feat: implement notification controller for handling incoming notifications with signature verification and add corresponding unit tests.

tests/unit/notification.controller.test.js

@@ -19,9 +19,8 @@ describe('NotificationController', () => {
         };
     });
 
-    it('should handle notification successfully when token and signature are valid', async () => {
+    it('should handle notification successfully when signature is valid', async () => {
         mockReq = {
-            headers: { 'x-callback-token': routerToken },
             body: { order_id: 'I-123', transaction_status: 'settlement' }
         };
 
@@ -35,20 +34,9 @@ describe('NotificationController', () => {
         expect(responseHelper.success).toHaveBeenCalledWith(mockRes, expect.stringContaining('Handled'));
     });
 
-    it('should return 401 if x-callback-token is invalid', async () => {
-        mockReq = {
-            headers: { 'x-callback-token': 'wrong-token' },
-            body: {}
-        };
-
-        await NotificationController.handle(mockReq, mockRes);
-
-        expect(responseHelper.error).toHaveBeenCalledWith(mockRes, expect.stringContaining('Unauthorized token'), 401);
-    });
 
     it('should return 403 if signature invalid', async () => {
         mockReq = {
-            headers: { 'x-callback-token': routerToken },
             body: { signature_key: 'invalid' }
         };
         notificationService.verifySignature.mockReturnValue(false);
@@ -60,7 +48,6 @@ describe('NotificationController', () => {
 
     it('should return error on service error', async () => {
         mockReq = {
-            headers: { 'x-callback-token': routerToken },
             body: { order_id: 'I-123' }
         };
         notificationService.verifySignature.mockReturnValue(true);