如何克隆Ember Data记录，包括关系？ [英] How can I clone an Ember Data record, including relationships?

问题描述

我已经想到我可以克隆一个Ember Data记录并复制其属性，但是没有一个 belongsTo / hasMany 关系被克隆。如果我不知道有什么关系可以离开存在的关系，我可以这样做吗？

为了参考，这里是我已经这将克隆一个Ember Data记录的属性：

  var attributeKeys = oldModel.get（'constructor.attributes.keys.list'） ; 
 var newRecord = this.get（'store'）。createRecord（oldModel.constructor.typeKey）; 
 newRecord.setProperties（oldModel.getProperties（attributeKeys））; 
  

解决方案

对Daniel的 answer ，允许提供覆盖，并清除新记录的ID，以便安全。另外我也不想在克隆方法中调用 save ，而是将其留给调用者。

  DS.Model.reopen（{
 clone：function（overrides）{
 var model = this，
 attrs = model.toJSON（），
 class_type = model.constructor; 
 
 var root = Ember.String.decamelize（class_type.toString（）。split（'。'）[1]）; 
 
 / * 
 *需要用
 *实际模型实例替换belongsTo关联（id）
 * 
 *例如，如果belongsTo关联是项目，
 * json项目的价值将是：（project：project_id_1）
 *，这需要转换为（project：[projectInstance]）
 * / 
 this.eachRelationship（function（key，关系）{
 if（relationship.kind =='belongsTo'）{
 attrs [key] = model.get（key）; 
} 
 }）; 
 
 / * 
 *需要将新记录与旧版本分开。 
 * / 
删除attrs.id; 
 
 / * 
 *如果提供覆盖，应用覆盖。 
 * / 
 if（Ember.typeOf（overrides）==='object'）{
 Ember.setProperties（attrs，overrides）; 
} 
 
 return this.store.createRecord（root，attrs）; 
} 
}）; 
  

I've figured out that I can clone an Ember Data record and copy its Attributes, but none of the belongsTo/hasMany relationships are cloned. Can I do this somehow if I don't know what relationships would be possible, going off of the relationships that exist?

For reference, here is what I've got that will clone an Ember Data record's attributes:

var attributeKeys = oldModel.get('constructor.attributes.keys.list');
var newRecord = this.get('store').createRecord(oldModel.constructor.typeKey);
newRecord.setProperties(oldModel.getProperties(attributeKeys));

解决方案

A few improvements to Daniel's answer that allows providing overrides, and clears the id for new records, to be safe. Also I prefer not to call save within the clone method, but leave it up to the caller.

DS.Model.reopen({
    clone: function(overrides) {
        var model = this,
            attrs = model.toJSON(),
            class_type = model.constructor;

        var root = Ember.String.decamelize(class_type.toString().split('.')[1]);

        /*
         * Need to replace the belongsTo association ( id ) with the
         * actual model instance.
         *
         * For example if belongsTo association is project, the
         * json value for project will be:  ( project: "project_id_1" )
         * and this needs to be converted to ( project: [projectInstance] )
         */
        this.eachRelationship(function(key, relationship) {
            if (relationship.kind == 'belongsTo') {
                attrs[key] = model.get(key);
            }
        });

        /*
         * Need to dissociate the new record from the old.
         */
        delete attrs.id;

        /*
         * Apply overrides if provided.
         */
        if (Ember.typeOf(overrides) === 'object') {
            Ember.setProperties(attrs, overrides);
        }

        return this.store.createRecord(root, attrs);
    }
});

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