VIA-630 Move age calculation from getSession to updateToken on login

Placing the age calculation on getSession had the unintended side
effect of being re-evaluated every time NextAuth loaded the session
(which it does often; twice every minute), and any errors with
the dateOfBirth resulted in a single user outputing many errors in the
logs.

Instead move the age calculation to the point when a user logs in and
user details are being persisted to the token; store age group on the
token for use by the session.

Author: donna-belsey-nhs

src/app/_components/hub/AgeBasedHubCards.tsx

@@ -10,6 +10,9 @@ type AgeBasedHubProps = {
 const AgeBasedHubCards = ({ ageGroup }: AgeBasedHubProps): JSX.Element => {
   const hubInfoForAgeGroup: AgeBasedHubDetails | undefined = AgeBasedHubInfo[ageGroup];
 
+  // TODO VIA-161 Age-Based Hub epic: hubInfo info will be undefined for the age ranges we have not implemented yet
+  //  This is expected for now; fail gracefully and do not render anything
+  //  This boolean check can likely be removed once all ages are implemented
   if (hubInfoForAgeGroup) {
     return (
       <>

src/app/_components/hub/ageGroupHelper.test.ts

@@ -1,24 +1,57 @@
-import { getAgeGroup } from "@src/app/_components/hub/ageGroupHelper";
+import { getAgeGroup, getAgeGroupOfUser } from "@src/app/_components/hub/ageGroupHelper";
 import { AgeGroup } from "@src/models/ageBasedHub";
+import { calculateAge } from "@src/utils/date";
+
+jest.mock("sanitize-data", () => ({ sanitize: jest.fn() }));
+jest.mock("@src/utils/date", () => ({ calculateAge: jest.fn() }));
 
 describe("Age group helper", () => {
-  const expectedGroupsForEachAge = [
-    { age: 12, expectedAgeGroup: AgeGroup.AGE_12_to_16 },
-    { age: 16, expectedAgeGroup: AgeGroup.AGE_12_to_16 },
-    { age: 17, expectedAgeGroup: AgeGroup.AGE_17_to_24 },
-    { age: 24, expectedAgeGroup: AgeGroup.AGE_17_to_24 },
-    { age: 25, expectedAgeGroup: AgeGroup.AGE_25_to_64 },
-    { age: 64, expectedAgeGroup: AgeGroup.AGE_25_to_64 },
-    { age: 65, expectedAgeGroup: AgeGroup.AGE_65_to_74 },
-    { age: 74, expectedAgeGroup: AgeGroup.AGE_65_to_74 },
-    { age: 75, expectedAgeGroup: AgeGroup.AGE_75_to_80 },
-  ];
-
-  it.each(expectedGroupsForEachAge)(`returns $expectedAgeGroup for user age $age`, ({ age, expectedAgeGroup }) => {
-    expect(getAgeGroup(age)).toEqual(expectedAgeGroup);
+  describe("getAgeGroup", () => {
+    const expectedGroupsForEachAge = [
+      { age: 12, expectedAgeGroup: AgeGroup.AGE_12_to_16 },
+      { age: 16, expectedAgeGroup: AgeGroup.AGE_12_to_16 },
+      { age: 17, expectedAgeGroup: AgeGroup.AGE_17_to_24 },
+      { age: 24, expectedAgeGroup: AgeGroup.AGE_17_to_24 },
+      { age: 25, expectedAgeGroup: AgeGroup.AGE_25_to_64 },
+      { age: 64, expectedAgeGroup: AgeGroup.AGE_25_to_64 },
+      { age: 65, expectedAgeGroup: AgeGroup.AGE_65_to_74 },
+      { age: 74, expectedAgeGroup: AgeGroup.AGE_65_to_74 },
+      { age: 75, expectedAgeGroup: AgeGroup.AGE_75_to_80 },
+    ];
+
+    it.each(expectedGroupsForEachAge)(`returns $expectedAgeGroup for user age $age`, ({ age, expectedAgeGroup }) => {
+      expect(getAgeGroup(age)).toEqual(expectedAgeGroup);
+    });
+
+    it("returns unknown age group when age not in defined ranges", () => {
+      expect(getAgeGroup(6)).toBe(AgeGroup.UNKNOWN_AGE_GROUP);
+    });
   });
 
