feat: load video poster from Educast videos

nau_openedx_extensions/apps.py

@@ -40,4 +40,17 @@ def ready(self):
         """
         Method to perform actions after apps registry is ended
         """
+        # Override the default Video xBlock the _poster private function.
+        # Override the class was giving more work because of the html dependencies
+        # was being loaded from the new package. So it was more easy just replace the
+        # method implementation.
+        from xmodule.video_block.video_block import \
+            VideoBlock  # pylint: disable=import-error,import-outside-toplevel # noqa
+
         from nau_openedx_extensions import signals  # pylint: disable=import-outside-toplevel,unused-import # noqa
+        from nau_openedx_extensions.xblocks.video_block import \
+            get_educast_poster_factory  # pylint: disable=import-outside-toplevel # noqa
+
+        # Replace the method in the original VideoBlock class
+        prev_poster_func = VideoBlock._poster  # pylint: disable=protected-access
+        VideoBlock._poster = get_educast_poster_factory(prev_poster_func)  # pylint: disable=protected-access

nau_openedx_extensions/xblocks/tests/test_video_block.py

@@ -0,0 +1,85 @@
+"""
+Test cases for the customized VideoBlock _poster method for Educast videos.
+"""
+from django.test import TestCase
+
+from nau_openedx_extensions.xblocks.video_block import get_educast_poster_factory
+
+
+class FakeVideoBlock():
+    """
+    A fake VideoBlock XBlock class for testing
+    """
+    def __init__(self):
+        self.html5_sources = {}
+
+
+class TestVideoBlock(TestCase):
+    """
+    Test cases for the customized VideoBlock _poster method for Educast videos.
+    """
+    def test_get_educast_poster_https(self):
+        """
+        Test the customized _poster method for VideoBlock.
+        """
+        # Create a mock previous _poster method
+        def mock_prev_poster(self):  # pylint: disable=unused-argument
+            return None
+
+        # Create the customized _poster method
+        customized_poster_method = get_educast_poster_factory(mock_prev_poster)
+
+        # Create an instance of VideoBlock and set html5_sources
+        video_block = FakeVideoBlock()
+        video_block.html5_sources = ['https://dev.educast.fccn.pt/vod/clips/bum66sthd/streaming.m3u8']
+
+        # Call the customized _poster method
+        poster_url = customized_poster_method(video_block)
+
+        # Verify the poster URL is as expected
+        expected_url = 'https://dev.educast.fccn.pt/img/clips/bum66sthd/delivery/cover'
+        self.assertEqual(poster_url, expected_url)
+
+    def test_get_educast_poster_http(self):
+        """
+        Test the customized _poster method for VideoBlock.
+        """
+        # Create a mock previous _poster method
+        def mock_prev_poster(self):  # pylint: disable=unused-argument
+            return None
+
+        # Create the customized _poster method
+        customized_poster_method = get_educast_poster_factory(mock_prev_poster)
+
+        # Create an instance of VideoBlock and set html5_sources
+        video_block = FakeVideoBlock()
+        video_block.html5_sources = ['http://educast.fccn.pt/vod/clips/fdgfdgfdgfdg/streaming.m3u8']
+
+        # Call the customized _poster method
+        poster_url = customized_poster_method(video_block)
+
+        # Verify the poster URL is as expected
+        expected_url = 'http://educast.fccn.pt/img/clips/fdgfdgfdgfdg/delivery/cover'
+        self.assertEqual(poster_url, expected_url)
+
+    def test_get_educast_poster_no_protocol(self):
+        """
+        Test the customized _poster method for VideoBlock.
+        """
+        # Create a mock previous _poster method
+        def mock_prev_poster(self):  # pylint: disable=unused-argument
+            return None
+
+        # Create the customized _poster method
+        customized_poster_method = get_educast_poster_factory(mock_prev_poster)
+
+        # Create an instance of VideoBlock and set html5_sources
+        video_block = FakeVideoBlock()
+        video_block.html5_sources = ['//educast.fccn.pt/vod/clips/aaaaaa/streaming.m3u8']
+
+        # Call the customized _poster method
+        poster_url = customized_poster_method(video_block)
+
+        # Verify the poster URL is as expected
+        expected_url = '//educast.fccn.pt/img/clips/aaaaaa/delivery/cover'
+        self.assertEqual(poster_url, expected_url)

nau_openedx_extensions/xblocks/video_block.py

@@ -0,0 +1,31 @@
+"""
+Custom video block extensions for NAU Open edX.
+"""
+import re
+
+
+def get_educast_poster_factory(prev_poster_func):
+    """
+    Factory to create a customized _poster method for VideoBlock.
+    This allows us to inject custom logic while retaining access to the original method.
+    """
+
+    def get_educast_poster(self):
+        """
+        Override the default poster URL logic to customize the poster image.
+        """
+        poster_url = prev_poster_func(self)
+        if not poster_url and self.html5_sources:
+            video_src = next(iter(self.html5_sources), None)
+            is_educast = 'educast.fccn.pt' in video_src  # to work for both educast staging and production
+            if is_educast:
+                # from video src like https://staging.educast.fccn.pt/vod/clips/bum66sthd/streaming.m3u8
+                # extract the server base url https://educast.fccn.pt or http://educast.fccn.pt or //educast.fccn.pt
+                server_base_url = re.match(r'^(https?://[^/]+|//[^/]+)', video_src).group(1)
+                # extract the educast video id like bumu66sthd
+                educast_video_id = re.search(r'/clips/([^/]+)/', video_src).group(1)
+                # construct poster url like https://educast.fccn.pt/img/clips/jpojtray/delivery/cover
+                poster_url = f"{server_base_url}/img/clips/{educast_video_id}/delivery/cover"
+        return poster_url
+
+    return get_educast_poster