feat(web): streamline login for returning users

packages/backend/src/auth/controllers/auth.controller.ts

@@ -116,7 +116,9 @@ class AuthController {
           : await this.signup(gUser, gRefreshToken);
 
       const sUserId = supertokens.convertToRecipeUserId(cUserId);
-      await Session.createNewSession(req, res, "public", sUserId);
+      await Session.createNewSession(req, res, "public", sUserId, {
+        email,
+      });
 
       const result: Result_Auth_Compass = {
         cUserId,

packages/backend/src/common/types/supertokens.types.ts

@@ -9,4 +9,5 @@ export interface SupertokensAccessTokenPayload {
   parentRefreshTokenHash1: string | null;
   antiCsrfToken: string | null;
   iss: string;
+  email?: string;
 }

packages/web/src/auth/ProtectedRoute.tsx

@@ -1,4 +1,4 @@
-import React, { ReactNode, useEffect } from "react";
+import { ReactNode, useEffect } from "react";
 import { useNavigate } from "react-router-dom";
 import { AUTH_FAILURE_REASONS } from "@web/common/constants/auth.constants";
 import { ROOT_ROUTES } from "@web/common/constants/routes";

packages/web/src/auth/UserProvider.test.tsx

@@ -0,0 +1,246 @@
+import { usePostHog } from "posthog-js/react";
+import Session from "supertokens-auth-react/recipe/session";
+import "@testing-library/jest-dom";
+import { render, waitFor } from "@testing-library/react";
+import { UserProvider } from "./UserProvider";
+
+// Mock PostHog
+jest.mock("posthog-js/react");
+const mockUsePostHog = usePostHog as jest.MockedFunction<typeof usePostHog>;
+
+// Mock SuperTokens Session
+jest.mock("supertokens-auth-react/recipe/session");
+const mockSession = Session as jest.Mocked<typeof Session>;
+
+// Mock AbsoluteOverflowLoader
+jest.mock("@web/components/AbsoluteOverflowLoader", () => ({
+  AbsoluteOverflowLoader: () => <div>Loading...</div>,
+}));
+
+describe("UserProvider", () => {
+  const mockIdentify = jest.fn();
+  const mockGetAccessTokenPayloadSecurely = jest.fn();
+
+  beforeEach(() => {
+    jest.clearAllMocks();
+
+    // Default mock implementation
+    mockSession.getAccessTokenPayloadSecurely =
+      mockGetAccessTokenPayloadSecurely;
+  });
+
+  describe("PostHog Integration", () => {
+    it("should call posthog.identify when PostHog is enabled and user data is available", async () => {
+      const testUserId = "test-user-123";
+      const testEmail = "test@example.com";
+
+      // Mock session with userId and email
+      mockGetAccessTokenPayloadSecurely.mockResolvedValue({
+        sub: testUserId,
+        email: testEmail,
+      });
+
+      // Mock PostHog as enabled
+      mockUsePostHog.mockReturnValue({
+        identify: mockIdentify,
+      } as any);
+
+      render(
+        <UserProvider>
+          <div>Test Child</div>
+        </UserProvider>,
+      );
+
+      // Wait for async data fetch and PostHog identify to be called
+      await waitFor(() => {
+        expect(mockIdentify).toHaveBeenCalledWith(testEmail, {
+          email: testEmail,
+          userId: testUserId,
+        });
+      });
+
+      // Verify it was called exactly once
+      expect(mockIdentify).toHaveBeenCalledTimes(1);
+    });
+
+    it("should NOT call posthog.identify when PostHog is disabled", async () => {
+      const testUserId = "test-user-123";
+      const testEmail = "test@example.com";
+
+      // Mock session with userId and email
+      mockGetAccessTokenPayloadSecurely.mockResolvedValue({
+        sub: testUserId,
+        email: testEmail,
+      });
+
+      // Mock PostHog as disabled (returns undefined/null)
+      mockUsePostHog.mockReturnValue(undefined as any);
+
+      render(
+        <UserProvider>
+          <div>Test Child</div>
+        </UserProvider>,
+      );
+
+      // Wait a bit to ensure no identify call happens
+      await waitFor(() => {
+        expect(mockGetAccessTokenPayloadSecurely).toHaveBeenCalled();
+      });
+
+      // Verify identify was never called
+      expect(mockIdentify).not.toHaveBeenCalled();
+    });
+
+    it("should NOT call posthog.identify when email is missing from session", async () => {
+      const testUserId = "test-user-123";
