ltsecurityinc/app/code/JR/NetSuite/Lib/Oauth.php

<?php
namespace JR\NetSuite\Lib;

use Magento\Framework\App\Config\ScopeConfigInterface;
use Magento\Store\Model\ScopeInterface;
use Magento\Store\Model\StoreManagerInterface;

class Oauth
{
    const SIGNATURE_METHOD_HMACSHA256 = 'HMAC-SHA256';
    const OAUTH_SCRIPT = 'jr_netsuite/apidetail/script';
    const OAUTH_VERSION = '1.0';
    const NONCE_STRING = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ';
    const XML_PATH_OAUTH_URL = 'jr_netsuite/apidetail/api_url';
    const XML_PATH_OAUTH_REALM = 'jr_netsuite/apidetail/oauth_realm';
    const XML_PATH_OAUTH_CONSUMER_KEY = 'jr_netsuite/apidetail/oauth_consumer_key';
    const XML_PATH_OAUTH_CONSUMER_SECRET = 'jr_netsuite/apidetail/oauth_consumer_secret';
    const XML_PATH_OAUTH_TOKEN = 'jr_netsuite/apidetail/oauth_token';
    const XML_PATH_OAUTH_TOKEN_SECRET = 'jr_netsuite/apidetail/oauth_token_secret';

    /**
     * @var StoreManagerInterface
     */
    protected $storeManager;

    /**
     * @var ScopeConfigInterface
     */
    protected $scopeConfig;

    /**
     * @var string
     */
    protected $script;

    /**
     * @param StoreManagerInterface $storeManager
     * @param ScopeConfigInterface $scopeConfig
     **/

    public function __construct(
        StoreManagerInterface $storeManager,
        ScopeConfigInterface $scopeConfig
    ) {
        $this->scopeConfig = $scopeConfig;
        $this->storeManager = $storeManager;
    }

    /**
     * consumer key
     * @return string
     */
    public function getConsumerKey()
    {
        return $this->getConfigValue(self::XML_PATH_OAUTH_CONSUMER_KEY);
    }

    /**
     * consumer Secret
     * @return string
     */
    public function getConsumerSecret()
    {
        return $this->getConfigValue(self::XML_PATH_OAUTH_CONSUMER_SECRET);
    }

    /**
     * Token access key
     * @return string
     */
    public function getToken()
    {
        return $this->getConfigValue(self::XML_PATH_OAUTH_TOKEN);
    }

    /**
     * Token Secret
     * @return string
     */
    public function getTokenSecret()
    {
        return $this->getConfigValue(self::XML_PATH_OAUTH_TOKEN_SECRET);
    }

    /**
     * Token Secreat
     * @return string
     */
    public function getRealm()
    {
        return $this->getConfigValue(self::XML_PATH_OAUTH_REALM);
    }

    /**
     * Set Token Script
     * @return string
     */
    public function setScript($script)
    {
        $this->script = $script;
    }

    /**
     * Token script
     * @return string
     */
    public function getScript()
    {
        if ($this->script)  {
            return $this->script;
        }
        return $this->getConfigValue(self::OAUTH_SCRIPT);
    }
    /**
     * Token Secreat
     * @return  string
     */
    public function getApiUrl()
    {
        return $this->getConfigValue(self::XML_PATH_OAUTH_URL);
    }
    /**
     * Calculate header for request
     * @return string
     */
    public function getOauthParams($method = 'POST')
    {
        $time = time();
        $nonce = rawurlencode($this->generateNonceString(11));
        $oauthparams = $this->getParamObject($nonce, $time);
        $baseString = $this->createBaseString($method, $oauthparams);
        $signature = $this->getSignature('sha256', $baseString);
        return $this->buildAuthorizationHeader($nonce, $time, $signature);
    }

    /**
     * Calculate signature for request
     * @return string
     */
    public function getSignature($algo, $baseString)
    {
        $key = rawurlencode($this->getConsumerSecret()) . '&' . rawurlencode($this->getTokenSecret());
        return rawurlencode(base64_encode(hash_hmac($algo, $baseString, $key, true)));
    }

    /**
     * Builds the Authorization header for a request
     * @return string
     */
    private function buildAuthorizationHeader($nonce, $time, $signature)
    {
        return 'OAuth realm="' . $this->getRealm() . '",oauth_consumer_key="' . $this->getConsumerKey() . '",oauth_token="' . $this->getToken() . '",oauth_signature_method="HMAC-SHA256",oauth_timestamp="' . $time . '",oauth_nonce="' . $nonce . '",oauth_version="1.0",oauth_signature="' . $signature . '"';
    }

    /**
     * Creates the Signature Base String.
     * The Signature Base String is a consistent reproducible concatenation of
     * the request elements into a single string. The string is used as an
     * input in hashing or signing algorithms.
     * @return string Returns the base string
     */

    private function createBaseString($method, $params)
    {
        $url = $this->getApiUrl();
        $query = http_build_query($params, '', '&', PHP_QUERY_RFC3986);

        return strtoupper($method)
            . '&' . rawurlencode($url)
            . '&' . rawurlencode($query);
    }
    /**
     * generating nonce value
     * @return string
     */
    public function generateNonceString($length = 11)
    {
        $characters = self::NONCE_STRING;
        $charactersLength = strlen($characters);
        $randomString = '';
        for ($i = 0; $i < $length; $i++) {
            $randomString .= $characters[rand(0, $charactersLength - 1)];
        }
        return $randomString;
    }

    /**
     * generating param value
     * @return array
     */
    public function getParamObject($nonce, $time)
    {
        return [
            'deploy' => 1,
            "oauth_consumer_key" => $this->getConsumerKey(),
            "oauth_nonce" => $nonce,
            "oauth_signature_method" => self::SIGNATURE_METHOD_HMACSHA256,
            "oauth_timestamp" => $time,
            "oauth_token" => $this->getToken(),
            "oauth_version" => self::OAUTH_VERSION,
            'script' => $this->getScript()
        ];
    }

    /**
     * get config value
     * @return string
     */
    public function getConfigValue($path)
    {
        $store = $this->storeManager->getStore()->getStoreId();
        $config_data = $this->scopeConfig->getValue($path, ScopeInterface::SCOPE_STORE, $store);
        return $config_data;
    }
}