fix: error seen when deleting a component used in a container (requires API change) [FC-0117]

openedx/core/djangoapps/content/search/documents.py

@@ -12,7 +12,7 @@
 from opaque_keys.edx.keys import ContainerKey, LearningContextKey, OpaqueKey, UsageKey
 from opaque_keys.edx.locator import LibraryCollectionLocator, LibraryContainerLocator
 from openedx_content import api as content_api
 from openedx_content.models_api import Collection, Section, Subsection, Unit
 from rest_framework.exceptions import NotFound
 
 from openedx.core.djangoapps.content.search.models import SearchAccess
@@ -627,42 +627,21 @@
         log.error(f"Container {container_key} not found")
         return doc
 
-    draft_children = lib_api.get_container_children(
-        container_key,
-        published=False,
-    )
+    draft_children = lib_api.get_container_children_v2(container_key, published=False)
     publish_status = PublishStatus.published
     if container.last_published is None:
         publish_status = PublishStatus.never
     elif container.has_unpublished_changes:
         publish_status = PublishStatus.modified
 
-    container_type_code = container_key.container_type
-
-    def get_child_keys(children) -> list[str]:
-        match container_type_code:
-            case Unit.type_code:
-                return [
-                    str(child.usage_key)
-                    for child in children
-                ]
-            case Subsection.type_code | Section.type_code:
-                return [
-                    str(child.container_key)
-                    for child in children
-                ]
-
-    def get_child_names(children) -> list[str]:
-        return [child.display_name for child in children]
-
     doc.update({
         Fields.display_name: container.display_name,
         Fields.created: container.created.timestamp(),
         Fields.modified: container.modified.timestamp(),
         Fields.num_children: len(draft_children),
         Fields.content: {
-            Fields.child_usage_keys: get_child_keys(draft_children),
-            Fields.child_display_names: get_child_names(draft_children),
+            Fields.child_usage_keys: [str(child.key) for child in draft_children],
+            Fields.child_display_names: [child.display_name for child in draft_children],
         },
         Fields.publish_status: publish_status,
         Fields.last_published: container.last_published.timestamp() if container.last_published else None,
@@ -672,16 +651,13 @@
         doc[Fields.breadcrumbs] = [{"display_name": library.title}]
 
     if container.published_version_num is not None:
-        published_children = lib_api.get_container_children(
-            container_key,
-            published=True,
-        )
+        published_children = lib_api.get_container_children_v2(container_key, published=True)
         doc[Fields.published] = {
             Fields.published_display_name: container.published_display_name,
             Fields.published_num_children: len(published_children),
             Fields.published_content: {
-                Fields.child_usage_keys: get_child_keys(published_children),
-                Fields.child_display_names: get_child_names(published_children),
+                Fields.child_usage_keys: [str(child.key) for child in published_children],
+                Fields.child_display_names: [child.display_name for child in published_children],
             },
         }
 

openedx/core/djangoapps/content_libraries/api/block_metadata.py

@@ -46,7 +46,12 @@ class LibraryXBlockMetadata(PublishableItem):
     usage_key: LibraryUsageLocatorV2
 
     @classmethod
-    def from_component(cls, library_key, component, associated_collections=None):
+    def from_component(
+        cls,
+        library_key: LibraryLocatorV2,
+        component,
+        associated_collections=None,
+    ) -> LibraryXBlockMetadata:
         """
         Construct a LibraryXBlockMetadata from a Component object.
         """

openedx/core/djangoapps/content_libraries/api/containers.py

@@ -2,44 +2,47 @@
 API for containers (Sections, Subsections, Units) in Content Libraries
 """
 
 from __future__ import annotations
 
 import logging
 import operator
 import typing
+from dataclasses import dataclass
 from datetime import datetime, timezone
 from functools import cache
+from typing_extensions import deprecated
 from uuid import UUID, uuid4
 
