Add UnsupportedMediaType exception and checks for downloaders

gamdl/downloader/downloader.py

@@ -27,6 +27,7 @@ from .exceptions import (
     MediaFileExists,
     NotStreamable,
     SyncedLyricsOnly,
+    UnsupportedMediaType,
 )
 from .types import DownloadItem, UrlInfo
 
@@ -86,18 +87,27 @@ class AppleMusicDownloader:
                 raise NotStreamable(media_metadata["id"])
 
             if media_metadata["type"] in SONG_MEDIA_TYPE:
+                if not self.song_downloader:
+                    raise UnsupportedMediaType(media_metadata["type"])
+
                 download_item = await self.song_downloader.get_download_item(
                     media_metadata,
                     playlist_metadata,
                 )
 
             if media_metadata["type"] in MUSIC_VIDEO_MEDIA_TYPE:
+                if not self.music_video_downloader:
+                    raise UnsupportedMediaType(media_metadata["type"])
+
                 download_item = await self.music_video_downloader.get_download_item(
                     media_metadata,
                     playlist_metadata,
                 )
 
             if media_metadata["type"] in UPLOADED_VIDEO_MEDIA_TYPE:
+                if not self.uploaded_video_downloader:
+                    raise UnsupportedMediaType(media_metadata["type"])
+
                 download_item = await self.uploaded_video_downloader.get_download_item(
                     media_metadata,
                 )

gamdl/downloader/exceptions.py

@@ -25,3 +25,8 @@ class ExecutableNotFound(GamdlError):
 class SyncedLyricsOnly(GamdlError):
     def __init__(self):
         super().__init__("Only downloading synced lyrics is supported")
+
+
+class UnsupportedMediaType(GamdlError):
+    def __init__(self, media_type: str):
+        super().__init__(f"Unsupported media type: {media_type}")