Support transcript files for video XBlocks in Blockstore

openedx/core/djangoapps/content_libraries/tests/test_static_assets.py

@@ -13,6 +13,16 @@ SVG_DATA = """<svg xmlns="http://www.w3.org/2000/svg" height="30" width="100">
   <text x="0" y="15" fill="red">SVG is 🔥</text>
 </svg>""".encode('utf-8')
 
+# part of an .srt transcript file
+TRANSCRIPT_DATA = """1
+00:00:00,260 --> 00:00:01,510
+Welcome to edX.
+
+2
+00:00:01,510 --> 00:00:04,480
+I'm Anant Agarwal, I'm the president of edX,
+""".encode('utf-8')
+
 
 class ContentLibrariesStaticAssetsTest(ContentLibrariesRestApiTest):
     """
@@ -111,3 +121,49 @@ class ContentLibrariesStaticAssetsTest(ContentLibrariesRestApiTest):
         # 'a////////b' is not allowed
         file_name = "a////////b"
         self._set_library_block_asset(block_id, file_name, SVG_DATA, expect_response=400)
+
+    def test_video_transcripts(self):
+        """
+        Test that video blocks can read transcript files out of blockstore.
+        """
+        library = self._create_library(slug="transcript-test-lib", title="Transcripts Test Library")
+        block = self._add_block_to_library(library["id"], "video", "video1")
+        block_id = block["id"]
+        self._set_library_block_olx(block_id, """
+            <video
+                youtube_id_1_0="3_yD_cEKoCk"
+                display_name="Welcome Video with Transcript"
+                download_track="true"
+                transcripts='{"en": "3_yD_cEKoCk-en.srt"}'
+            />
+        """)
+        # Upload the transcript file
+        self._set_library_block_asset(block_id, "3_yD_cEKoCk-en.srt", TRANSCRIPT_DATA)
+
+        transcript_handler_url = self._get_block_handler_url(block_id, "transcript")
+
+        def check_sjson():
+            """
+            Call the handler endpoint which the video player uses to load the transcript as SJSON
+            """
+            url = transcript_handler_url + 'translation/en'
+            response = self.client.get(url)
+            self.assertEqual(response.status_code, 200)
+            self.assertIn("Welcome to edX", response.content.decode('utf-8'))
+
+        def check_download():
+            """
+            Call the handler endpoint which the video player uses to download the transcript SRT file
+            """
+            url = transcript_handler_url + 'download'
+            response = self.client.get(url)
+            self.assertEqual(response.status_code, 200)
+            self.assertEqual(response.content, TRANSCRIPT_DATA)
+
+        check_sjson()
+        check_download()
+        # Publish the OLX and the transcript file, since published data gets
+        # served differently by Blockstore and we should test that too.
+        self._commit_library_changes(library["id"])
+        check_sjson()
+        check_download()