[twitch] Pass v5 accept header and fix thumbnails extraction (closes #25531)

youtube_dl/extractor/twitch.py

@@ -21,6 +21,7 @@ from ..utils import (
     orderedSet,
     parse_duration,
     parse_iso8601,
+    qualities,
     try_get,
     unified_timestamp,
     update_url_query,
@@ -50,7 +51,10 @@ class TwitchBaseIE(InfoExtractor):
 
     def _call_api(self, path, item_id, *args, **kwargs):
         headers = kwargs.get('headers', {}).copy()
-        headers['Client-ID'] = self._CLIENT_ID
+        headers.update({
+            'Accept': 'application/vnd.twitchtv.v5+json; charset=UTF-8',
+            'Client-ID': self._CLIENT_ID,
+        })
         kwargs['headers'] = headers
         response = self._download_json(
             '%s/%s' % (self._API_BASE, path), item_id,
@@ -186,12 +190,27 @@ class TwitchItemBaseIE(TwitchBaseIE):
             is_live = False
         else:
             is_live = None
+        _QUALITIES = ('small', 'medium', 'large')
+        quality_key = qualities(_QUALITIES)
+        thumbnails = []
+        preview = info.get('preview')
+        if isinstance(preview, dict):
+            for thumbnail_id, thumbnail_url in preview.items():
+                thumbnail_url = url_or_none(thumbnail_url)
+                if not thumbnail_url:
+                    continue
+                if thumbnail_id not in _QUALITIES:
+                    continue
+                thumbnails.append({
+                    'url': thumbnail_url,
+                    'preference': quality_key(thumbnail_id),
+                })
         return {
             'id': info['_id'],
             'title': info.get('title') or 'Untitled Broadcast',
             'description': info.get('description'),
             'duration': int_or_none(info.get('length')),
-            'thumbnail': info.get('preview'),
+            'thumbnails': thumbnails,
             'uploader': info.get('channel', {}).get('display_name'),
             'uploader_id': info.get('channel', {}).get('name'),
             'timestamp': parse_iso8601(info.get('recorded_at')),