Update app.py

app.py

@@ -40,6 +40,8 @@ def try_download_transcript(video_id):
         return None
 
 def download_audio_youtube(url, output_path="audio.wav", cookies_path=None):
+    import subprocess
+
     fallback_video_path = "fallback_video.mp4"
 
     ydl_opts = {
@@ -48,6 +50,7 @@ def download_audio_youtube(url, output_path="audio.wav", cookies_path=None):
         "user_agent": "com.google.android.youtube/17.31.35 (Linux; U; Android 11)",
         "compat_opts": ["allow_unplayable_formats"]
     }
+
     if cookies_path:
         ydl_opts["cookiefile"] = cookies_path
 
@@ -55,7 +58,20 @@ def download_audio_youtube(url, output_path="audio.wav", cookies_path=None):
         with yt_dlp.YoutubeDL(ydl_opts) as ydl:
             ydl.download([url])
     except Exception as e:
-        raise RuntimeError(f"yt-dlp failed: {e}")
+        # On failure, run yt-dlp in subprocess to list formats
+        try:
+            list_cmd = ["yt-dlp", "-F", url]
+            if cookies_path:
+                list_cmd += ["--cookies", cookies_path]
+            result = subprocess.run(list_cmd, capture_output=True, text=True, timeout=15)
+            formats = result.stdout or "No formats found."
+        except Exception as format_err:
+            formats = f"⚠️ Could not list formats due to: {format_err}"
+
+        raise RuntimeError(
+            f"yt-dlp failed: {e}\n\n"
+            f"Available formats for this video:\n\n{formats}"
+        )
 
     return extract_audio_from_video(fallback_video_path, audio_path=output_path)