Controller.php

<?php

return Response::json(new SettingTemplate($data));

SettingTemplate.php

<?php

class SettingTemplate extends Template
{

    /**
     * Prepare the data to retreive.
     *
     * @return void
     */
    public function prepareData()
    {
        $this->setAttribute('key');
        $this->setAttribute('value');
        $this->setAttribute('created_at');
        $this->setAttribute('updated_at');
    }

}

Template.php

<?php

use Illuminate\Database\Eloquent\Model;
use DateTime;

abstract class Template
{

    /**
     * The model.
     *
     * @var Model
     */
    protected $model;

    /**
     * The attributes.
     *
     * @var array
     */
    protected $attributes;

    /**
     * Create a new instance.
     *
     * @param  Model $model
     * @return void
     */
    public function __construct(Model $model)
    {
        $this->model = $model;

        $this->prepareData();
    }

    /**
     * Return the model.
     *
     * @return Model
     */
    public function getModel()
    {
        return $this->model;
    }

    /**
     * Prepare the data to retreive.
     *
     * @return void
     */
    public function prepareData()
    {}

    /**
     * Get an attribute from the template.
     *
     * @param  string  $key
     * @return mixed
     */
    public function getAttribute($key)
    {
        if (isset($this->$key)) {
            return $this->$key;
        }

        return '';
    }

    /**
     * Set a given attribute on the template from model.
     *
     * @param  string  $key
     * @param  mixed  $value
     * @return void
     */
    public function setAttribute($key, $value = null)
    {
        if (is_null($value)) {
            $value = $this->model->$key;
        }

        if ($value instanceof DateTime) {
            $value = $value->format('c');
        }

        $this->$key = $value;

        unset($value);
    }

    /**
     * Dynamically retrieve attributes on the template.
     *
     * @param  string  $key
     * @return mixed
     */
    public function __get($key)
    {
        return $this->getAttribute($key);
    }

}