Refactor: Abstract PostHog tracking into analytics helper

- Move server-side PostHog client into lib/analytics/index.ts
- Create 'analytics' object with capture() and identify() methods
- Mirrors the client-side useAnalytics() hook pattern
- Remove separate posthog-server.ts file
- Update invitation acceptance to use analytics.capture()

Co-authored-by: marcftone <marcftone@gmail.com>

lib/analytics/index.ts

@@ -1,9 +1,14 @@
 import { emptyAnalytics, jitsuAnalytics } from "@jitsu/js";
+import { PostHog } from "posthog-node";
 import { posthog } from "posthog-js";
 
 import { getPostHogConfig } from "@/lib/posthog";
 import { AnalyticsEvents } from "@/lib/types";
 
+// =============================================================================
+// Client-side Analytics (PostHog via posthog-js)
+// =============================================================================
+
 export function useAnalytics() {
   const isPostHogEnabled = getPostHogConfig();
 
@@ -38,8 +43,11 @@ export function useAnalytics() {
   };
 }
 
-// For server-side tracking
-const analytics =
+// =============================================================================
+// Server-side Analytics (Jitsu)
+// =============================================================================
+
+const jitsu =
   process.env.JITSU_HOST && process.env.JITSU_WRITE_KEY
     ? jitsuAnalytics({
         host: process.env.JITSU_HOST,
@@ -47,5 +55,95 @@ const analytics =
       })
     : emptyAnalytics;
 
-export const identifyUser = (userId: string) => analytics.identify(userId);
-export const trackAnalytics = (args: AnalyticsEvents) => analytics.track(args);
+export const identifyUser = (userId: string) => jitsu.identify(userId);
+export const trackAnalytics = (args: AnalyticsEvents) => jitsu.track(args);
+
+// =============================================================================
+// Server-side Analytics (PostHog via posthog-node)
+// =============================================================================
+
+let posthogServerClient: PostHog | null = null;
+
+function getPostHogServerClient(): PostHog | null {
+  const postHogKey = process.env.NEXT_PUBLIC_POSTHOG_KEY;
+
+  if (!postHogKey) {
+    return null;
+  }
+
+  if (!posthogServerClient) {
+    posthogServerClient = new PostHog(postHogKey, {
+      host: "https://eu.i.posthog.com",
+      // Flush events immediately in serverless environments
+      flushAt: 1,
+      flushInterval: 0,
+    });
+  }
+
+  return posthogServerClient;
+}
+
+/**
+ * Server-side analytics helper for PostHog.
+ * Similar pattern to the client-side useAnalytics hook.
+ */
+export const analytics = {
+  /**
+   * Capture an analytic event server-side.
+   *
+   * @param distinctId The user's unique identifier (typically email or userId).
+   * @param event The event name.
+   * @param properties Properties to attach to the event.
+   */
+  capture: async ({
+    distinctId,
+    event,
+    properties,
+  }: {
+    distinctId: string;
+    event: string;
+    properties?: Record<string, unknown>;
+  }): Promise<void> => {
+    const client = getPostHogServerClient();
+
+    if (!client) {
+      return;
+    }
+
+    client.capture({
+      distinctId,
+      event,
+      properties,
+    });
+
+    // Flush immediately to ensure event is sent before response
+    await client.flush();
+  },
+
+  /**
+   * Identify a user server-side.
+   *
+   * @param distinctId The user's unique identifier (typically email or userId).
+   * @param properties User properties to set.
+   */
+  identify: async ({
+    distinctId,
+    properties,
+  }: {
+    distinctId: string;
+    properties?: Record<string, unknown>;
+  }): Promise<void> => {
+    const client = getPostHogServerClient();
+
+    if (!client) {
+      return;
+    }
+
+    client.identify({
+      distinctId,
+      properties,
+    });
+
+    await client.flush();
+  },
+};

package-lock.json

@@ -113,6 +113,7 @@
         "pdf-lib": "^1.17.1",
         "postcss": "^8.5.6",
         "posthog-js": "^1.336.1",
+        "posthog-node": "^5.21.2",
         "react": "^18.3.1",
         "react-colorful": "^5.6.1",
         "react-day-picker": "^8.10.1",
@@ -17590,6 +17591,27 @@
         "node": ">=14"
       }
     },
+    "node_modules/posthog-node": {
+      "version": "5.21.2",
+      "resolved": "https://registry.npmjs.org/posthog-node/-/posthog-node-5.21.2.tgz",
+      "integrity": "sha512-Jehlu0KguL1LLyUczCt86OtA5INmeStK3zcgbv1BSyMcNxs0HP3GQogBrYhwhqHsk6JopiFFVpJyZEoXOUMhGw==",
+      "license": "MIT",
+      "dependencies": {
+        "@posthog/core": "1.10.0"
+      },
+      "engines": {
+        "node": ">=20"
+      }
+    },
+    "node_modules/posthog-node/node_modules/@posthog/core": {
+      "version": "1.10.0",
+      "resolved": "https://registry.npmjs.org/@posthog/core/-/core-1.10.0.tgz",
+      "integrity": "sha512-Xk3JQ+cdychsvftrV3G9ZrN9W329lbyFW0pGJXFGKFQf8qr4upw2SgNg9BVorjSrfhoXZRnJGt/uNF4nGFBL5A==",
+      "license": "MIT",
+      "dependencies": {
+        "cross-spawn": "^7.0.6"
+      }
+    },
     "node_modules/preact": {
       "version": "10.28.2",
       "resolved": "https://registry.npmjs.org/preact/-/preact-10.28.2.tgz",

package.json

@@ -124,6 +124,7 @@
     "pdf-lib": "^1.17.1",
     "postcss": "^8.5.6",
     "posthog-js": "^1.336.1",
+    "posthog-node": "^5.21.2",
     "react": "^18.3.1",
     "react-colorful": "^5.6.1",
     "react-day-picker": "^8.10.1",

pages/api/teams/[teamId]/invitations/accept.ts

@@ -3,7 +3,7 @@ import { NextApiRequest, NextApiResponse } from "next";
 import { authOptions } from "@/pages/api/auth/[...nextauth]";
 import { getServerSession } from "next-auth";
 
-import { identifyUser, trackAnalytics } from "@/lib/analytics";
+import { analytics, identifyUser, trackAnalytics } from "@/lib/analytics";
 import { errorhandler } from "@/lib/errorHandler";
 import prisma from "@/lib/prisma";
 import { CustomUser } from "@/lib/types";
@@ -120,6 +120,16 @@ export default async function handle(
         teamId: teamId,
       });
 
+      // Track in PostHog
+      await analytics.capture({
+        distinctId: invitation.email,
+        event: "Team Member Invitation Accepted",
+        properties: {
+          teamId: teamId,
+          userId: userId,
+        },
+      });
+
       // delete the invitation record after user is successfully added to the team
       await prisma.invitation.delete({
         where: {