Add support for channel version tokens on v1 public channel endpoint

contentcuration/contentcuration/management/commands/create_channel_versions.py

@@ -194,8 +194,8 @@ def handle(self, *args, **options):  # noqa: C901
                                 "non_distributable_licenses_included"
                             ),
                             "kind_count": pub_data.get("kind_count"),
-                            "size": int(channel.published_size),
-                            "resource_count": channel.total_resource_count,
+                            "size": int(pub_data.get("size", 0)),
+                            "resource_count": int(pub_data.get("resource_count", 0)),
                         },
                     )
 

contentcuration/contentcuration/migrations/0164_add_channel_info_snapshot_to_channelversion.py

@@ -0,0 +1,45 @@
+# Generated by Django 3.2.24 on 2026-03-24 18:10
+import django.db.models.deletion
+from django.db import migrations
+from django.db import models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("contentcuration", "0163_merge_20260320_1809"),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name="channelversion",
+            name="channel_description",
+            field=models.CharField(blank=True, max_length=400, null=True),
+        ),
+        migrations.AddField(
+            model_name="channelversion",
+            name="channel_language",
+            field=models.ForeignKey(
+                blank=True,
+                null=True,
+                on_delete=django.db.models.deletion.SET_NULL,
+                related_name="+",
+                to="contentcuration.language",
+            ),
+        ),
+        migrations.AddField(
+            model_name="channelversion",
+            name="channel_name",
+            field=models.CharField(blank=True, max_length=200, null=True),
+        ),
+        migrations.AddField(
+            model_name="channelversion",
+            name="channel_tagline",
+            field=models.CharField(blank=True, max_length=150, null=True),
+        ),
+        migrations.AddField(
+            model_name="channelversion",
+            name="channel_thumbnail_encoding",
+            field=models.JSONField(blank=True, default=dict),
+        ),
+    ]

contentcuration/contentcuration/models.py

@@ -1607,14 +1607,37 @@ class ChannelVersion(models.Model):
         blank=True,
     )
 
+    # Snapshot of the channel info at the time of creation.
+    channel_name = models.CharField(max_length=200, blank=True, null=True)
+    channel_description = models.CharField(max_length=400, blank=True, null=True)
+    channel_tagline = models.CharField(max_length=150, blank=True, null=True)
+    channel_thumbnail_encoding = JSONField(default=dict, blank=True)
+    channel_language = models.ForeignKey(
+        "Language",
+        null=True,
+        blank=True,
+        related_name="+",
+        on_delete=models.SET_NULL,
+    )
+
     class Meta:
         unique_together = ("channel", "version")
 
     def save(self, *args, **kwargs):
         if self.version is not None and self.version > self.channel.version:
             raise ValidationError("Version cannot be greater than channel version")
+
+        if self._state.adding and self.version == self.channel.version:
+            # When creating a new ChannelVersion for current channel version,
+            # snapshot the current channel info
+            self.channel_name = self.channel.name
+            self.channel_description = self.channel.description
+            self.channel_tagline = self.channel.tagline
+            self.channel_thumbnail_encoding = self.channel.thumbnail_encoding
+            self.channel_language = self.channel.language
+
         self.full_clean()
-        super(ChannelVersion, self).save(*args, **kwargs)
+        super().save(*args, **kwargs)
 
     def new_token(self):
         if not self.secret_token:

contentcuration/contentcuration/serializers.py

@@ -22,6 +22,22 @@ def no_field_eval_repr(self):
 serializers.ModelSerializer.__repr__ = no_field_eval_repr
 
 
+def get_thumbnail_encoding(channel):
+    """
+    Historically, we did not set channel.icon_encoding in the Studio database. We
+    only set it in the exported Kolibri sqlite db. So when Kolibri asks for the channel
+    information, fall back to the channel thumbnail data if icon_encoding is not set.
+    """
+    if channel.icon_encoding:
+        return channel.icon_encoding
+    if channel.thumbnail_encoding:
+        base64 = channel.thumbnail_encoding.get("base64")
+        if base64:
+            return base64
+
+    return None
+
+
 class PublicChannelSerializer(serializers.ModelSerializer):
     """
     Called by the public API, primarily used by Kolibri. Contains information more specific to Kolibri's needs.
@@ -41,19 +57,7 @@ def match_tokens(self, channel):
         )
 
     def get_thumbnail_encoding(self, channel):
-        """
-        Historically, we did not set channel.icon_encoding in the Studio database. We
-        only set it in the exported Kolibri sqlite db. So when Kolibri asks for the channel
-        information, fall back to the channel thumbnail data if icon_encoding is not set.
-        """
-        if channel.icon_encoding:
-            return channel.icon_encoding
-        if channel.thumbnail_encoding:
-            base64 = channel.thumbnail_encoding.get("base64")
-            if base64:
-                return base64
-
-        return None
+        return get_thumbnail_encoding(channel)
 
