feat(#9227): add validation function for luhn algorithm

Co-authored-by: Anro Swart <[email protected]>
medic · Jul 15, 2024 · 3c2b140 · 3c2b140
1 parent 1e9efb7
commit 3c2b140
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Showing 2 changed files with 136 additions and 2 deletions.
diff --git a/webapp/src/js/enketo/medic-xpath-extensions.js b/webapp/src/js/enketo/medic-xpath-extensions.js
@@ -4,6 +4,7 @@ const XPR = {
   number: v => ({ t: 'num', v }),
   string: v => ({ t: 'str', v }),
   date: v => ({ t: 'date', v }),
+  bool: v => ({ t: 'bool', v}),
 };
 const MOMENT_KEYS = {
   YEARS: 'years',
@@ -162,6 +163,37 @@ const dateDiff = function (startDateObj, endDateObj, key) {
   return XPR.number(endDate.diff(startDate, key));
 };
 
+const stripWhitespace = function (string) {
+  return XPR.string(stripSpace(string));
+};
+
+const stripSpace = (s) => getValue(s).toString().trim().replace(/\s/g, '');
+
+const luhn = function (number, expLength) {
+  number = stripSpace(number);
+
+  if (!/^\d+$/.test(number) || (expLength && number.length !== expLength)) {
+    return XPR.bool(false);
+  }
+
+  const digits = number.split('').map(Number);
+  let sum = 0;
+  let isSecond = false;
+  for (let i = digits.length - 1; i >= 0; i--) {
+    let digit = digits[i];
+    if (isSecond) {
+      digit *= 2;
+      if (digit > 9) {
+        digit -= 9;
+      }
+    }
+    sum += digit;
+    isSecond = !isSecond;
+  }
+
+  return XPR.bool(sum % 10 === 0);
+};
+
 module.exports = {
   getTimezoneOffsetAsTime: getTimezoneOffsetAsTime,
   toISOLocalString: toISOLocalString,
@@ -190,6 +222,8 @@ module.exports = {
     'difference-in-months': (d1, d2) => dateDiff(d1, d2, MOMENT_KEYS.MONTHS), // To be deprecated
     'cht:difference-in-weeks': (d1, d2) => dateDiff(d1, d2, MOMENT_KEYS.WEEKS),
     'cht:difference-in-days': (d1, d2) => dateDiff(d1, d2, MOMENT_KEYS.DAYS),
+    'cht:strip-whitespace': stripWhitespace,
+    'cht:validate-luhn': luhn,
     'cht:extension-lib': function () {
       const args = Array.from(arguments);
       const firstArg = args.shift();

diff --git a/webapp/tests/mocha/unit/enketo/medic-xpath-extensions.spec.js b/webapp/tests/mocha/unit/enketo/medic-xpath-extensions.spec.js
@@ -7,7 +7,7 @@ medicXpathExtensions.init(null, toBik_text, moment);
 const func = medicXpathExtensions.func;
 
 describe('medic-xpath-extensions', function () {
-  const wrapDate = (date) => { 
+  const wrapDate = (date) => {
     return { t: 'str', v: date };
   };
 
