[ie/twitch] Improve error handling (#13618)

Authored by: bashonly

yt_dlp/extractor/twitch.py

@@ -6,6 +6,7 @@ import re
 import urllib.parse
 
 from .common import InfoExtractor
+from ..networking.exceptions import HTTPError
 from ..utils import (
     ExtractorError,
     UserNotLive,
@@ -188,6 +189,7 @@ class TwitchBaseIE(InfoExtractor):
         }] if thumbnail else None
 
     def _extract_twitch_m3u8_formats(self, path, video_id, token, signature, live_from_start=False):
+        try:
             formats = self._extract_m3u8_formats(
                 f'{self._USHER_BASE}/{path}/{video_id}.m3u8', video_id, 'mp4', query={
                     'allow_source': 'true',
@@ -201,6 +203,25 @@ class TwitchBaseIE(InfoExtractor):
                     'sig': signature,
                     'token': token,
                 })
+        except ExtractorError as e:
+            if (
+                not isinstance(e.cause, HTTPError)
+                or e.cause.status != 403
+                or e.cause.response.get_header('content-type') != 'application/json'
+            ):
+                raise
+
+            error_info = traverse_obj(e.cause.response.read(), ({json.loads}, 0, {dict})) or {}
+            if error_info.get('error_code') in ('vod_manifest_restricted', 'unauthorized_entitlements'):
+                common_msg = 'access to this subscriber-only content'
+                if self._get_cookies('https://gql.twitch.tv').get('auth-token'):
+                    raise ExtractorError(f'Your account does not have {common_msg}', expected=True)
+                self.raise_login_required(f'You must be logged into an account that has {common_msg}')
+
+            if error_msg := join_nonempty('error_code', 'error', from_dict=error_info, delim=': '):
+                raise ExtractorError(error_msg, expected=True)
+            raise
+
         for fmt in formats:
             if fmt.get('vcodec') and fmt['vcodec'].startswith('av01'):
                 # mpegts does not yet have proper support for av1