Introduce release_timestamp meta field (refs #28386)

youtube_dl/YoutubeDL.py

@@ -1511,14 +1511,18 @@ class YoutubeDL(object):
         if 'display_id' not in info_dict and 'id' in info_dict:
             info_dict['display_id'] = info_dict['id']
 
-        if info_dict.get('upload_date') is None and info_dict.get('timestamp') is not None:
-            # Working around out-of-range timestamp values (e.g. negative ones on Windows,
-            # see http://bugs.python.org/issue1646728)
-            try:
-                upload_date = datetime.datetime.utcfromtimestamp(info_dict['timestamp'])
-                info_dict['upload_date'] = upload_date.strftime('%Y%m%d')
-            except (ValueError, OverflowError, OSError):
-                pass
+        for ts_key, date_key in (
+                ('timestamp', 'upload_date'),
+                ('release_timestamp', 'release_date'),
+        ):
+            if info_dict.get(date_key) is None and info_dict.get(ts_key) is not None:
+                # Working around out-of-range timestamp values (e.g. negative ones on Windows,
+                # see http://bugs.python.org/issue1646728)
+                try:
+                    upload_date = datetime.datetime.utcfromtimestamp(info_dict[ts_key])
+                    info_dict[date_key] = upload_date.strftime('%Y%m%d')
+                except (ValueError, OverflowError, OSError):
+                    pass
 
         # Auto generate title fields corresponding to the *_number fields when missing
         # in order to always have clean titles. This is very common for TV series.

youtube_dl/extractor/common.py

@@ -230,8 +230,10 @@ class InfoExtractor(object):
     uploader:       Full name of the video uploader.
     license:        License name the video is licensed under.
     creator:        The creator of the video.
+    release_timestamp: UNIX timestamp of the moment the video was released.
     release_date:   The date (YYYYMMDD) when the video was released.
-    timestamp:      UNIX timestamp of the moment the video became available.
+    timestamp:      UNIX timestamp of the moment the video became available
+                    (uploaded).
     upload_date:    Video upload date (YYYYMMDD).
                     If not explicitly set, calculated from timestamp.
     uploader_id:    Nickname or id of the video uploader.