-  it("returns unknown age group when age not in defined ranges", () => {
-    expect(getAgeGroup(6)).toBe(AgeGroup.UNKNOWN_AGE_GROUP);
+  describe("getAgeGroupForUser", () => {
+    const mockDateOfBirth = "mock-dob";
+    const mockCalculatedAge = 30;
+
+    beforeEach(() => {
+      (calculateAge as jest.Mock).mockImplementation(() => mockCalculatedAge);
+    });
+
+    it("should return age group for given dob", () => {
+      const ageGroupForUser = getAgeGroupOfUser(mockDateOfBirth);
+
+      expect(ageGroupForUser).toBe(AgeGroup.AGE_25_to_64);
+    });
+
+    it("should return unknown age group if calculateAge throws", () => {
+      const calculateAgeError = new Error('[{ "code": "custom","message": "Invalid date value","path": []}]');
+
+      (calculateAge as jest.Mock).mockImplementation(() => {
+        throw calculateAgeError;
+      });
+
+      const ageGroupForUser = getAgeGroupOfUser(mockDateOfBirth);
+
+      expect(ageGroupForUser).toBe(AgeGroup.UNKNOWN_AGE_GROUP);
+    });
   });
 });

src/app/_components/hub/ageGroupHelper.ts

@@ -1,4 +1,11 @@
 import { AgeGroup } from "@src/models/ageBasedHub";
+import { calculateAge } from "@src/utils/date";
+import { logger } from "@src/utils/logger";
+import { Logger } from "pino";
+
+const log: Logger = logger.child({
+  module: "age-group-helper",
+});
 
 const getAgeGroup = (age: number): AgeGroup => {
   if (12 <= age && age <= 16) {
@@ -21,4 +28,22 @@ const getAgeGroup = (age: number): AgeGroup => {
   } else return AgeGroup.UNKNOWN_AGE_GROUP;
 };
 
-export { getAgeGroup };
+const getAgeGroupOfUser = (dateOfBirth: string): AgeGroup => {
+  let ageGroupOfUser;
+
+  try {
+    const age = calculateAge(dateOfBirth);
+    ageGroupOfUser = getAgeGroup(age);
+  } catch (error) {
+    ageGroupOfUser = AgeGroup.UNKNOWN_AGE_GROUP;
+    const errorMessage = error instanceof Error && error?.message != undefined ? error.message : "unknown error";
+    const errorCause = error instanceof Error ? error.cause : "";
+    log.error(
+      { error: { message: errorMessage, cause: errorCause } },
+      "User data error; unable to determine age of user",
+    );
+  }
+  return ageGroupOfUser;
+};
+
+export { getAgeGroup, getAgeGroupOfUser };

src/utils/auth/callbacks/get-token.test.ts

@@ -1,3 +1,4 @@
+import { AgeGroup } from "@src/models/ageBasedHub";
 import { ApimHttpError } from "@src/utils/auth/apim/exceptions";
 import { getOrRefreshApimCredentials } from "@src/utils/auth/apim/get-or-refresh-apim-credentials";
 import { getToken } from "@src/utils/auth/callbacks/get-token";
@@ -52,6 +53,7 @@ describe("getToken", () => {
     nhs_number: "test_nhs_number",
     birthdate: "1994-08-04",
   };
+  const expectedAgeGroupForBirthdate = AgeGroup.AGE_25_to_64;
 
   const account = {
     expires_at: nowInSeconds + 1000,
@@ -103,6 +105,7 @@ describe("getToken", () => {
         result,
         profile.nhs_number,
         profile.birthdate,
+        expectedAgeGroupForBirthdate,
         "newIdToken",
         "new-apim-access-token",
         nowInSeconds + 1111,
@@ -119,7 +122,7 @@ describe("getToken", () => {
 
       const result = await getToken(undefinedToken, undefinedAccount, undefinedProfile, maxAgeInSeconds);
 