 from django.core.exceptions import ObjectDoesNotExist
 from django.db.models import F
 from django.utils.text import slugify
 from opaque_keys.edx.locator import LibraryContainerLocator, LibraryLocatorV2, LibraryUsageLocatorV2
 from openedx_content import api as content_api
 from openedx_content.models_api import Container, PublishLogRecord
 from openedx_events.content_authoring.data import LibraryContainerData
 from openedx_events.content_authoring.signals import LIBRARY_CONTAINER_DELETED
 
 from ..models import ContentLibrary
 from .block_metadata import (
     LibraryHistoryContributor,
     LibraryHistoryEntry,
     LibraryPublishHistoryGroup,
     LibraryXBlockMetadata,
     direct_published_entity_from_record,
     get_entity_item_type,
+    library_component_usage_key,
     make_contributor,
     resolve_change_action,
 )
 from .container_metadata import (
     LIBRARY_ALLOWED_CONTAINER_TYPES,
     ContainerHierarchy,
     ContainerMetadata,
     get_container_from_key,
     get_entity_from_key,
     library_container_locator,
 )
 from .serializers import ContainerSerializer
 
 if typing.TYPE_CHECKING:
     from openedx.core.djangoapps.content_staging.api import UserClipboardData
@@ -48,9 +51,11 @@
 # 🛑 UNSTABLE: All APIs related to containers are unstable until we've figured
 #              out our approach to dynamic content (randomized, A/B tests, etc.)
 __all__ = [
+    "ContainerChildMetadata",
     "get_container",
     "create_container",
     "get_container_children",
+    "get_container_children_v2",
     "get_container_children_count",
     "update_container",
     "delete_container",
@@ -70,6 +75,15 @@
 log = logging.getLogger(__name__)
 
 
+@dataclass(frozen=True)
+class ContainerChildMetadata:
+    """
+    Class that represents limited metadata about a child entity of a container
+    """
+    display_name: str
+    key: LibraryUsageLocatorV2 | LibraryContainerLocator
+
+
 def get_container(
     container_key: LibraryContainerLocator,
     *,
@@ -196,14 +210,24 @@
     content_api.set_draft_version(container.id, container.versioning.latest.pk)
 
 
+@deprecated("Use `get_container_children_v2` instead.")
 def get_container_children(
     container_key: LibraryContainerLocator,
     *,
     published=False,
 ) -> list[LibraryXBlockMetadata | ContainerMetadata]:
     """
-    [ 🛑 UNSTABLE ] Get the entities contained in the given container
-    (e.g. the components/xblocks in a unit, units in a subsection, subsections in a section)
+    [ 🛑 DEPRECATED: use ``get_container_children_v2`` instead ]
+
+    Get the entities contained in the given container (e.g. the components in a
+    unit, units in a subsection, subsections in a section)
+
+    This deprecated API raises an exception if you use it to get the published
+    version of a container when some of the container's children have had their
+    draft versions deleted (but published still exists).
+    This is because the LibraryXBlockMetadata data structure is only designed to
+    hold information about components that have a draft version as well as an
+    optional published version. So use ``get_container_children_v2`` instead.
     """
     container = get_container_from_key(container_key)
 
@@ -218,6 +242,27 @@
     return result
 
 
+def get_container_children_v2(
+    container_key: LibraryContainerLocator, *,
+    published: bool,
+) -> list[ContainerChildMetadata]:
+    """
+    [ 🛑 UNSTABLE ] Get the entities contained in the given container (e.g. the
+    components/xblocks in a unit, units in a subsection, subsections in a section)
+    """
+    container = get_container_from_key(container_key)
+    result: list[ContainerChildMetadata] = []
+    for entry in content_api.get_entities_in_container(container, published=published):
+        if hasattr(entry.entity, "component"):  # the child is a Component
+            key = library_component_usage_key(container_key.lib_key, entry.entity.component)
+        else:
+            assert isinstance(entry.entity.container, Container)
+            key = library_container_locator(container_key.lib_key, entry.entity.container)
+        display_name = entry.entity_version.title
+        result.append(ContainerChildMetadata(display_name=display_name, key=key))
+    return result
+
+
 def get_container_children_count(
     container_key: LibraryContainerLocator,
     published=False,