[Epidemic Sound] add support for separate tracks

youtube_dl/extractor/epidemicsound.py

@@ -2,12 +2,21 @@
 from __future__ import unicode_literals
 
 from .common import InfoExtractor
-from ..utils import unified_timestamp
+from ..utils import (
+    ExtractorError,
+    float_or_none,
+    txt_or_none,
+    unified_timestamp,
+    url_or_none,
+    traverse_obj,
+    str_or_none,
+    T,
+)
 
 
 class EpidemicSoundIE(InfoExtractor):
     _VALID_URL = r'https?://(?:www\.)?epidemicsound\.com/track/(?P<id>[0-9a-zA-Z]+)'
-    _TEST = {
+    _TESTS = [{
         'url': 'https://www.epidemicsound.com/track/yFfQVRpSPz/',
         'md5': 'd98ff2ddb49e8acab9716541cbc9dfac',
         'info_dict': {
@@ -20,18 +29,59 @@ class EpidemicSoundIE(InfoExtractor):
             'timestamp': 1415320353,
             'upload_date': '20141107',
         }
-    }
+    },
+        {
+            'url': 'https://www.epidemicsound.com/track/mj8GTTwsZd/',
+            'md5': 'c82b745890f9baf18dc2f8d568ee3830',
+            'info_dict': {
+                'id': 'mj8GTTwsZd',
+                'ext': 'mp3',
+                'tags': ["liquid drum n bass", "energetic"],
+                'title': 'Noplace',
+                'duration': 237,
+                'thumbnail': 'https://cdn.epidemicsound.com/curation-assets/commercial-release-cover-images/11138/3000x3000.jpg',
+                'timestamp': 1694426482,
+                'upload_date': '20230911',
+            }
+        },
+    ]
 
     def _real_extract(self, url):
         video_id = self._match_id(url)
         json_data = self._download_json('https://www.epidemicsound.com/json/track/' + video_id, video_id)
 
-        return {
-            'id': video_id,
-            'url': json_data.get('stems').get('full').get('lqMp3Url'),
-            'tags': json_data.get('metadataTags'),
-            'title': json_data.get('title'),
-            'duration': json_data.get('length'),
-            'timestamp': unified_timestamp(json_data.get('added')),
-            'thumbnail': json_data.get('imageUrl'),
-        }
+        if not traverse_obj(json_data, ('stems', Ellipsis)):
+            raise ExtractorError('No downloadable content found')
+
+        formats = list(reversed([
+            {
+                'format_id': str_or_none(key),
+                'url': url_or_none(value.get('lqMp3Url'))
+            } for key, value in json_data.get('stems').items()
+        ]))
+
+        for f in formats:
+            for key, value in f.items():
+                if value is None or key is None:
+                    del f
+
+        if len(formats) == 0:
+            raise ExtractorError('No downloadable content found')
+
+        info = traverse_obj(json_data, {
+            'tags': ('metadataTags', Ellipsis, T(txt_or_none)),
+            'title': ('title', T(txt_or_none)),
+            'duration': ('length', T(float_or_none)),
+            'timestamp': ('added', T(unified_timestamp)),
+            'thumbnail': ('imageUrl', T(url_or_none))})
+
+        info['id'] = video_id
+        info['formats'] = formats
+
+        if not info.get('tags'):
+            del info['tags']
+
+        if not info.get('title'):
+            raise ExtractorError('No title found')
+
+        return info