Helper Class Overview

The Helper class is a collection of static utility methods used throughout the myPOS IPC SDK. These include input validation, HTML sanitization, and array manipulation functions commonly required when handling API requests.

Class Information

Namespace: Mypos\IPC
File: Helper.php
Type: Static utility class

Method Summary

Method	Return Type	Description
`isValidEmail(string $email)`	`bool`	Validates an email address.
`isValidURL(string $url)`	`bool`	Validates a URL.
`isValidIP(string $ip)`	`bool`	Validates an IPv4 or IPv6 address.
`isValidName(string $name)`	`bool`	Checks if a customer name is valid.
`isValidAmount(float $amt)`	`bool`	Validates if the amount is a positive number.
`isValidCartQuantity(int $quantity)`	`bool`	Ensures quantity is a valid positive integer.
`isValidTrnRef(string $trnref)`	`bool`	Validates a transaction reference string.
`isValidOrderId(string $orderId)`	`bool`	Validates an order ID format.
`isValidOutputFormat(string $outputFormat)`	`bool`	Validates if the format is supported (`json`, `xml`, `post`).
`isValidCardNumber($cardNo)`	`bool`	Validates a card number using standard checks (Luhn algorithm, etc.).
`isValidCVC($cvc)`	`bool`	Validates the CVC code (3 or 4 digits).

HTML Utility Methods

Method	Return Type	Description
`escape(string $text)`	`string`	Escapes HTML special characters for safe output.
`unescape(string $text)`	`string`	Converts escaped HTML characters back to normal text.

Array Utility Methods

Method	Return Type	Description
`getArrayVal(array $array, mixed $key, string $default = '', bool $notEmpty = false)`	`mixed`	Returns value from associative array by key. Returns default if key is not found or empty (if `$notEmpty` is true).
`getValuesFromMultiDimensionalArray(array $array, array $values = [])`	`array`	Flattens a multi-dimensional array to a single array of values. Useful for signature generation.

Example Usage

Code Example

JSON

<?php
namespace Mypos\IPC;
/**
 * IPC Library helper functions
 */
class Helper
{
    private function __construct() { }
    /**
     * Validate email address
     *
     * @param string $email
     *
     * @return boolean
     */
    public static function isValidEmail($email)
    {
        return filter_var($email, FILTER_VALIDATE_EMAIL);
    }
    /**
     * Validate URL address
     *
     * @param string $url
     *
     * @return boolean
     */
    public static function isValidURL($url)
    {
        return filter_var($url, FILTER_VALIDATE_URL);
    }
    /**
     * Validate IP address
     *
     * @param string $ip
     *
     * @return boolean
     */
    public static function isValidIP($ip)
    {
        return filter_var($ip, FILTER_VALIDATE_IP);
    }
    /**
     * Validate customer names
     *
     * @param string $name
     *
     * @return boolean
     */
    public static function isValidName($name)
    {
        return preg_match("/^[a-zA-Z ]*$/", $name);
    }
    /**
     * Validate amount.
     *
     * @param float $amt
     *
     * @return boolean
     */
    public static function isValidAmount($amt)
    {
        return preg_match('/^(-)?[0-9]+(?:\.[0-9]{0,2})?$/', $amt);
    }
    /**
     * Validate if currency is acceptable by API
     *
     * @param string $currency ISO 4217 code
     *
     * @return boolean
     */
    public static function isValidCurrency($currency)
    {
        return in_array(strtoupper($currency), explode(';', Defines::AVL_CURRENCIES));
    }
    /**
     * Validate quantity
     *
     * @param int $quantity
     *
     * @return boolean
     */
    public static function isValidCartQuantity($quantity)
    {
        return is_int($quantity) && $quantity > 0;
    }
    /**
     * Validate transaction reference
     *
     * @param string $trnref
     *
     * @return boolean
     */
    public static function isValidTrnRef($trnref)
    {
        #TODO
        return true;
    }
    /**
     * Validate Order ID
     *
     * @param string $trnref
     *
     * @return boolean
     */
    public static function isValidOrderId($trnref)
    {
        #TODO
        return true;
    }
    /**
     * Validate output format
     *
     * @param string $outputFormat
     *
     * @return boolean
     */
    public static function isValidOutputFormat($outputFormat)
    {
        return in_array($outputFormat, [
            Defines::COMMUNICATION_FORMAT_XML,
            Defines::COMMUNICATION_FORMAT_JSON,
        ]);
    }
    /**
     * Validate card number
     *
     * @param $cardNo
     *
     * @return boolean
     */
    public static function isValidCardNumber($cardNo)
    {
        $cardNo = str_replace(" ", "", trim($cardNo));
        if ((!is_numeric($cardNo)) || (strlen($cardNo) > 19) || (strlen($cardNo) < 13)) {
            return false;
        }
        $sum = $dub = $add = $chk = 0;
        $even = 0;
        for ($i = strlen($cardNo) - 1; $i >= 0; $i--) {
            if ($even == 1) {
                $dub = 2 * $cardNo[$i];
                if ($dub > 9) {
                    $add = $dub - 9;
                } else {
                    $add = $dub;
                }
                $even = 0;
            } else {
                $add = $cardNo[$i];
                $even = 1;
            }
            $sum += $add;
        }
        return (($sum % 10) == 0);
    }
    /**
     * Validate card CVC
     *
     * @param $cvc
     *
     * @return boolean
     */
    public static function isValidCVC($cvc)
    {
        return (is_numeric($cvc) && strlen($cvc) == 3);
    }
    /**
     * Escape HTML special chars
     *
     * @param string $text
     *
     * @return string type
     */
    public static function escape($text)
    {
        $text = htmlspecialchars_decode($text, ENT_QUOTES);
        return htmlspecialchars($text, ENT_QUOTES);
    }
    /**
     * Unescape HTML special chars
     *
     * @param string $text
     *
     * @return string
     */
    public static function unescape($text)
    {
        return htmlspecialchars_decode($text, ENT_QUOTES);
    }
    /**
     * Return associative array element by key.
     * If key not found in array returns $default
     * If $notEmpty argument is TRUE returns $default even if key is found in array but the element has empty value(0, null, '')
     *
     * @param array $array
     * @param mixed $key
     * @param string $default
     * @param bool $notEmpty
     *
     * @return mixed
     */
    public static function getArrayVal($array, $key, $default = '', $notEmpty = false)
    {
        if (!is_array($array)) {
            return $default;
        }
        if ($notEmpty) {
            if (array_key_exists($key, $array)) {
                $val = trim($array[$key]);
                if (!empty($val)) {
                    return $val;
                }
            }
            return $default;
        } else {
            return array_key_exists($key, $array) ? $array[$key] : $default;
        }
    }
    /**
     * Returns one-dimensional array with all values from multi-dimensional array
     * Useful when create request signature where only array values matter
     *
     * @param array $array
     * @param array $values
     *
     * @return array
     */
    public static function getValuesFromMultiDimensionalArray($array, $values = [])
    {
        if (!is_array($array)) {
            return $values;
        }
        foreach ($array as $k => $v) {
            if (is_array($v)) {
                $values = self::getValuesFromMultiDimensionalArray($v, $values);
            } else {
                $values[] = $v;
            }
        }
        return $values;
    }
}

Use Cases

Use the Helper class to:

Clean and validate input data before building requests
Extract and flatten data structures
Prevent HTML injection in user-facing components
Ensure transaction fields meet formatting requirements