added check if any transcripts are actually available

youtube_transcript_api/__init__.py

@@ -1,3 +1,11 @@
 from ._api import YouTubeTranscriptApi
 from ._transcripts import TranscriptList, Transcript
-from ._errors import TranscriptsDisabled, NoTranscriptFound, CouldNotRetrieveTranscript, VideoUnavailable
+from ._errors import (
+    TranscriptsDisabled,
+    NoTranscriptFound,
+    CouldNotRetrieveTranscript,
+    VideoUnavailable,
+    NotTranslatable,
+    TranslationLanguageNotAvailable,
+    NoTranscriptAvailable,
+)

youtube_transcript_api/_errors.py

@@ -43,6 +43,10 @@ class TranscriptsDisabled(CouldNotRetrieveTranscript):
     CAUSE_MESSAGE = 'Subtitles are disabled for this video'
 
 
+class NoTranscriptAvailable(CouldNotRetrieveTranscript):
+    CAUSE_MESSAGE = 'No transcripts are available for this video'
+
+
 class NotTranslatable(CouldNotRetrieveTranscript):
     CAUSE_MESSAGE = 'The requested language is not translatable'
 

youtube_transcript_api/_transcripts.py

@@ -13,7 +13,12 @@ import re
 
 from ._html_unescaping import unescape
 from ._errors import (
-    VideoUnavailable, NoTranscriptFound, TranscriptsDisabled, NotTranslatable, TranslationLanguageNotAvailable
+    VideoUnavailable,
+    NoTranscriptFound,
+    TranscriptsDisabled,
+    NotTranslatable,
+    TranslationLanguageNotAvailable,
+    NoTranscriptAvailable,
 )
 from ._settings import WATCH_URL
 
@@ -38,9 +43,14 @@ class TranscriptListFetcher():
 
             raise TranscriptsDisabled(video_id)
 
-        return json.loads(splitted_html[1].split(',"videoDetails')[0].replace('\n', ''))[
-            'playerCaptionsTracklistRenderer'
-        ]
+        captions_json = json.loads(
+            splitted_html[1].split(',"videoDetails')[0].replace('\n', '')
+        )['playerCaptionsTracklistRenderer']
+
+        if 'captionTracks' not in captions_json:
+            raise NoTranscriptAvailable(video_id)
+
+        return captions_json
 
     def _fetch_html(self, video_id):
         return self._http_client.get(WATCH_URL.format(video_id=video_id)).text.replace(

youtube_transcript_api/test/test_api.py

@@ -5,7 +5,13 @@ import os
 
 import httpretty
 
-from youtube_transcript_api import YouTubeTranscriptApi, VideoUnavailable, NoTranscriptFound, TranscriptsDisabled
+from youtube_transcript_api import (
+    YouTubeTranscriptApi,
+    TranscriptsDisabled,
+    NoTranscriptFound,
+    VideoUnavailable,
+    NoTranscriptAvailable,
+)
 
 
 def load_asset(filename):
@@ -88,6 +94,16 @@ class TestYouTubeTranscriptApi(TestCase):
         with self.assertRaises(NoTranscriptFound):
             YouTubeTranscriptApi.get_transcript('GJLlxj_dtq8', languages=['cz'])
 
+    def test_get_transcript__exception_if_no_transcript_available(self):
+        httpretty.register_uri(
+            httpretty.GET,
+            'https://www.youtube.com/watch',
+            body=load_asset('youtube_no_transcript_available.html.static')
+        )
+
+        with self.assertRaises(NoTranscriptAvailable):
+            YouTubeTranscriptApi.get_transcript('MwBPvcYFY2E')
+
     def test_get_transcripts(self):
         video_id_1 = 'video_id_1'
         video_id_2 = 'video_id_2'