+
+      // Mock session with userId but NO email
+      mockGetAccessTokenPayloadSecurely.mockResolvedValue({
+        sub: testUserId,
+        // email is missing
+      });
+
+      // Mock PostHog as enabled
+      mockUsePostHog.mockReturnValue({
+        identify: mockIdentify,
+      } as any);
+
+      render(
+        <UserProvider>
+          <div>Test Child</div>
+        </UserProvider>,
+      );
+
+      // Wait for data fetch
+      await waitFor(() => {
+        expect(mockGetAccessTokenPayloadSecurely).toHaveBeenCalled();
+      });
+
+      // Verify identify was not called because email is missing
+      expect(mockIdentify).not.toHaveBeenCalled();
+    });
+
+    it("should NOT call posthog.identify when userId is missing", async () => {
+      const testEmail = "test@example.com";
+
+      // Mock session with email but NO userId (sub)
+      mockGetAccessTokenPayloadSecurely.mockResolvedValue({
+        email: testEmail,
+        // sub is missing
+      });
+
+      // Mock PostHog as enabled
+      mockUsePostHog.mockReturnValue({
+        identify: mockIdentify,
+      } as any);
+
+      render(
+        <UserProvider>
+          <div>Test Child</div>
+        </UserProvider>,
+      );
+
+      // The component should show loading state because userId is null
+      // and identify should never be called
+      await waitFor(() => {
+        expect(mockGetAccessTokenPayloadSecurely).toHaveBeenCalled();
+      });
+
+      expect(mockIdentify).not.toHaveBeenCalled();
+    });
+
+    it("should handle posthog.identify not being a function gracefully", async () => {
+      const testUserId = "test-user-123";
+      const testEmail = "test@example.com";
+
+      // Mock session with userId and email
+      mockGetAccessTokenPayloadSecurely.mockResolvedValue({
+        sub: testUserId,
+        email: testEmail,
+      });
+
+      // Mock PostHog with identify not being a function
+      mockUsePostHog.mockReturnValue({
+        identify: null,
+      } as any);
+
+      // Should not throw an error
+      expect(() => {
+        render(
+          <UserProvider>
+            <div>Test Child</div>
+          </UserProvider>,
+        );
+      }).not.toThrow();
+
+      await waitFor(() => {
+        expect(mockGetAccessTokenPayloadSecurely).toHaveBeenCalled();
+      });
+
+      // Verify identify was not called
+      expect(mockIdentify).not.toHaveBeenCalled();
+    });
+
+    it("should render children after user data is loaded", async () => {
+      const testUserId = "test-user-123";
+      const testEmail = "test@example.com";
+
+      mockGetAccessTokenPayloadSecurely.mockResolvedValue({
+        sub: testUserId,
+        email: testEmail,
+      });
+
+      mockUsePostHog.mockReturnValue({
+        identify: mockIdentify,
+      } as any);
+
+      const { getByText } = render(
+        <UserProvider>
+          <div>Test Child Content</div>
+        </UserProvider>,
+      );
+
+      // Initially should show loading
+      expect(getByText("Loading...")).toBeInTheDocument();
+
+      // After data loads, should show children
+      await waitFor(() => {
+        expect(getByText("Test Child Content")).toBeInTheDocument();
+      });
+    });
+
+    it("should handle session fetch errors gracefully", async () => {
+      const consoleErrorSpy = jest
+        .spyOn(console, "error")
+        .mockImplementation(() => {});
+
+      // Mock session to throw an error
+      mockGetAccessTokenPayloadSecurely.mockRejectedValue(
+        new Error("Session error"),
+      );
+
+      mockUsePostHog.mockReturnValue({
+        identify: mockIdentify,
+      } as any);
+
+      render(
+        <UserProvider>
+          <div>Test Child</div>
+        </UserProvider>,
+      );
+
+      // Should log error
+      await waitFor(() => {
+        expect(consoleErrorSpy).toHaveBeenCalledWith(
+          "Failed to get user because:",
+          expect.any(Error),
+        );
+      });
+
+      // Should not call identify
+      expect(mockIdentify).not.toHaveBeenCalled();
+
+      consoleErrorSpy.mockRestore();
+    });
+  });
+});

