Validation warning when no content matches configured filters

common/lib/xmodule/xmodule/library_content_module.py

@@ -361,6 +361,31 @@ class LibraryContentDescriptor(LibraryContentFields, MakoModuleDescriptor, XmlDe
         lib_tools.update_children(self, user_id, user_perms, update_db)
         return Response()
 
+    def _validate_library_version(self, validation, lib_tools, version, library_key):
+        latest_version = lib_tools.get_library_version(library_key)
+        if latest_version is not None:
+            if version is None or version != latest_version:
+                validation.set_summary(
+                    StudioValidationMessage(
+                        StudioValidationMessage.WARNING,
+                        _(u'This component is out of date. The library has new content.'),
+                        action_class='library-update-btn',  # TODO: change this to action_runtime_event='...' once the unit page supports that feature.
+                        action_label=_(u"↻ Update now")
+                    )
+                )
+                return False
+        else:
+            validation.set_summary(
+                StudioValidationMessage(
+                    StudioValidationMessage.ERROR,
+                    _(u'Library is invalid, corrupt, or has been deleted.'),
+                    action_class='edit-button',
+                    action_label=_(u"Edit Library List")
+                )
+            )
+            return False
+        return True
+
     def validate(self):
         """
         Validates the state of this Library Content Module Instance. This
@@ -381,30 +406,27 @@ class LibraryContentDescriptor(LibraryContentFields, MakoModuleDescriptor, XmlDe
             )
             return validation
         lib_tools = self.runtime.service(self, 'library_tools')
+        has_children_matching_filter = False
         for library_key, version in self.source_libraries:
-            latest_version = lib_tools.get_library_version(library_key)
-            if latest_version is not None:
-                if version is None or version != latest_version:
-                    validation.set_summary(
-                        StudioValidationMessage(
-                            StudioValidationMessage.WARNING,
-                            _(u'This component is out of date. The library has new content.'),
-                            action_class='library-update-btn',  # TODO: change this to action_runtime_event='...' once the unit page supports that feature.
-                            action_label=_(u"↻ Update now")
-                        )
-                    )
-                    break
-            else:
-                validation.set_summary(
-                    StudioValidationMessage(
-                        StudioValidationMessage.ERROR,
-                        _(u'Library is invalid, corrupt, or has been deleted.'),
-                        action_class='edit-button',
-                        action_label=_(u"Edit Library List")
-                    )
-                )
+            if not self._validate_library_version(validation, lib_tools, version, library_key):
                 break
 
+            library = lib_tools.get_library(library_key)
+            children_matching_filter = lib_tools.get_filtered_children(library, self.capa_type)
+            # get_filtered_children returns generator, so we're basically checking if there are at least one child
+            # that satisfy filtering. Children are never equal to None, so None is returned only if generator was empty
+            has_children_matching_filter |= next(children_matching_filter, None) is not None
+
+        if not has_children_matching_filter and validation.empty:
+            validation.set_summary(
+                StudioValidationMessage(
+                    StudioValidationMessage.WARNING,
+                    _(u'There are no content matching configured filters in the selected libraries.'),
+                    action_class='edit-button',
+                    action_label=_(u"Edit Library List")
+                )
+            )
+
         return validation
 
     def editor_saved(self, user, old_metadata, old_content):

common/lib/xmodule/xmodule/library_tools.py

@@ -18,7 +18,7 @@ class LibraryToolsService(object):
     def __init__(self, modulestore):
         self.store = modulestore
 
-    def _get_library(self, library_key):
+    def get_library(self, library_key):
         """
         Given a library key like "library-v1:ProblemX+PR0B", return the
         'library' XBlock with meta-information about the library.
@@ -39,24 +39,39 @@ class LibraryToolsService(object):
         Get the version (an ObjectID) of the given library.
         Returns None if the library does not exist.
         """
-        library = self._get_library(lib_key)
+        library = self.get_library(lib_key)
         if library:
             # We need to know the library's version so ensure it's set in library.location.library_key.version_guid
             assert library.location.library_key.version_guid is not None
             return library.location.library_key.version_guid
         return None
 
-    def _filter_child(self, dest_block, child_descriptor):
+    def _filter_child(self, capa_type, child_descriptor):
         """
         Filters children by CAPA problem type, if configured
         """
-        if dest_block.capa_type == ANY_CAPA_TYPE_VALUE:
+        if capa_type == ANY_CAPA_TYPE_VALUE:
             return True
 
         if not isinstance(child_descriptor, CapaDescriptor):
             return False
 
-        return dest_block.capa_type in child_descriptor.problem_types
+        return capa_type in child_descriptor.problem_types
+
+    def get_filtered_children(self, from_block, capa_type=ANY_CAPA_TYPE_VALUE):
+        """
+        Filters children of `from_block` that satisfy filter criteria
+        Returns generator containing (child_key, child) for all children matching filter criteria
+        """
+        children = (
+            (child_key, self.store.get_item(child_key, depth=9))
+            for child_key in from_block.children
+        )
+        return (
+            (child_key, child)
+            for child_key, child in children
+            if self._filter_child(capa_type, child)
+        )
 
     def update_children(self, dest_block, user_id, user_perms=None, update_db=True):
         """
@@ -89,7 +104,7 @@ class LibraryToolsService(object):
             # First, load and validate the source_libraries:
             libraries = []
             for library_key, old_version in dest_block.source_libraries:  # pylint: disable=unused-variable
-                library = self._get_library(library_key)
+                library = self.get_library(library_key)
                 if library is None:
                     raise ValueError("Required library not found.")
                 if user_perms and not user_perms.can_read(library_key):
@@ -109,11 +124,9 @@ class LibraryToolsService(object):
                     Internal method to copy blocks from the library recursively
                     """
                     new_children = []
-                    for child_key in from_block.children:
-                        child = self.store.get_item(child_key, depth=9)
-
-                        if filter_problem_type and not self._filter_child(dest_block, child):
-                            continue
+                    target_capa_type = dest_block.capa_type if filter_problem_type else ANY_CAPA_TYPE_VALUE
+                    filtered_children = self.get_filtered_children(from_block, target_capa_type)
+                    for child_key, child in filtered_children:
                         # We compute a block_id for each matching child block found in the library.
                         # block_ids are unique within any branch, but are not unique per-course or globally.
                         # We need our block_ids to be consistent when content in the library is updated, so