ExtJS 4.1 - 在Model.Save()响应中返回关联数据

Question

我很好奇为什么Model.save()响应结果集中包含的记录没有正确返回更新的关联数据,尽管服务器响应中包含更新的数据...

示例模型和商店定义:

Ext.define("App.model.test.Parent",{
    extend: 'Ext.data.Model',
    requires: ['App.model.test.Child'],
    fields: [
            {name: 'id', type: 'int' },
            {name: 'name', type: 'string'},
            {name: 'kids', type: 'auto', defaultValue: []}
    ],
    idProperty: 'id',

    hasMany: [{
            foreignKey: 'parent_id',
            model: 'App.model.test.Child', 
            associationKey: 'kids',
            name: 'getKids'   
    }],

    proxy: {
        type: 'ajax',
        api : {
            create: '/service/test/create/format/json',
            read : '/service/test/read/format/json',
            update : '/service/test/update/format/json'
        },

        reader: {
            idProperty      : 'id',
            type            : 'json',
            root            : 'data',        
            successProperty : 'success',       
            messageProperty : 'message'
        },

        writer: {
            type            : 'json',
            writeAllFields  : true
        }
    }
});

Ext.define("App.model.test.Child",{
    extend: 'Ext.data.Model',
    fields: [
        {name: 'id', type: 'int' },
        {name: 'name', type: 'string'},
        {name: 'parent_id', type: 'int'}
    ]
});

Ext.define("App.store.test.Simpson",{
    storeId: 'TheSimpsons',
    extend: 'Ext.data.Store',
    model : 'App.model.test.Parent',
    autoLoad: true,
    autoSync: false
});

应用程序服务器READ使用单个模型及其关联数据对代理请求的响应.这是所有工作的hunky dory!

服务器对READ请求的响应

{
"data":{
    "id":1,
    "name":"Homer Simpson",
    "children":{
        "1":{
            "id":1,
            "name":"Bart Simpson"
        },
        "2":{
            "id":2,
            "name":"Lisa Simpson"
        },
        "3":{
            "id":3,
            "name":"Maggie Simpson"
        }
    }
},
"success":true,
"message":null
}

到目前为止,一切都按计划进行......

store = Ext.create("App.store.test.Simpson");
homer = store.getById(1);
kids  = homer.getKids().getRange();
console.log("The Simpson Kids", kids);  // [>constructor, >constructor, >constructor]

不受欢迎的行为开始时有保存和更新请求

这是我对UPDATE请求的测试响应...

/** Server UPDATE Response */
{
"data":{
    "id":1,
    "name":"SAVED Homer Simpson",
    "kids":[{
        "id":1,
        "name":"SAVED Bart Simpson",
        "parent_id":1
    },{
        "id":2,
        "name":"SAVED Lisa Simpson",
        "parent_id":1
    },{
        "id":3,
        "name":"SAVED Maggie Simpson",
        "parent_id":1
    }]
},
"success":true,
"message":null
}


/** Will call proxy UPDATE, response is above */
homer.save({
    success: function(rec, op){
        var savedRec = op.getRecords().pop(),
            kidNames = '';
        console.log(savedRec.get('name')); // SAVED Homer Simpson = CORRECT!
        Ext.each(savedRec.getKids().getRange(), function(kid){
            kidNames += kid.get('name') + ", ";
        });
        console.log(kids); 
        //Outputs: Bart Simpson, Lisa Simpson, Maggie Simpson = WRONG!!
    }
})

我注意到,如果我检查服务器返回的记录,生成的Association Store(即getKidsStore)包含的记录是原始记录,即它们的名称中没有"SAVED".kids但是,返回记录的属性确实包含正确的数据.

如果我正确理解了该问题,那就是Ext.data.reader.Reader没有正确地使用.save()响应中包含的关联数据更新关联的存储.如果是这样,在我看来,这是非常不直观的,因为我期望与处理store.load()请求的读者相同的行为并填充生成的关联存储开始.

任何人都能指出我在实现我追求的行为方面的正确方向吗？

免责声明:此处提出了同样的问题:ExtJs 4 - 在记录保存时加载嵌套数据,但没有响应.我觉得我的问题要更加彻底......

编辑:我已经在Sencha论坛上发布了这个问题:http://www.sencha.com/forum/showthread.php？ 270336-Associated IPv-in-Model.save()-Response

编辑(2013年8月23日):我用一个完整的例子重新写了这篇文章,以及其他发现......

Answer 1

我发现了问题,或者更确切地说,混淆在于getRecords()方法Ext.data.Operation.此方法返回"将返回操作的初始配置记录,尽管代理可能会在初始化操作后的某个时刻修改这些记录的数据." 根据文件.

