Chore: [AEA-5824] - avoid undefined supplier status (#2268)

## Summary

- Routine Change

### Details

Avoid writing supplierStatus as `undefined` by initialising and checking
for out of sequence Notify msgs

Author: tstephen-nhs

packages/nhsNotifyLambda/jest.config.ts

@@ -1,17 +1,10 @@
-import defaultConfig from "../../jest.default.config"
 import type {JestConfigWithTsJest} from "ts-jest"
+import defaultConfig from "../../jest.default.config"
 
 const jestConfig: JestConfigWithTsJest = {
   ...defaultConfig,
   rootDir: "./",
-  setupFiles: ["<rootDir>/.jest/setEnvVars.js"],
-  coveragePathIgnorePatterns: ["<rootDir>/tests/"],
-  coverageReporters: [
-    "clover",
-    "json",
-    "text",
-    ["lcov", {projectRoot: "../../"}]
-  ]
+  setupFiles: ["<rootDir>/.jest/setEnvVars.js"]
 }
 
 export default jestConfig

packages/nhsNotifyLambda/src/utils/dynamo.ts

@@ -38,6 +38,7 @@ export async function addPrescriptionMessagesToNotificationStateStore(
       SQSMessageID: data.MessageId,
       LastNotifiedPrescriptionStatus: data.PSUDataItem.Status,
       MessageStatus: data.messageStatus ?? "unknown", // Fall back to unknown if not set
+      SupplierStatus: "unknown", // set explicitly so can distinguish callback values
       NotifyMessageID: data.notifyMessageId, // This is a GSI, but leaving it blank is fine
       NotifyMessageReference: data.messageReference,
       NotifyMessageBatchReference: data.messageBatchReference, // Will be undefined when request fails

packages/nhsNotifyUpdateCallback/jest.config.ts

@@ -4,14 +4,7 @@ import type {JestConfigWithTsJest} from "ts-jest"
 const jestConfig: JestConfigWithTsJest = {
   ...defaultConfig,
   rootDir: "./",
-  setupFiles: ["<rootDir>/.jest/setEnvVars.js"],
-  coveragePathIgnorePatterns: ["<rootDir>/tests/"],
-  coverageReporters: [
-    "clover",
-    "json",
-    "text",
-    ["lcov", {projectRoot: "../../"}]
-  ]
+  setupFiles: ["<rootDir>/.jest/setEnvVars.js"]
 }
 
 export default jestConfig

packages/nhsNotifyUpdateCallback/src/helpers.ts

@@ -133,7 +133,6 @@ export function extractStatusesAndDescriptions(logger: Logger, resource: Callbac
     messageStatus = resource.attributes.messageStatus
     messageStatusDescription = resource.attributes.messageStatusDescription
     channelStatus = resource.attributes.channels?.[0]?.channelStatus // If missing, undefined
-    supplierStatus = undefined
   } else if (resource.type === CallbackType.channel) {
     messageStatus = undefined
     retryCount = resource.attributes.retryCount
@@ -247,10 +246,10 @@ export async function updateNotificationsTable(
       // But we don't have enough information to do that so we ignore that edge case and
       // count it as a success.
     }
+    const upToDateItems = filterOutOfDateItems(logger, resource, items)
 
     const newExpiry = Math.floor(Date.now() / 1000) + TTL_DELTA
-
-    const updatePromises = items.map(async item => {
+    const updatePromises = upToDateItems.map(async item => {
       const key = {
         NHSNumber: item.NHSNumber,
         RequestId: item.RequestId
@@ -315,3 +314,31 @@ export async function updateNotificationsTable(
 
   await Promise.all(callbackPromises)
 }
+
+function filterOutOfDateItems(
+  logger: Logger,
+  resource: CallbackResource,
+  items: Array<LastNotificationStateType>
+) {
+  const upToDateItems = items.filter(item => {
+    const isOld = item.LastNotificationRequestTimestamp &&
+      item.LastNotificationRequestTimestamp > resource.attributes.timestamp
+    if (isOld) {
+      logger.warn(
+        "Ignoring out-of-date callback",
+        {
+          messageId: resource.attributes.messageId,
+          messageReference: resource.attributes.messageReference,
+          lastTimestamp: item.LastNotificationRequestTimestamp,
+          currentTimestamp: resource.attributes.timestamp
+        }
+      )
+    }
+    return !isOld
+  })
+  logger.info(
+    "Number of up-to-date items remaining",
+    {count: upToDateItems.length}
+  )
+  return upToDateItems
+}

packages/nhsNotifyUpdateCallback/tests/testHelpers.test.ts

@@ -165,6 +165,41 @@ describe("helpers.ts", () => {
       )
     })
 
+    it("skips update when callback is out of date", async () => {
+      const msgTimestamp = "2025-01-01T00:00:00.000Z"
+      const lastTimestamp = "2025-02-01T00:00:00.000Z" // newer than msg payload
+      const msgPayload: MessageStatusResponse = generateMockMessageStatusResponse([
+        {
+          attributes: {
+            timestamp: msgTimestamp
+          }
+        }])
+      const mockItem = {
+        NHSNumber: "NHS123",
+        RequestId: "psu-request-id",
+        NotifyMessageID: "msg-123",
+        LastNotificationRequestTimestamp: lastTimestamp
+      }
+      sendSpy.mockImplementation((cmd) => {
+        if (cmd instanceof QueryCommand) {
+          return Promise.resolve({Items: [mockItem]})
+        }
+      })
+
+      await updateNotificationsTable(logger, msgPayload)
+
+      expect(logger.warn).toHaveBeenCalledWith(
+        "Ignoring out-of-date callback",
+        expect.objectContaining({messageId: msgPayload.data[0].attributes.messageId})
+      )
+      expect(logger.info).toHaveBeenCalledWith(
+        "Number of up-to-date items remaining",
+        expect.objectContaining({count: 0})
+      )
+      // Only QueryCommand should be called
+      expect(sendSpy).toHaveBeenCalledTimes(1)
+    })
+
     it("updates records when matching items found (Message update callback)", async () => {
       const overrideTimestamp = "2025-01-01T00:00:00.000Z"
       const mockResponse = generateMockMessageStatusResponse([
@@ -180,7 +215,8 @@ describe("helpers.ts", () => {
       const mockItem = {
         NHSNumber: "NHS123",
         RequestId: "psu-request-id",
-        NotifyMessageID: "msg-123"
+        NotifyMessageID: "msg-123",
+        LastNotificationRequestTimestamp: "2024-01-01T00:00:00.000Z" // old timestamp
       }
 
       // First call: QueryCommand