Dataprovider For Related Activerecord Models

Yii 1.1 General Discussion
1

Is there an easy way to construct a dataprovider that returns objects related to another object?

I’m basically looking for the simplest version of this function:




/**

 * @param CActiveRecord $model        The primary model whose relations the provider will retrieve

 * @param string        $relationName The name of the relation we want to retrieve

 * @return CActiveDataProvider Provider that returns the related models

 **/

public function getRelationProvider($model, $relationName);

I do not want to return an array of related objects. Some instances may have thousands of related objects and I’m concerned about performance issues. (Sidenote: is that a valid concern? Should I just use CArrayDataProvider?)

I have considered this solution but it seems somewhat complicated:

[list=1]

[*]Parse the relation declaration into a criteria object

[*]Merge that criteria with the DbCriteria of an instance of the related model

[*]Construct a dataprovider using the updated instance

[/list]

I’d like to avoid that if possible. Any ideas/patterns for solving this problem?

2

Also looking for this. Please let me now if you come up with any realisation.

I have another realisation idea.

Make AdapterForRelationDataprovider with "model" property.

Set AdapterForRelationDataprovider->model=your model;

Set AdapterForRelationDataprovider->relationName= name of relation which you need

Set AdapterForRelationDataprovider->relationParams= base params for filtering relations

Override findAll() method, so it could call your model->getRelated(…) with limit in params (add offset and limit to base params via CMap::merge).

Voila!

3

Hi there,

I’m curious about what use case you have in your mind.

Is it something that you can not do with the data provider of the related model itself?

4

Yes, I’m making it for general case.

I have controller for viewing any model, by pk, or list of pks, or scope, or list of scopes, or by relation from another model, etc.

For example if I click "related orderedProducts" I get list of 17 related items (depending on scenario and context view of model(s) can be modified).

There many models with many different relations + there will be new models in future, I don’t want to make changes every time. So I need realisation for general case.