From 76bee93338066d2a4842c5116f42ee8679a91657 Mon Sep 17 00:00:00 2001
From: John Costa <johncosta027@gmail.com>
Date: Mon, 30 Jun 2025 20:44:56 +0100
Subject: [PATCH] fix: challenge

---
 src/lib/twitch.ts                 | 19 +++++++++++++++++++
 src/routes/api/webhook/+server.ts | 12 ++++++++----
 2 files changed, 27 insertions(+), 4 deletions(-)

diff --git a/src/lib/twitch.ts b/src/lib/twitch.ts
index 71d7717..28c5ab7 100644
--- a/src/lib/twitch.ts
+++ b/src/lib/twitch.ts
@@ -21,6 +21,23 @@ type TwitchSubscribeBody = {
     };
 };
 
+export const twitchChallengeEvent = z.object({
+    challenge: z.string(),
+    subscription: z.object({
+        id: z.string(),
+        status: z.enum(['webhook_callback_verification_pending']),
+        type: z.enum(['channel.subscribe']),
+        version: z.string(),
+        condition: z.object({ broadcaster_user_id: z.string() }),
+        transport: z.object({
+            method: z.enum(['webhook']),
+            callback: z.string(),
+        }),
+        created_at: z.string(),
+        cost: z.number(),
+    })
+});
+
 // Not the complete event, but the information we need.
 export const twitchFollowEvent = z.object({
     subscription: z.object({
@@ -31,6 +48,8 @@ export const twitchFollowEvent = z.object({
     }),
 });
 
+export const twitchEvent = z.union([twitchFollowEvent, twitchChallengeEvent]);
+
 /*
  *curl -X POST 'https://api.twitch.tv/helix/eventsub/subscriptions' \
 -H 'Authorization: Bearer 2gbdx6oar67tqtcmt49t3wpcgycthx' \
diff --git a/src/routes/api/webhook/+server.ts b/src/routes/api/webhook/+server.ts
index 12451b9..160b91f 100644
--- a/src/routes/api/webhook/+server.ts
+++ b/src/routes/api/webhook/+server.ts
@@ -1,7 +1,7 @@
 import { createHmac, timingSafeEqual } from "node:crypto";
 import type { RequestHandler } from "@sveltejs/kit";
 import { HASH_SECRET } from "$env/static/private";
-import { twitchFollowEvent } from "$lib/twitch";
+import { twitchChallengeEvent, twitchFollowEvent } from "$lib/twitch";
 import { client } from "$lib";
 const getHmacMessage = (request: Request, body: string): string => {
     return (
@@ -42,9 +42,13 @@ export const fallback: RequestHandler = async ({ request }) => {
         console.log(jsonBody);
         const event = twitchFollowEvent.safeParse(jsonBody);
         if (!event.success) {
-            console.log("Not a follow event");
-            console.log(event.error);
-            return new Response();
+            const stuff = twitchChallengeEvent.safeParse(jsonBody);
+            if (!stuff.success) {
+                console.log("unknown event!!");
+                return new Response();
+            }
+
+            return new Response(stuff.data.challenge);
         }
 
         const { user_name } = event.data.event;