feat: Python api and rest api for History log logic [FC-0123]

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

@@ -3,9 +3,11 @@
 """
 from __future__ import annotations
 from dataclasses import dataclass
+from datetime import datetime
 
 from django.utils.translation import gettext as _
 from opaque_keys.edx.locator import LibraryUsageLocatorV2
+from openedx.core.djangoapps.user_api.accounts.image_helpers import get_profile_image_urls_for_user
 from .libraries import (
     library_component_usage_key,
     PublishableItem,
@@ -15,6 +17,9 @@
 __all__ = [
     "LibraryXBlockMetadata",
     "LibraryXBlockStaticFile",
+    "LibraryComponentHistoryEntry",
+    "LibraryComponentContributor",
+    "LibraryComponentPublishHistoryGroup",
 ]
 
 
@@ -49,6 +54,7 @@ def from_component(cls, library_key, component, associated_collections=None):
             usage_key=usage_key,
             display_name=draft.title,
             created=component.created,
+            created_by=component.created_by.username if component.created_by else None,
             modified=draft.created,
             draft_version_num=draft.version_num,
             published_version_num=published.version_num if published else None,
@@ -64,6 +70,52 @@ def from_component(cls, library_key, component, associated_collections=None):
         )
 
 
+@dataclass(frozen=True)
+class LibraryComponentHistoryEntry:
+    """
+    One entry in the history of a library component.
+    """
+    changed_by: LibraryComponentContributor | None
+    changed_at: datetime
+    title: str  # title at time of change
+    block_type: str
+    action: str  # "edited" | "renamed"
+
+
+@dataclass(frozen=True)
+class LibraryComponentContributor:
+    """
+    A contributor in a publish history group, with profile image URLs.
+    """
+    username: str
+    profile_image_urls: dict  # {"full": str, "large": str, "medium": str, "small": str}
+
+    @classmethod
+    def from_user(cls, user, request=None) -> 'LibraryComponentContributor':
+        return cls(
+            username=user.username,
+            profile_image_urls=get_profile_image_urls_for_user(user, request),
+        )
+
+
+@dataclass(frozen=True)
+class LibraryComponentPublishHistoryGroup:
+    """
+    Summary of a publish event for a library component.
+
+    Each instance represents one PublishLogRecord for the component, and
+    includes the set of contributors who authored draft changes between the
+    previous publish and this one.
+    """
+    publish_log_uuid: str
+    published_by: object  # AUTH_USER_MODEL instance or None
+    published_at: datetime
+    title: str  # title at time of publish
+    block_type: str
+    contributors: list[LibraryComponentContributor]  # distinct authors of versions in this group
+    contributors_count: int
+
+
 @dataclass(frozen=True)
 class LibraryXBlockStaticFile:
     """

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

@@ -11,6 +11,7 @@
 from uuid import uuid4
 
 from django.conf import settings
+from django.contrib.auth import get_user_model
 from django.core.exceptions import ObjectDoesNotExist, ValidationError
 from django.core.validators import validate_unicode_slug
 from django.db import transaction
@@ -58,7 +59,13 @@
     InvalidNameError,
     LibraryBlockAlreadyExists,
 )
-from .block_metadata import LibraryXBlockMetadata, LibraryXBlockStaticFile
+from .block_metadata import (
+    LibraryComponentContributor,
+    LibraryComponentHistoryEntry,
+    LibraryComponentPublishHistoryGroup,
+    LibraryXBlockMetadata,
+    LibraryXBlockStaticFile,
+)
 from .containers import (
     create_container,
     get_container,
@@ -78,6 +85,7 @@
     from openedx.core.djangoapps.content_staging.api import StagedContentFileData
 
 log = logging.getLogger(__name__)
+User = get_user_model()
 
 # The public API is only the following symbols:
 __all__ = [
@@ -98,6 +106,9 @@
     "add_library_block_static_asset_file",
     "delete_library_block_static_asset_file",
     "publish_component_changes",
+    "get_library_component_draft_history",
+    "get_library_component_publish_history",
+    "get_library_component_publish_history_entries",
 ]
 
 
@@ -191,6 +202,156 @@ def get_library_block(usage_key: LibraryUsageLocatorV2, include_collections=Fals
     return xblock_metadata
 
