Question

I use rich domain model in my app. The basic ideas were taken there. For example I have User and Comment entities. They are defined as following:

<?php
class Model_User extends Model_Abstract {

    public function getComments() {
        /**
        * @var Model_Mapper_Db_Comment
        */
        $mapper = $this->getMapper();
        $commentsBlob = $mapper->getUserComments($this->getId());
        return new Model_Collection_Comments($commentsBlob);
    }

}

class Model_Mapper_Db_Comment extends Model_Mapper_Db_Abstract {

    const TABLE_NAME = 'comments';

    protected $_mapperTableName = self::TABLE_NAME;

    public function getUserComments($user_id) {
        $commentsBlob = $this->_getTable()->fetchAllByUserId((int)$user_id);
        return $commentsBlob->toArray();
    }
}

class Model_Comment extends Model_Abstract {

}
?>

Mapper’s getUserComments function simply returns something like:

return $this->getTable->fetchAllByUserId($user_id)

which is array. fetchAllByUserId accepts $count and $offset params, but I don’t know to pass them from my Controller to this function through model without rewriting all the model code.

So the question is how can I organize pagination through model data (getComments). Is there a “beatiful” method to get comments from 5 to 10, not all, as getComments returns by default.

Answer 1

Here is my solution:

class Model_Mapper_Db_Comment extends Model_Mapper_Db_Abstract {

    public function getUserCommentsPaginator($user_id) {
        $select = $this->_getTable()->select()->where('user_id = ?', (int)$user_id);
        $paginator = Zend_Paginator::factory($select, 'DbSelect');
        return $paginator;
    }
} 

class Model_User extends Model_Abstract implements Zend_Auth_Adapter_Interface {

    public function getCommentsPaginator() {
        $paginator = $this->getMapper(null, 'Comment')->getUserCommentsPaginator($this->id);
        $paginator->setFilter(new App_Filter_Array_Collection('Model_Collection_Comments'));
        return $paginator;
    }
}

Model requests Zend_Paginate object with prepared query based on user_id provided from Model. Then Model added filter to Zend_Paginate object to make it compatible with other Model methods (return Model_Collection classes, not arrays). All other pagination parameters are set in controller (page, the number of items per page, etc.).

Thet’s how I had separated storage, business and control logic in my application.