packages/web/src/auth/UserContext.tsx → packages/web/src/auth/UserProvider.tsx

@@ -1,36 +1,49 @@
-import React, {
+import { usePostHog } from "posthog-js/react";
+import {
   ReactNode,
   createContext,
-  useContext,
+  useEffect,
   useLayoutEffect,
   useState,
 } from "react";
 import { AbsoluteOverflowLoader } from "@web/components/AbsoluteOverflowLoader";
-import { getUserId } from "./auth.util";
+import { getUserEmail, getUserId } from "./auth.util";
 
 const UserContext = createContext<
   { isLoadingUser: boolean; userId: string } | undefined
 >(undefined);
 
 export const UserProvider = ({ children }: { children: ReactNode }) => {
   const [userId, setUserId] = useState<string | null>(null);
+  const [email, setEmail] = useState<string | null>(null);
   const [isLoadingUser, setIsLoadingUser] = useState(false);
+  const posthog = usePostHog();
 
   useLayoutEffect(() => {
-    const fetchUserId = async () => {
+    const fetchUserData = async () => {
       try {
         const uid = await getUserId();
+        const userEmail = await getUserEmail();
         setUserId(uid);
+        setEmail(userEmail);
       } catch (e) {
         console.error("Failed to get user because:", e);
       } finally {
         setIsLoadingUser(false);
       }
     };
 
-    void fetchUserId();
+    void fetchUserData();
   }, []);
 
+  // Identify user in PostHog when userId and email are available
+  // Only runs if PostHog is enabled (POSTHOG_HOST and POSTHOG_KEY are set)
+  useEffect(() => {
+    if (userId && email && posthog && typeof posthog.identify === "function") {
+      posthog.identify(email, { email, userId });
+    }
+  }, [userId, email, posthog]);
+
   if (isLoadingUser || userId === null) {
     return <AbsoluteOverflowLoader />;
   }
@@ -41,13 +54,3 @@ export const UserProvider = ({ children }: { children: ReactNode }) => {
     </UserContext.Provider>
   );
 };
-
-export const useUser = () => {
-  const context = useContext(UserContext);
-
-  if (context === undefined) {
-    throw new Error("useUser must be used within a UserProvider");
-  }
-
-  return context;
-};

packages/web/src/auth/auth.util.ts

@@ -2,6 +2,7 @@ import Session from "supertokens-auth-react/recipe/session";
 
 interface AccessTokenPayload {
   sub: string;
+  email?: string;
 }
 
 export const getUserId = async () => {
@@ -10,3 +11,17 @@ export const getUserId = async () => {
   const userId = accessTokenPayload["sub"];
   return userId;
 };
+
+/**
+ * Get the user's email from the session access token payload
+ */
+export const getUserEmail = async (): Promise<string | null> => {
+  try {
+    const accessTokenPayload =
+      (await Session.getAccessTokenPayloadSecurely()) as AccessTokenPayload;
+    return accessTokenPayload.email || null;
+  } catch (error) {
+    console.error("Failed to get user email:", error);
+    return null;
+  }
+};