Customshipping.php

<?php

namespace uafrica\Customshipping\Model\Carrier;

use Magento\Framework\App\Config\ScopeConfigInterface;
use Magento\Framework\DataObject;
use Magento\Shipping\Model\Carrier\AbstractCarrier;
use Magento\Shipping\Model\Carrier\CarrierInterface;
use Magento\Shipping\Model\Rate\ResultFactory;
use Magento\Quote\Model\Quote\Address\RateResult\ErrorFactory;
use Magento\Quote\Model\Quote\Address\RateResult\Method;
use Magento\Quote\Model\Quote\Address\RateResult\MethodFactory;
use Magento\Quote\Model\Quote\Address\RateRequest;
use Psr\Log\LoggerInterface;
use Magento\Framework\Controller\Result\JsonFactory;
use Magento\Framework\HTTP\Client\CurlFactory;

/**
 * @category   uafrica
 * @package    uafrica_Customshipping
 * @author     info@bob.co.za
 * @website    https://www.bob.co.za
 */
class Customshipping extends AbstractCarrier implements CarrierInterface
{
    /** Tracking Endpoint */
    const TRACKING = 'https://api.dev.ship.uafrica.com/tracking?channel=localhost&tracking_reference=';
    /*** RATES API Endpoint*/
    const RATES_ENDPOINT = 'https://8390956f-c00b-497d-8742-87b1d6305bd2.mock.pstmn.io/putrates';

    /**
     * Carrier's code
     *
     * @var string
     */
    protected $_code = 'uafrica';

    /**
     * Whether this carrier has fixed rates calculation
     *
     * @var bool
     */
    protected $_isFixed = false;

    /**
     * @var ResultFactory
     */
    protected $_rateResultFactory;

    /**
     * @var MethodFactory
     */
    protected $_rateMethodFactory;

    /**
     * @var \Magento\Framework\Controller\Result\JsonFactory
     */
    protected $jsonFactory;

    /**
     * @var \Magento\Framework\HTTP\Client\Curl
     */
    protected $curl;


    /**
     * @param \Magento\Framework\Controller\Result\JsonFactory $jsonFactory
     */

    /**