 
+def get_library_component_draft_history(
+    usage_key: LibraryUsageLocatorV2,
+    request=None,
+) -> list[LibraryComponentHistoryEntry]:
+    """
+    Return the draft change history for a library component since its last publication,
+    ordered from most recent to oldest.
+
+    Raises ContentLibraryBlockNotFound if the component does not exist.
+    """
+    try:
+        component = get_component_from_usage_key(usage_key)
+    except ObjectDoesNotExist as exc:
+        raise ContentLibraryBlockNotFound(usage_key) from exc
+
+    records = list(content_api.get_entity_draft_history(component.publishable_entity))
+    changed_by_list = _resolve_contributors(
+        (record.draft_change_log.changed_by for record in records), request
+    )
+
+    entries = []
+    for record, changed_by in zip(records, changed_by_list):
+        version = record.new_version if record.new_version is not None else record.old_version
+        entries.append(LibraryComponentHistoryEntry(
+            changed_by=changed_by,
+            changed_at=record.draft_change_log.changed_at,
+            title=version.title if version is not None else "",
+            block_type=record.entity.component.component_type.name,
+            action=_resolve_component_change_action(record.old_version, record.new_version),
+        ))
+    return entries
+
+
+def _resolve_contributors(users, request=None) -> list[LibraryComponentContributor | None]:
+    """
+    Convert an iterable of User objects (possibly containing None) to a list of
+    LibraryComponentContributor.
+    """
+    users_list = list(users)
+    user_pks = list({user.pk for user in users_list if user is not None})
+    prefetched = {
+        user.pk: user
+        for user in User.objects.filter(pk__in=user_pks).select_related('profile')
+    } if user_pks else {}
+    return [
+        LibraryComponentContributor.from_user(prefetched.get(user.pk, user), request)
+        if user else None
+        for user in users_list
+    ]
+
+
+def _resolve_component_change_action(old_version, new_version) -> str:
+    if old_version and new_version and old_version.title != new_version.title:
+        return "renamed"
+    return "edited"
+
+
+def get_library_component_publish_history(
+    usage_key: LibraryUsageLocatorV2,
+    request=None,
+) -> list[LibraryComponentPublishHistoryGroup]:
+    """
+    Return the publish history of a library component as a list of groups.
+
+    Each group corresponds to one publish event (PublishLogRecord) and includes:
+    - who published and when
+    - the distinct set of contributors: users who authored draft changes between
+      the previous publish and this one (via DraftChangeLogRecord version bounds)
+
+    Groups are ordered most-recent-first. Returns [] if the component has never
+    been published.
+
+    Contributors are resolved using version bounds (old_version_num → new_version_num)
+    rather than timestamps to avoid clock-skew issues. old_version_num defaults to
+    0 for the very first publish. new_version_num is None for soft-delete publishes
+    (no PublishableEntityVersion is created on soft delete).
+    """
+    try:
+        component = get_component_from_usage_key(usage_key)
+    except ObjectDoesNotExist as exc:
+        raise ContentLibraryBlockNotFound(usage_key) from exc
+
+    entity = component.publishable_entity
+    publish_records = list(content_api.get_entity_publish_history(entity))
+
+    groups = []
+    for pub_record in publish_records:
+        # old_version is None only for the very first publish (entity had no prior published version)
+        old_version_num = pub_record.old_version.version_num if pub_record.old_version else 0
+        # new_version is None for soft-delete publishes (component deleted without a new draft version)
+        new_version_num = pub_record.new_version.version_num if pub_record.new_version else None
+
+        raw_contributors = list(content_api.get_entity_version_contributors(
+            entity,
+            old_version_num=old_version_num,
+            new_version_num=new_version_num,
+        ))
+
+        contributors = [c for c in _resolve_contributors(raw_contributors, request) if c is not None]
+
+        groups.append(LibraryComponentPublishHistoryGroup(
+            publish_log_uuid=str(pub_record.publish_log.uuid),
+            published_by=pub_record.publish_log.published_by,
+            published_at=pub_record.publish_log.published_at,
+            contributors=contributors,
+            title=pub_record.new_version.title if pub_record.new_version else "",
+            block_type=pub_record.entity.component.component_type.name,
+            contributors_count=len(contributors),
+        ))
+
+    return groups
+
+
+def get_library_component_publish_history_entries(
+    usage_key: LibraryUsageLocatorV2,
+    publish_log_uuid: str,
+    request=None,
+) -> list[LibraryComponentHistoryEntry]:
+    """
+    Return the individual draft change entries for a specific publish event.
+
+    Called lazily when the user expands a publish event in the UI. Entries are
+    the DraftChangeLogRecords that fall between the previous publish event and
+    this one, ordered most-recent-first.
+    """
+    try:
+        component = get_component_from_usage_key(usage_key)
+    except ObjectDoesNotExist as exc:
+        raise ContentLibraryBlockNotFound(usage_key) from exc
+
+    records = list(content_api.get_entity_publish_history_entries(
+        component.publishable_entity, publish_log_uuid
+    ))
+    changed_by_list = _resolve_contributors(
+        (record.draft_change_log.changed_by for record in records), request
+    )
+
+    entries = []
+    for record, changed_by in zip(records, changed_by_list):
+        version = record.new_version if record.new_version is not None else record.old_version
+        entries.append(LibraryComponentHistoryEntry(
+            changed_by=changed_by,
+            changed_at=record.draft_change_log.changed_at,
+            title=version.title if version is not None else "",
+            block_type=record.entity.component.component_type.name,
+            action=_resolve_component_change_action(record.old_version, record.new_version),
+        ))
+    return entries
+
+
 def set_library_block_olx(usage_key: LibraryUsageLocatorV2, new_olx_str: str) -> ComponentVersion:
     """
     Replace the OLX source of the given XBlock.
@@ -682,7 +843,6 @@ def import_staged_content_from_user_clipboard(library_key: LibraryLocatorV2, use
             now,
         )
 
