From c8b7ea81336c9e8d3e394e67a1ae5036f417a150 Mon Sep 17 00:00:00 2001
From: Tobias Lins <me@tobi.sh>
Date: Tue, 8 Aug 2023 13:11:52 +0200
Subject: [PATCH] Improved server side events (#92)

* Add more error logs

* rename to withSessionContext

* Throw error when no headers are found

* update version

* Update packages/web/src/server/index.ts

Co-authored-by: Chris <7249920+chriswdmr@users.noreply.github.com>

* Update packages/web/src/server/index.ts

Co-authored-by: Chris <7249920+chriswdmr@users.noreply.github.com>

---------

Co-authored-by: Chris <7249920+chriswdmr@users.noreply.github.com>
---
 apps/nextjs/app/api/edge/route.ts          |  5 ++---
 apps/nextjs/app/api/serverless/route.ts    |  5 ++---
 packages/web/package.json                  |  2 +-
 packages/web/src/server/index.ts           | 21 +++++++++++++++++----
 packages/web/src/server/request-context.ts |  2 +-
 5 files changed, 23 insertions(+), 12 deletions(-)

diff --git a/apps/nextjs/app/api/edge/route.ts b/apps/nextjs/app/api/edge/route.ts
index 45ed8d8..3c2ef21 100644
--- a/apps/nextjs/app/api/edge/route.ts
+++ b/apps/nextjs/app/api/edge/route.ts
@@ -1,5 +1,4 @@
-import { track } from '@vercel/analytics/server';
-import { withRequestContext } from '@vercel/analytics/server';
+import { withSessionContext, track } from '@vercel/analytics/server';
 
 export const runtime = 'edge';
 
@@ -12,4 +11,4 @@ async function handler() {
   return new Response('OK');
 }
 
-export const GET = withRequestContext(handler);
+export const GET = withSessionContext(handler);
diff --git a/apps/nextjs/app/api/serverless/route.ts b/apps/nextjs/app/api/serverless/route.ts
index 16a520b..9014bb1 100644
--- a/apps/nextjs/app/api/serverless/route.ts
+++ b/apps/nextjs/app/api/serverless/route.ts
@@ -1,5 +1,4 @@
-import { withRequestContext, track } from '@vercel/analytics/server';
-import { NextRequest } from 'next/server';
+import { withSessionContext, track } from '@vercel/analytics/server';
 
 async function handler() {
   await track('Serverless Event', {
@@ -9,4 +8,4 @@ async function handler() {
   return new Response('OK');
 }
 
-export const GET = withRequestContext(handler);
+export const GET = withSessionContext(handler);
diff --git a/packages/web/package.json b/packages/web/package.json
index f894502..a8bd700 100644
--- a/packages/web/package.json
+++ b/packages/web/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@vercel/analytics",
-  "version": "1.1.0-beta.2",
+  "version": "1.1.0-beta.3",
   "description": "Gain real-time traffic insights with Vercel Web Analytics",
   "keywords": [
     "analytics",
diff --git a/packages/web/src/server/index.ts b/packages/web/src/server/index.ts
index 84d0e98..6f09f97 100644
--- a/packages/web/src/server/index.ts
+++ b/packages/web/src/server/index.ts
@@ -3,7 +3,7 @@
 import type { AllowedPropertyValues } from '../types';
 import type { StorageData } from './request-context';
 
-export { withRequestContext } from './request-context';
+export { withSessionContext } from './request-context';
 
 const ENDPOINT = process.env.VERCEL_URL || process.env.VERCEL_ANALYTICS_URL;
 const ENV = process.env.NODE_ENV;
@@ -80,10 +80,22 @@ export async function track(
 
     const hasHeaders = Boolean(headers);
 
-    // eslint-disable-next-line @typescript-eslint/restrict-template-expressions
+    if (!hasHeaders) {
+      throw new Error(
+        'No session context found. Wrap your API route handler with `withSessionContext` or pass `request` or `headers` to the `track` function.',
+      );
+    }
+
+    if (!ENDPOINT) {
+      throw new Error(
+        '`process.env.VERCEL_URL` is not defined in your environment variables.',
+      );
+    }
+
     const promise = fetch(`https://${ENDPOINT}/_vercel/insights/event`, {
       headers: {
         'content-type': 'application/json',
+        // eslint-disable-next-line @typescript-eslint/no-unnecessary-condition -- The throwing is temporary until we add support for non Vercel hosted environments
         ...(hasHeaders
           ? {
               'user-agent': tmp['user-agent'] as string,
@@ -97,9 +109,10 @@ export async function track(
       body: JSON.stringify(body),
       method: 'POST',
     }).catch((err: unknown) => {
-      if (!(err instanceof Error)) return;
-      if ('response' in err) {
+      if (err instanceof Error && 'response' in err) {
         console.error(err.response);
+      } else {
+        console.error(err);
       }
     });
 
diff --git a/packages/web/src/server/request-context.ts b/packages/web/src/server/request-context.ts
index b7ebbf9..cf61079 100644
--- a/packages/web/src/server/request-context.ts
+++ b/packages/web/src/server/request-context.ts
@@ -4,7 +4,7 @@ export interface StorageData {
   request: Request;
 }
 
-export const withRequestContext =
+export const withSessionContext =
   <T extends Request>(next: (req: any, res: any) => Promise<Response | void>) =>
   async (request: T, secondParam: Response): Promise<Response | void> => {
     const asyncLocalStorage = new AsyncLocalStorage<StorageData>();