-      expectResultToMatchTokenWith(result, "", "", "", "", 0, maxAgeInSeconds);
+      expectResultToMatchTokenWith(result, "", "", AgeGroup.UNKNOWN_AGE_GROUP, "", "", 0, maxAgeInSeconds);
     });
 
     it("should fill in missing values in token with default empty string", async () => {
@@ -137,6 +140,7 @@ describe("getToken", () => {
         user: {
           nhs_number: "",
           birthdate: "",
+          age_group: AgeGroup.UNKNOWN_AGE_GROUP,
         },
         nhs_login: {
           id_token: "",
@@ -168,7 +172,16 @@ describe("getToken", () => {
 
       const result = await getToken(token, account, profile, maxAgeInSeconds);
 
-      expectResultToMatchTokenWith(result, profile.nhs_number, profile.birthdate, "newIdToken", "", 0, maxAgeInSeconds);
+      expectResultToMatchTokenWith(
+        result,
+        profile.nhs_number,
+        profile.birthdate,
+        expectedAgeGroupForBirthdate,
+        "newIdToken",
+        "",
+        0,
+        maxAgeInSeconds,
+      );
     });
   });
 
@@ -184,14 +197,24 @@ describe("getToken", () => {
 
       const result = await getToken(token, account, profile, maxAgeInSeconds);
 
-      expectResultToMatchTokenWith(result, profile.nhs_number, profile.birthdate, "newIdToken", "", 0, maxAgeInSeconds);
+      expectResultToMatchTokenWith(
+        result,
+        profile.nhs_number,
+        profile.birthdate,
+        expectedAgeGroupForBirthdate,
+        "newIdToken",
+        "",
+        0,
+        maxAgeInSeconds,
+      );
     });
   });
 
   const expectResultToMatchTokenWith = (
     result: JWT | null,
     nhsNumber: string,
     birthdate: string | null | undefined,
+    ageGroup: AgeGroup,
     idToken: string,
     apimToken: string,
     apimExpiresAt: number,
@@ -202,6 +225,7 @@ describe("getToken", () => {
       user: {
         nhs_number: nhsNumber,
         birthdate: birthdate,
+        age_group: ageGroup,
       },
       nhs_login: {
         id_token: idToken,

src/utils/auth/callbacks/get-token.ts

@@ -1,3 +1,5 @@
+import { getAgeGroupOfUser } from "@src/app/_components/hub/ageGroupHelper";
+import { AgeGroup } from "@src/models/ageBasedHub";
 import { NhsNumber } from "@src/models/vaccine";
 import { getOrRefreshApimCredentials } from "@src/utils/auth/apim/get-or-refresh-apim-credentials";
 import { ApimAccessCredentials } from "@src/utils/auth/apim/types";
@@ -88,6 +90,7 @@ const fillMissingFieldsInTokenWithDefaultValues = (token: JWT, apimAccessCredent
     user: {
       nhs_number: token.user?.nhs_number ?? ("" as NhsNumber),
       birthdate: token.user?.birthdate ?? ("" as BirthDate),
+      age_group: token.user?.age_group ?? AgeGroup.UNKNOWN_AGE_GROUP,
     },
     nhs_login: {
       id_token: token.nhs_login?.id_token ?? ("" as IdToken),
@@ -110,11 +113,14 @@ const updateTokenWithValuesFromAccountAndProfile = (
   nowInSeconds: NowInSeconds,
   maxAgeInSeconds: MaxAgeInSeconds,
 ): JWT => {
+  const ageGroupOfUser = getAgeGroupOfUser(profile.birthdate ?? "");
+
   const updatedToken: JWT = {
     ...token,
     user: {
       nhs_number: (profile.nhs_number ?? "") as NhsNumber,
       birthdate: (profile.birthdate ?? "") as BirthDate,
+      age_group: ageGroupOfUser,
     },
     nhs_login: {
       id_token: (account.id_token ?? "") as IdToken,

src/utils/auth/callbacks/get-updated-session.test.ts

@@ -1,49 +1,42 @@
-import { getAgeGroup } from "@src/app/_components/hub/ageGroupHelper";
 import { AgeGroup } from "@src/models/ageBasedHub";
 import { NhsNumber } from "@src/models/vaccine";
 import { getUpdatedSession } from "@src/utils/auth/callbacks/get-updated-session";
 import { AccessToken, BirthDate, ExpiresAt, IdToken } from "@src/utils/auth/types";
-import { calculateAge } from "@src/utils/date";
 import { Session } from "next-auth";
 import { JWT } from "next-auth/jwt";
 
 jest.mock("sanitize-data", () => ({ sanitize: jest.fn() }));
-jest.mock("@src/utils/date", () => ({ calculateAge: jest.fn() }));
-jest.mock("@src/app/_components/hub/ageGroupHelper.ts", () => ({ getAgeGroup: jest.fn() }));
 
 const mockBirthdate = "1995-01-01";
-const mockCalculatedAge = 30;
-const mockAgeGroup = AgeGroup.AGE_75_to_80;
+const mockAgeGroup = AgeGroup.AGE_17_to_24;
 
