The source code

    /**
     * @class Ext.data.DirectStore
     * @extends Ext.data.Store
     * <p>Small helper class to create an {@link Ext.data.Store} configured with an
     * {@link Ext.data.DirectProxy} and {@link Ext.data.JsonReader} to make interacting
     * with an {@link Ext.Direct} Server-side {@link Ext.direct.Provider Provider} easier.
     * To create a different proxy/reader combination create a basic {@link Ext.data.Store}
     * configured as needed.</p>
     *
     * <p><b>*Note:</b> Although they are not listed, this class inherits all of the config options of:</p>
     * <div><ul class="mdetail-params">
     * <li><b>{@link Ext.data.Store Store}</b></li>
     * <div class="sub-desc"><ul class="mdetail-params">
     *
     * </ul></div>
     * <li><b>{@link Ext.data.JsonReader JsonReader}</b></li>
     * <div class="sub-desc"><ul class="mdetail-params">
     * <li><tt><b>{@link Ext.data.JsonReader#root root}</b></tt></li>
     * <li><tt><b>{@link Ext.data.JsonReader#idProperty idProperty}</b></tt></li>
     * <li><tt><b>{@link Ext.data.JsonReader#totalProperty totalProperty}</b></tt></li>
     * </ul></div>
     *
     * <li><b>{@link Ext.data.DirectProxy DirectProxy}</b></li>
     * <div class="sub-desc"><ul class="mdetail-params">
     * <li><tt><b>{@link Ext.data.DirectProxy#directFn directFn}</b></tt></li>
     * <li><tt><b>{@link Ext.data.DirectProxy#paramOrder paramOrder}</b></tt></li>
     * <li><tt><b>{@link Ext.data.DirectProxy#paramsAsHash paramsAsHash}</b></tt></li>
     * </ul></div>
     * </ul></div>
     *
     * @xtype directstore
     *
     * @constructor
     * @param {Object} config
     */
    Ext.data.DirectStore = Ext.extend(Ext.data.Store, {
        constructor : function(config){
            // each transaction upon a singe record will generate a distinct Direct transaction since Direct queues them into one Ajax request.
            var c = Ext.apply({}, {
                batchTransactions: false
            }, config);
            Ext.data.DirectStore.superclass.constructor.call(this, Ext.apply(c, {
                proxy: Ext.isDefined(c.proxy) ? c.proxy : new Ext.data.DirectProxy(Ext.copyTo({}, c, 'paramOrder,paramsAsHash,directFn,api')),
                reader: (!Ext.isDefined(c.reader) && c.fields) ? new Ext.data.JsonReader(Ext.copyTo({}, c, 'totalProperty,root,idProperty'), c.fields) : c.reader
            }));
        }
    });
    Ext.reg('directstore', Ext.data.DirectStore);