@@ -87,7 +87,7 @@ describe('medic-xpath-extensions', function () {
 
   describe('#difference-in-months', function () {
     const diffInMonths = func['cht:difference-in-months'];
-    
+
     [
       ['2015-10-01', '2015-10-01', 0,],
       ['2015-09-01', '2015-10-01', 1,],
@@ -380,4 +380,104 @@ describe('medic-xpath-extensions', function () {
       });
     });
   });
+
+  describe('#strip-whitespace()', () => {
+    const test = func['cht:strip-whitespace'];
+
+    it('should return a string without any white spaces', () => {
+      const idNumber = { t: 'arr', v: [{ textContent: ' 65 05\n 28  5125 086 ' }] };
+      const result = test(idNumber);
+      assert.strictEqual(/\s/.test(result.v), false);
+    });
+  });
+
+  describe('#validate-luhn()', () => {
+    const test = func['cht:validate-luhn'];
+
+    it('should return true for a valid South African ID number', () => {
+      const idNumber = { t: 'arr', v: [{ textContent: '6505285125086' }] };
+      const result = test(idNumber, 13);
+      assert.strictEqual(result.v, true);
+    });
+    it('should return false for an South African ID number that does not contain 13 digits', () => {
+      const idNumber = { t: 'arr', v: [{ textContent: '650528512508' }] };
+      const result = test(idNumber, 13);
+      assert.strictEqual(result.v, false);
+    });
+    it('should return false for an invalid South African ID number ', () => {
+      const idNumber = { t: 'arr', v: [{ textContent: '6505285125085' }] };
+      const result = test(idNumber, 13);
+      assert.strictEqual(result.v, false);
+    });
+    it('should return false for a non-numeric South African ID number', () => {
+      const idNumber = { t: 'arr', v: [{ textContent: '650528512a086' }] };
+      const result = test(idNumber, 13);
+      assert.strictEqual(result.v, false);
+    });
+    it('should return true for a valid South African ID number with spaces', () => {
+      const idNumber = { t: 'arr', v: [{ textContent: '6505  2851  2508 6' }] };
+      const result = test(idNumber, 13);
+      assert.strictEqual(result.v, true);
+    });
+    it('should return true for a valid South African ID number with leading/trailing spaces', () => {
+      const idNumber = { t: 'arr', v: [{ textContent: '  6505285125086  ' }] };
+      const result = test(idNumber, 13);
+      assert.strictEqual(result.v, true);
+    });
+
+    it('should return true for a valid American Express credit card number', () => {
+      const idNumber = { t: 'arr', v: [{ textContent: '371449635398431' }] };
+      const result = test(idNumber, 15);
+      assert.strictEqual(result.v, true);
+    });
+    it('should return false for an invalid American Express credit card number', () => {
+      const idNumber = { t: 'arr', v: [{ textContent: '371449635398432' }] };
+      const result = test(idNumber, 15);
+      assert.strictEqual(result.v, false);
+    });
+
+    it('should return true for a valid Visa credit card number', () => {
+      const idNumber = { t: 'arr', v: [{ textContent: '4532015112830366' }] };
+      const result = test(idNumber, 16);
+      assert.strictEqual(result.v, true);
+    });
+    it('should return false for an invalid Visa credit card number', () => {
+      const idNumber = { t: 'arr', v: [{ textContent: '4532015112830367' }] };
+      const result = test(idNumber, 16);
+      assert.strictEqual(result.v, false);
+    });
+
+    it('should return true for a valid MasterCard credit card number', () => {
+      const idNumber = { t: 'arr', v: [{ textContent: '5555555555554444' }] };
+      const result = test(idNumber, 16);
+      assert.strictEqual(result.v, true);
+    });
+    it('should return false for an invalid MasterCard credit card number', () => {
+      const idNumber = { t: 'arr', v: [{ textContent: '5555555555554445' }] };
+      const result = test(idNumber, 16);
+      assert.strictEqual(result.v, false);
+    });
+
+    it('should return true for a valid Discover credit card number', () => {
+      const idNumber = { t: 'arr', v: [{ textContent: '6011000990139424' }] };
+      const result = test(idNumber, 16);
+      assert.strictEqual(result.v, true);
+    });
+    it('should return false for an invalid Discover credit card number', () => {
+      const idNumber = { t: 'arr', v: [{ textContent: '6011000990139425' }] };
+      const result = test(idNumber, 16);
+      assert.strictEqual(result.v, false);
+    });
+
+    it('should return true for a valid luhn number without specifying a length', () => {
+      const number = { t: 'arr', v: [{ textContent: '6505285125086' }] };
+      const result = test(number);
+      assert.strictEqual(result.v, true);
+    });
+    it('should return false for a invalid luhn number without specifying a length', () => {
+      const number = { t: 'arr', v: [{ textContent: '6011000990139425' }] };
+      const result = test(number);
+      assert.strictEqual(result.v, false);
+    });
+  });
 });