-describe("getUpdatedSession", () => {
-  beforeEach(() => {
-    (calculateAge as jest.Mock).mockImplementation(() => mockCalculatedAge);
-    (getAgeGroup as jest.Mock).mockImplementation(() => mockAgeGroup);
-  });
+const session: Session = {
+  user: {
+    nhs_number: "" as NhsNumber,
+    age_group: undefined,
+  },
+  expires: "some-date",
+};
 
-  it("updates session with user fields and age information from token", () => {
-    const session: Session = {
-      user: {
-        nhs_number: "" as NhsNumber,
-        age_group: undefined,
-      },
-      expires: "some-date",
-    };
+const token = {
+  user: {
+    nhs_number: "test-nhs-number" as NhsNumber,
+    birthdate: mockBirthdate as BirthDate,
+    age_group: mockAgeGroup,
+  },
+  nhs_login: {
+    id_token: "test-id-token" as IdToken,
+  },
+  apim: {
+    access_token: "test-access-token" as AccessToken,
+    expires_at: 0 as ExpiresAt,
+  },
+} as JWT;
 
-    const token = {
-      user: {
-        nhs_number: "test-nhs-number" as NhsNumber,
-        birthdate: mockBirthdate as BirthDate,
-      },
-      nhs_login: {
-        id_token: "test-id-token" as IdToken,
-      },
-      apim: {
-        access_token: "test-access-token" as AccessToken,
-        expires_at: 0 as ExpiresAt,
-      },
-    } as JWT;
+describe("getUpdatedSession", () => {
+  beforeEach(() => {});
 
+  it("updates session with user fields and age information from token", () => {
     const result: Session = getUpdatedSession(session, token);
 
     expect(result.user.nhs_number).toBe("test-nhs-number");
@@ -59,16 +52,16 @@ describe("getUpdatedSession", () => {
       expires: "some-date",
     };
 
-    const token = {} as JWT;
+    const emptyToken = {} as JWT;
 
-    const result: Session = getUpdatedSession(session, token);
+    const result: Session = getUpdatedSession(session, emptyToken);
 
     expect(result.user.nhs_number).toBe("old-nhs-number");
     expect(result.user.age_group).toBe(AgeGroup.AGE_25_to_64);
   });
 
   it("does not update session if session.user is missing", () => {
-    const session = {
+    const sessionWithoutUser = {
       expires: "some-date",
     } as Session;
 
@@ -79,7 +72,7 @@ describe("getUpdatedSession", () => {
       },
     } as JWT;
 
-    const result: Session = getUpdatedSession(session, token);
+    const result: Session = getUpdatedSession(sessionWithoutUser, token);
 
     expect(result.user).toBeUndefined();
   });

src/utils/auth/callbacks/get-updated-session.ts

@@ -1,5 +1,3 @@
-import { getAgeGroup } from "@src/app/_components/hub/ageGroupHelper";
-import { calculateAge } from "@src/utils/date";
 import { logger } from "@src/utils/logger";
 import { Session } from "next-auth";
 import { JWT } from "next-auth/jwt";
@@ -12,7 +10,7 @@ const log: Logger = logger.child({
 const getUpdatedSession = (session: Session, token: JWT): Session => {
   if (token?.user && session.user) {
     session.user.nhs_number = token.user.nhs_number;
-    session.user.age_group = getAgeGroup(calculateAge(token.user.birthdate));
+    session.user.age_group = token.user.age_group;
   } else {
     log.info(
       {

src/utils/auth/types.d.ts

@@ -61,6 +61,7 @@ declare module "next-auth/jwt" {
     user: {
       nhs_number: NhsNumber;
       birthdate: BirthDate;
+      age_group: AgeGroup;
     };
     nhs_login: {
       id_token: IdToken;