chore: add payments by product backend validation

src/app/modules/payments/__tests__/payments.service.spec.ts

@@ -155,7 +155,147 @@ describe('payments.service', () => {
         InvalidPaymentProductsError,
       )
       expect(result._unsafeUnwrapErr().message).toContain(
-        'Invalid product selected.',
+        'There has been a change in the products available.',
+      )
+    })
+
+    it('should return with error if the description has changed', () => {
+      // Arrange
+      const mockInvalidProductSubmission: ProductItem[] = [
+        {
+          data: {
+            ...mockValidProduct,
+            description: 'some other description',
+            _id: new ObjectId(),
+          } as unknown as Product,
+          quantity: 1,
+          selected: true,
+        },
+        {
+          data: mockValidProduct,
+          quantity: 1,
+          selected: true,
+        },
+      ]
+
+      // Act
+      const result = PaymentsService.validatePaymentProducts(
+        mockValidProductsDefinition,
+        mockInvalidProductSubmission,
+      )
+
+      // Assert
+      expect(result.isErr()).toBeTrue()
+      expect(result._unsafeUnwrapErr()).toBeInstanceOf(
+        InvalidPaymentProductsError,
+      )
+      expect(result._unsafeUnwrapErr().message).toContain(
+        'There has been a change in the products available.',
+      )
+    })
+
+    it('should return with error if the name has changed', () => {
+      // Arrange
+      const mockInvalidProductSubmission: ProductItem[] = [
+        {
+          data: {
+            ...mockValidProduct,
+            name: 'some other name',
+            _id: new ObjectId(),
+          } as unknown as Product,
+          quantity: 1,
+          selected: true,
+        },
+        {
+          data: mockValidProduct,
+          quantity: 1,
+          selected: true,
+        },
+      ]
+
+      // Act
+      const result = PaymentsService.validatePaymentProducts(
+        mockValidProductsDefinition,
+        mockInvalidProductSubmission,
+      )
+
+      // Assert
+      expect(result.isErr()).toBeTrue()
+      expect(result._unsafeUnwrapErr()).toBeInstanceOf(
+        InvalidPaymentProductsError,
+      )
+      expect(result._unsafeUnwrapErr().message).toContain(
+        'There has been a change in the products available.',
+      )
+    })
+
+    it('should return with error if multi_qty has changed', () => {
+      // Arrange
+      const mockInvalidProductSubmission: ProductItem[] = [
+        {
+          data: {
+            ...mockValidProduct,
+            multi_qty: true,
+            _id: new ObjectId(),
+          } as unknown as Product,
+          quantity: 1,
+          selected: true,
+        },
+        {
+          data: mockValidProduct,
+          quantity: 1,
+          selected: true,
+        },
+      ]
+
+      // Act
+      const result = PaymentsService.validatePaymentProducts(
+        mockValidProductsDefinition,
+        mockInvalidProductSubmission,
+      )
+
+      // Assert
+      expect(result.isErr()).toBeTrue()
+      expect(result._unsafeUnwrapErr()).toBeInstanceOf(
+        InvalidPaymentProductsError,
+      )
+      expect(result._unsafeUnwrapErr().message).toContain(
+        'There has been a change in the products available.',
+      )
+    })
+
+    it('should return with error if the max_qty has changed', () => {
+      // Arrange
+      const mockInvalidProductSubmission: ProductItem[] = [
+        {
+          data: {
+            ...mockValidProduct,
+            max_qty: 5,
+            _id: new ObjectId(),
+          } as unknown as Product,
+          quantity: 1,
+          selected: true,
+        },
+        {
+          data: mockValidProduct,
+          quantity: 1,
+          selected: true,
+        },
+      ]
+
+      // Act
+      const result = PaymentsService.validatePaymentProducts(
+        mockValidProductsDefinition,
+        mockInvalidProductSubmission,
+      )
+
+      // Assert
+      expect(result.isErr()).toBeTrue()
+      expect(result._unsafeUnwrapErr()).toBeInstanceOf(
+        InvalidPaymentProductsError,
+      )
+      expect(result._unsafeUnwrapErr().message).toContain(
+        'There has been a change in the products available.',
       )
     })
 
@@ -264,7 +404,7 @@ describe('payments.service', () => {
       )
     })
 
-    it('should return with error if submitted price is not the same as in form defintion', () => {
+    it('should return with error if submitted price is not the same as in form definition', () => {
       // Arrange
       const mockProductWithCorrectPrice = {
         name: 'some name',
@@ -303,7 +443,9 @@ describe('payments.service', () => {
       expect(result._unsafeUnwrapErr()).toBeInstanceOf(
         InvalidPaymentProductsError,
       )
-      expect(result._unsafeUnwrapErr().message).toContain('Price has changed')
+      expect(result._unsafeUnwrapErr().message).toContain(
+        'There has been a change in the products available',
+      )
     })
   })
 

src/app/modules/payments/payments.service.ts

@@ -1,3 +1,4 @@
+import { isEqual } from 'lodash'
 import moment from 'moment-timezone'
 import mongoose, { Types } from 'mongoose'
 import { err, errAsync, ok, okAsync, Result, ResultAsync } from 'neverthrow'
@@ -404,20 +405,20 @@ export const validatePaymentProducts = (
   }
 
   for (const product of submittedPaymentProducts) {
-    // Check that every selected product is in the form definition
+    // Check that every selected product matches the form definition
+
     const productIdSubmitted = product.data._id
     const productDefinition = formProductsDefinition.find(
       (product) => String(product._id) === String(productIdSubmitted),
     )
-
-    if (!productDefinition) {
+    if (!productDefinition || !isEqual(productDefinition, product.data)) {
       logger.error({
         message: 'Invalid payment product selected.',
         meta: logMeta,
       })
       return err(
         new InvalidPaymentProductsError(
-          'Invalid product selected. Please refresh and try again.',
+          'There has been a change in the products available. Please refresh and try again.',
         ),
       )
     }
@@ -464,14 +465,6 @@ export const validatePaymentProducts = (
         )
       }
     }
-
-    if (product.data.amount_cents !== productDefinition.amount_cents) {
-      return err(
-        new InvalidPaymentProductsError(
-          `Price has changed. Please refresh and try again.`,
-        ),
-      )
-    }
   }
 
   return ok(true)