这是相当令人困惑的IMO,因为返回的记录确实已更新,但生成的关联存储,因此关联的数据,不是!这是导致我混淆的原因,似乎记录包含来自应用程序服务器的更新数据,但事实并非如此.

为了帮助我简单地从响应中获取完全更新的数据,我已经在Ext.data.Operation类中添加了一个方法...我刚刚编写了这个方法并且没有测试它,而不是确保我正在寻找的功能,所以使用风险自负!

请记住,我没有调用store.sync(),而是实例化模型并调用model.save()方法,因此我的resultSet通常只包含一条记录...

Ext.override(Ext.data.Operation,{
    getSavedRecord: function(){
        var me = this, // operation
            resultSet = me.getResultSet();

        if(resultSet.records){
            return resultSet.records[0];
        }else{
            throw "[Ext.data.Operation] EXCEPTION: resultSet contains no records!";
        }

    }
});

现在我能够实现我追求的功能......

// Get the unsaved data
store = Ext.create('App.store.test.Simpson');
homer = store.getById(1);
unsavedChildren = '';

Ext.each(homer.getKids().getRange(), function(kid){
    unsavedChildren += kid.get('name') + ",";
});

console.log(unsavedChildren); // Bart Simpson, Lisa Simpson, Maggie Simpson

// Invokes the UPDATE Method on the proxy
// See original post for server response
home.save({
    success: function(rec, op){
        var savedRecord = op.getSavedRecord(), // the magic! /sarcasm
            savedKids   = '';

        Ext.each(savedRecord.getKids().getRange(), function(kid){
            savedKids += kid.get('name') + ',';
        });

        console.log("Saved Children", savedKids);

        /** Output is now Correct!!
            SAVED Bart Simpson, SAVED Lisa Simpson, SAVED Maggie Simpson
          */
    }
});

编辑12/10/13我还添加了一个方法Ext.data.Model,我调用updateTo它来处理将记录更新到提供的记录,该记录也处理关联.我将它与上述getSavedRecord方法结合使用.请注意,这不会处理任何belongsTo关联,因为我不在我的应用程序中使用它们,但该功能很容易添加.

/**
 * Provides a means to update to the provided model, including any associated data
 * @param {Ext.data.Model} model The model instance to update to. Must have the same modelName as the current model
 * @return {Ext.data.Model} The updated model
 */
updateTo: function(model){
    var me = this,
    that = model,
    associations = me.associations.getRange();

    if(me.modelName !== that.modelName)
    throw TypeError("updateTo requires a model of the same type as the current instance ("+ me.modelName +"). " + that.modelName + " provided.");

    // First just update the model fields and values
    me.set(that.getData());

    // Now update associations
    Ext.each(associations, function(assoc){
    switch(assoc.type){
        /**
         * hasOne associations exist on the current model (me) as an instance of the associated model.
         * This instance, and therefore the association, can be updated by retrieving the instance and
         * invoking the "set" method, feeding it the updated data from the provided model.
         */
        case "hasOne":
            var instanceName  = assoc.instanceName,
                currentInstance = me[instanceName],
                updatedInstance = that[instanceName];

             // Update the current model's hasOne instance with data from the provided model
             currentInstance.set(updatedInstance.getData());

            break;

        /** 
         * hasMany associations operate from a store, so we need to retrieve the updated association
         * data from the provided model (that) and feed it into the current model's (me) assocStore
         */
        case "hasMany":
            var assocStore = me[assoc.storeName],
                getter     = assoc.name,
                newData    = that[getter]().getRange();

            // Update the current model's hasMany association store with data from the provided model's hasMany store
            assocStore.loadData(newData);
            break;

        // If for some reason a bogus association type comes through, throw a type error
        // At this time I have no belongsTo associations in my application, so this TypeError
        // may one day appear if I decide to implement them.
        default:
            throw TypeError("updateTo does not know how to handle association type: " + assoc.type);
            break;
    }
    });

    // Commit these changes
    me.commit();

    return me;
}

所以基本上我做这样的事情(这理论上会在订单控制器中)

doSaveOrder: function(order){
    var me = this,                       // order controller 
        orderStore = me.getOrderStore(); // magic method

    // Save request
    order.save({
        scope: me,
        success: function(responseRecord, operation){ 
            // note: responseRecord does not have updated associations, as per post
            var serverRecord = operation.getSavedRecord(),
                storeRecord  = orderStore.getById(order.getId());

            switch(operation.action){
                case 'create':
                    // Add the new record to the client store
                    orderStore.add(serverRecord);
                break;

                case 'update':
                    // Update existing record, AND associations, included in server response
                    storeRecord.updateTo(serverRecord);
                break;
            }
        }
    });
}

我希望这可以帮助那些像我一样困惑的人!