-
 def get_or_create_olx_media_type(block_type: str) -> MediaType:
     """
     Get or create a MediaType for the block type.

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

@@ -213,6 +213,7 @@ class PublishableItem(LibraryItem):
     has_unpublished_changes: bool = False
     collections: list[CollectionMetadata] = dataclass_field(default_factory=list)
     can_stand_alone: bool = True
+    created_by: str | None = None
 
 
 @dataclass(frozen=True)

openedx/core/djangoapps/content_libraries/rest_api/blocks.py

@@ -140,6 +140,66 @@ def delete(self, request, usage_key_str):  # pylint: disable=unused-argument
         return Response({})
 
 
+@method_decorator(non_atomic_requests, name="dispatch")
+@view_auth_classes()
+class LibraryComponentDraftHistoryView(APIView):
+    """
+    View to get the draft change history of a library component.
+    """
+    serializer_class = serializers.LibraryComponentHistoryEntrySerializer
+
+    @convert_exceptions
+    def get(self, request, usage_key_str):
+        """
+        Get the draft change history for a library component since its last publication.
+        """
+        key = LibraryUsageLocatorV2.from_string(usage_key_str)
+        api.require_permission_for_library_key(key.lib_key, request.user, permissions.CAN_VIEW_THIS_CONTENT_LIBRARY)
+        history = api.get_library_component_draft_history(key, request=request)
+        return Response(self.serializer_class(history, many=True).data)
+
+
+@method_decorator(non_atomic_requests, name="dispatch")
+@view_auth_classes()
+class LibraryComponentPublishHistoryView(APIView):
+    """
+    View to get the publish history of a library component as a list of publish events.
+    """
+    serializer_class = serializers.LibraryComponentPublishHistoryGroupSerializer
+
+    @convert_exceptions
+    def get(self, request, usage_key_str):
+        """
+        Get the publish history for a library component, ordered most-recent-first.
+        """
+        key = LibraryUsageLocatorV2.from_string(usage_key_str)
+        api.require_permission_for_library_key(key.lib_key, request.user, permissions.CAN_VIEW_THIS_CONTENT_LIBRARY)
+        history = api.get_library_component_publish_history(key, request=request)
+        return Response(self.serializer_class(history, many=True).data)
+
+
+@method_decorator(non_atomic_requests, name="dispatch")
+@view_auth_classes()
+class LibraryComponentPublishHistoryEntriesView(APIView):
+    """
+    View to get the individual draft change entries for a specific publish event.
+    """
+    serializer_class = serializers.LibraryComponentHistoryEntrySerializer
+
+    @convert_exceptions
+    def get(self, request, usage_key_str, publish_log_uuid):
+        """
+        Get the draft change entries for a specific publish event, ordered most-recent-first.
+        """
+        key = LibraryUsageLocatorV2.from_string(usage_key_str)
+        api.require_permission_for_library_key(key.lib_key, request.user, permissions.CAN_VIEW_THIS_CONTENT_LIBRARY)
+        try:
+            entries = api.get_library_component_publish_history_entries(key, publish_log_uuid, request=request)
+        except ObjectDoesNotExist as exc:
+            raise NotFound(f"No publish event '{publish_log_uuid}' found for this component.") from exc
+        return Response(self.serializer_class(entries, many=True).data)
+
+
 @method_decorator(non_atomic_requests, name="dispatch")
 @view_auth_classes()
 class LibraryBlockAssetListView(APIView):