how to read extjs data store

I want to read a particular value of an extjs data store and manipulate it locally. Response xml looks like :

<user><name>abc</name><surname>def</surname><book><bname>book1</bname></book></user>

My store will have just one user entry when response is received and i want to read ‘bname’ value. So far i have tried two approaches and both giving error.

approach1:

Ext.define('user', {
     extend: 'Ext.data.Model',
     fields: [ 'name', 'surname'],
     hasMany: {model: 'Book', name: 'book'},
      proxy: {
        type: 'rest',
         url : request,
         reader: { type: 'json', root: 'user'}
     }
 });
 Ext.define('Book', {
     extend: 'Ext.data.Model',
     fields: [ 'name'],
     belongsTo: 'user'
 });
 var userstore = Ext.create('Ext.data.Store', {
        model: "user"
 });
 incidentstore.load({
     callback: function() {
        var inc = userstore.first();
        var bk = inc.getBook();
        console.log(dev.get('bname'));
    }
});

Running above code gives error that ‘Ext.define is not a function’.

Approach2:

var proxy1 = new Jx.JxHttpProxyRest({
    url: request,
    api : {
            read : { headers : {     'Accept' : APP + '.abc.def.usermanage.user+json;version=1' } }
        }
    });

var reader = new Ext.data.XmlReader( {
    rootProperty : 'user',
    record : 'book',
    id : 'id',
}, [{ name : 'bname', mapping : 'book > bname'} ]);

var writer = new Ext.data.XmlWriter( {
    encode : false
});

var newstore = new Ext.data.Store( {
    id : 'book',
    restful : true,
    proxy : proxy1,
    remoteSort : true,
    reader : reader,
    writer : writer,
    autoload: true,
    listeners: {
        load: function() {
            console.log(newstore.data.first());
        }
    }
});
Ext.data.DataProxy.addListener('load', function(proxy, type, action, options, res) {
    console.log(res.responseText);
});
newstore.load( {
    params : { start : 0, limit : myPageSize },

});

Above code does not display anything on console.

I am new to extjs and not sure how i can access ‘bname’ value from response. It would be great if someone can help

Answer

Below code worked for me :

var newproxy = new Ext4.data.proxy.Rest({
    url : request,
    headers : {
        },
    reader :  {
        type : 'json',
        root : 'user.book'
    }});

 // Typical Store collecting the Proxy, Reader and Writer together.
 var newstore = Ext4.create('Ext4.data.Store', {
     id : 'book',
     fields: ['bname'],
     restful : true, // <-- This Store is RESTful
     autoLoad : true,
     proxy : newproxy
 });

var book;
newstore.load();
newstore.each(function(rec) {
    book= rec.get('bname');
});