Merge pull request #5 from xendit/feature/luhn-validation

add luhn validation
xendit · Aug 31, 2018 · 0e2e5a1 · 0e2e5a1
2 parents 7c18842 + 9f69aa3
commit 0e2e5a1
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Showing 2 changed files with 24 additions and 2 deletions.
diff --git a/package.json b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "xendit-js-node",
-  "version": "0.2.0",
+  "version": "0.3.0",
   "description": "JS client library for tokenizing credit cards as node modules",
   "main": "./src/xendit.js",
   "repository": {

diff --git a/src/utils/credit_card_util.js b/src/utils/credit_card_util.js
@@ -18,7 +18,8 @@ CreditCardUtil.isCreditCardNumberValid = function (creditCardNumber) {
     return NUMBER_REGEX.test(creditCardNumber) &&
         creditCardNumber.length >= 12 &&
         creditCardNumber.length <= 19 &&
-        CreditCardUtil.getCardType(creditCardNumber) !== null;
+        CreditCardUtil.getCardType(creditCardNumber) !== null &&
+        CreditCardUtil.isValidLuhnNumber(creditCardNumber);
 };
 
 CreditCardUtil.isCreditCardExpirationDateValid = function (cardExpirationMonth, cardExpirationYear) {
@@ -51,6 +52,27 @@ CreditCardUtil.isCreditCardCVNValidForCardType = function (creditCardCVN, cardNu
     }
 };
 
+CreditCardUtil.isValidLuhnNumber = function (cardNumber) {
+    var sum = 0, bEven = false;
+	cardNumber = cardNumber.replace(/\D/g, '');
+
+	for (var n = cardNumber.length - 1; n >= 0; n--) {
+		var cDigit = cardNumber.charAt(n);
+		var nDigit = parseInt(cDigit, 10);
+
+		if (bEven) {
+			if ((nDigit *= 2) > 9) {
+                nDigit -= 9;
+            }
+		}
+
+		sum += nDigit;
+		bEven = !bEven;
+	}
+
+	return (sum % 10) === 0;
+};
+
 CreditCardUtil.getCardType = function (cardNumber) {
     if (cardNumber.indexOf('4') === 0)  {
         if (CreditCardUtil._isCardVisaElectron(cardNumber)) {