     def generate_kind_count(self, channel):
         return channel.published_kind_count and json.loads(channel.published_kind_count)

contentcuration/contentcuration/tests/test_models.py

@@ -31,6 +31,7 @@
 from contentcuration.models import FlagFeedbackEvent
 from contentcuration.models import generate_object_storage_name
 from contentcuration.models import Invitation
+from contentcuration.models import Language
 from contentcuration.models import License
 from contentcuration.models import object_storage_name
 from contentcuration.models import RecommendationsEvent
@@ -1814,3 +1815,105 @@ def test_version_cannot_exceed_channel_version(self):
         self.assertIn(
             "Version cannot be greater than channel version", str(context.exception)
         )
+
+    def test_save_snapshots_channel_info_when_version_matches_channel_version(self):
+        """Creating a ChannelVersion whose version equals channel.version should
+        automatically snapshot the channel's current name, description, tagline,
+        thumbnail_encoding, and language."""
+        lang = Language.objects.first()
+        # Use a queryset update to set channel fields without triggering on_update
+        # (which would call get_or_create and collide with the ChannelVersion we're
+        # about to create ourselves).
+        Channel.objects.filter(id=self.channel.id).update(
+            name="Snapshot Channel",
+            description="A channel to snapshot",
+            tagline="Learn something new",
+            thumbnail_encoding={"base64": "abc123"},
+            language=lang,
+        )
+        self.channel.refresh_from_db()
+
+        # setUp's self.channel.save() already auto-created a ChannelVersion for
+        # version 10 via on_update. Delete it so we can create a fresh one and
+        # observe the snapshot logic.
+        ChannelVersion.objects.filter(
+            channel=self.channel, version=self.channel.version
+        ).delete()
+
+        cv = ChannelVersion(
+            channel=self.channel,
+            version=self.channel.version,
+        )
+        cv.save()
+
+        cv.refresh_from_db()
+        self.assertEqual(cv.channel_name, self.channel.name)
+        self.assertEqual(cv.channel_description, self.channel.description)
+        self.assertEqual(cv.channel_tagline, self.channel.tagline)
+        self.assertEqual(cv.channel_thumbnail_encoding, self.channel.thumbnail_encoding)
+        self.assertEqual(cv.channel_language, self.channel.language)
+
+    def test_save_does_not_snapshot_when_version_differs_from_channel_version(self):
+        """Creating a ChannelVersion for an older version should NOT populate
+        the snapshot fields automatically."""
+        self.channel.name = "Current Name"
+        self.channel.save()
+
+        # version 5 is less than channel.version (10)
+        cv = ChannelVersion(
+            channel=self.channel,
+            version=5,
+        )
+        cv.save()
+
+        cv.refresh_from_db()
+        self.assertIsNone(cv.channel_name)
+        self.assertIsNone(cv.channel_description)
+        self.assertIsNone(cv.channel_tagline)
+        self.assertIsNone(cv.channel_language)
+
+    def test_save_does_not_re_snapshot_on_update(self):
+        """Updating an existing ChannelVersion (not adding) should NOT overwrite
+        the snapshot fields even if the channel info has changed."""
+        # setUp's self.channel.save() already created a ChannelVersion for version 10
+        # via on_update -> get_or_create. Reuse that existing object so we're
+        # testing a genuine update (not insert) path.
+        cv = ChannelVersion.objects.get(
+            channel=self.channel, version=self.channel.version
+        )
+        original_name = cv.channel_name
+
+        # Change the channel name via a queryset update so on_update is not called
+        # (avoiding a second get_or_create for the same version).
+        Channel.objects.filter(id=self.channel.id).update(name="Updated Channel Name")
+        self.channel.refresh_from_db()
+
+        cv.version_notes = "some notes"
+        cv.save()
+
+        cv.refresh_from_db()
+        # The snapshot should still reflect the name captured when cv was first created.
+        self.assertEqual(cv.channel_name, original_name)
+        self.assertNotEqual(cv.channel_name, "Updated Channel Name")
+
+    def test_save_snapshots_null_language_when_channel_has_no_language(self):
+        """When the channel has no language set, channel_language on the snapshot
+        should remain None."""
+        # Ensure no language on the channel via queryset update (bypasses on_update).
+        Channel.objects.filter(id=self.channel.id).update(language=None)
+        self.channel.refresh_from_db()
+
+        # Delete the ChannelVersion auto-created during setUp so we can insert a
+        # fresh one and observe the snapshot logic.
+        ChannelVersion.objects.filter(
+            channel=self.channel, version=self.channel.version
+        ).delete()
+
+        cv = ChannelVersion(
+            channel=self.channel,
+            version=self.channel.version,
+        )
+        cv.save()
+
+        cv.refresh_from_db()
+        self.assertIsNone(cv.channel_language)