reader for the associated data to be built.

Is there any plan for adding that in 4.1 GA? When instanciating a model instance, when all the required data is provided, I don't see why association data should not be there in the instance.

[gjuggler]

I've started running into this problem too.

It seems silly that associations can be loaded from serialized formats via the JSON and XML reader classes, but not from an in-memory data structure via the standard Ext.create() call. It's an unfortunate oversight in the API design.

I'd love to see this fixed in a future release!

[dougi]

i thought first that it was a bug on my side but it's worst. Can we expect a correction soon?

[jcervenka]

This works:
http://stackoverflow.com/questions/10104739/populating-associated-models-with-nested-json