Reusable relations cache mechanism issue

Question

Reusable relations cache mechanism issue

Anton Sokolov Sep '19

Created Sep '19	Last Reply Sep '19	Replies 1	Views 167	Votes 0

Anton Sokolov 723

Sep '19

Hello! Phalcon 3.4.0 I have two related models: UserSellerDealings as Sellers with reusable relation in UserSellerDealings

    $this->belongsTo(
            'sellerId',
            'Abka\\Business\\Models\\Sellers',
            'id',
            [
                'alias'      => 'Seller',
                'foreignKey' => [
                    'action'  => Relation::ACTION_RESTRICT,
                    'message' => 'Продавца не существует',
                ],
                'reusable'   => true,
            ]
        );

Then i run code

        $model = ModelsUserSellerDealings::findFirstById(17198);
        print_r($model->seller->property);   // see property value 'someValue'

        // then i update related records by raw query (or code from outside, another process, ets...) 
        $rawQuery = '
            UPDATE sellers
            SET property='newValue'
            WHERE id=:sellerId
        ';
        $this->db->query($rawQuery, ['sellerId' => $dealingsModel->seller->id]);

        print_r($model->seller->property);   // see property value 'someValue'

Expected behavior, I see the old value. If the "reusable" parameter is turned off, then we will see a new value. I studied the source code (Model and Manager) and saw that related data is stored in an associative array.

But if I create a new model, then the cache remains in it!

    $model = ModelsUserSellerDealings::findFirstById(17198);
    print_r($model->seller->property);   // see property value 'someValue'

I don’t understand how this happens. I use models in workers and have unpredictable behavior and risk of cache overflowIs. it possible to globally reset the cache of related models?

Anton Sokolov
723

Accepted
answer

Sep '19

Lajos Bencz, thanks! In the future I will use the data cache. Now i use only "reusable" feature for accelleration.

I looked in detail at the source and saw that the model manager has its own cache. Thus, there are two levels of cache. Since I have defined the model manager as a shared service, in the newly created models its cache becomes available. The problem was solved by clearing the cache in the worker when starting the next task:

$this->di->getShared('modelsManager')->clearReusableObjects();

Lajos Bencz · Answer 1 · 2019-09-23T03:04:20-07:00

$model = ModelsUserSellerDealings::findFirstById(17198);
print_r($model->seller->property);   // see property value 'someValue'

This line is working as expected, the ORM will recognize that the partiucar model had already been queried, and just restores it.

You could use the get<relation> syntax to manually set the cache lifetime:

https://docs.phalcon.io/3.4/en/db-models-cache.html

To query one record:

$model = ModelsUserSellerDealings::findFirst([
    'id = :id:',
    'bind' => ['id'=>17198],
    'cache' => [
        'lifetime' => 0,
    ],
]);

To query related records:


$model = ModelsUserSellerDealings::findFirstById(17198);
$property = $model->getSeller([
        'cache' => [
            'lifetime' => 0,
        ],
    ])->getProperty([
        'cache' => [
            'lifetime' => 0,
        ],
    ]);

(I've never tried this, could not even work....)

As for the cache overflow, I dont know if Phalcon handles any cache limit out-of-the-box. But you could always implement your own cache adapter, and limit the cache recrods from there.