Merge pull request #48 from Juliusolsson05/fix/youtube-embed-parser

fix: use oEmbed to verify YouTube embeds

Author: Juliusolsson05

src/app/api/v1/perspectives/live-status/route.ts

@@ -5,7 +5,6 @@ import { err, ok } from '@/server/lib/api-utils';
 const CACHE_TTL = 600;
 const CANONICAL_VIDEO_RE = /<link rel="canonical" href="https:\/\/www\.youtube\.com\/watch\?v=([^"&]+)"/;
 const IS_LIVE_RE = /"isLive"\s*:\s*true/;
-const PLAYABLE_VIDEO_RE = /"playabilityStatus":\{"status":"OK","playableInEmbed":(true|false)[\s\S]{0,4000}?"videoId":"([^"]+)"/;
 
 type CacheEntry = {
   isLive: boolean;
@@ -16,42 +15,36 @@ type CacheEntry = {
 
 const cache = new Map<string, CacheEntry>();
 
-function escapeRegExp(value: string) {
-  return value.replace(/[.*+?^${}()|[\]\\]/g, '\\$&');
-}
-
-function parseLivePlayback(html: string) {
-  const canonicalVideoId = html.match(CANONICAL_VIDEO_RE)?.[1] ?? null;
-
-  if (canonicalVideoId) {
-    const canonicalPlayable = new RegExp(
-      `"playabilityStatus":\\{"status":"OK","playableInEmbed":(true|false)[\\s\\S]{0,4000}?"videoId":"${escapeRegExp(canonicalVideoId)}"`,
-    ).exec(html);
+async function isEmbeddableVideo(videoId: string) {
+  const oembedUrl = `https://www.youtube.com/oembed?url=https://www.youtube.com/watch?v=${videoId}&format=json`;
 
-    if (canonicalPlayable) {
-      return {
-        playableInEmbed: canonicalPlayable[1] === 'true',
-        videoId: canonicalPlayable[1] === 'true' ? canonicalVideoId : null,
-      };
-    }
+  try {
+    const res = await fetch(oembedUrl, {
+      headers: { 'User-Agent': 'Mozilla/5.0' },
+      signal: AbortSignal.timeout(8000),
+    });
 
-    return {
-      playableInEmbed: true,
-      videoId: canonicalVideoId,
-    };
+    return res.ok;
+  } catch {
+    return false;
   }
+}
 
-  const playableMatch = html.match(PLAYABLE_VIDEO_RE);
-  if (!playableMatch) {
+async function parseLivePlayback(html: string) {
+  const canonicalVideoId = html.match(CANONICAL_VIDEO_RE)?.[1] ?? null;
+
+  if (!canonicalVideoId) {
     return {
       playableInEmbed: false,
       videoId: null,
     };
   }
 
+  const playableInEmbed = await isEmbeddableVideo(canonicalVideoId);
+
   return {
-    playableInEmbed: playableMatch[1] === 'true',
-    videoId: playableMatch[1] === 'true' ? playableMatch[2] : null,
+    playableInEmbed,
+    videoId: playableInEmbed ? canonicalVideoId : null,
   };
 }
 
@@ -73,7 +66,7 @@ async function checkLiveStatus(handle: string): Promise<{ isLive: boolean; playa
     const html = await res.text();
     const isLive = IS_LIVE_RE.test(html);
     const playback = isLive
-      ? parseLivePlayback(html)
+      ? await parseLivePlayback(html)
       : { playableInEmbed: false, videoId: null };
     const playableInEmbed = playback.playableInEmbed;
     const videoId = playback.videoId;