Added ability to disable xblock types in LMS.

TNL-2305

common/lib/xmodule/xmodule/hidden_module.py

@@ -3,6 +3,9 @@ from xmodule.raw_module import RawDescriptor
 
 
 class HiddenModule(XModule):
+
+    HIDDEN = True
+
     def get_html(self):
         if self.system.user_is_staff:
             return u"ERROR: This module is unknown--students will not see it at all"

common/lib/xmodule/xmodule/modulestore/__init__.py

@@ -1122,7 +1122,7 @@ class ModuleStoreReadBase(BulkOperationsMixin, ModuleStoreRead):
         contentstore=None,
         doc_store_config=None,  # ignore if passed up
         metadata_inheritance_cache_subsystem=None, request_cache=None,
-        xblock_mixins=(), xblock_select=None,
+        xblock_mixins=(), xblock_select=None, disabled_xblock_types=(),  # pylint: disable=bad-continuation
         # temporary parms to enable backward compatibility. remove once all envs migrated
         db=None, collection=None, host=None, port=None, tz_aware=True, user=None, password=None,
         # allow lower level init args to pass harmlessly
@@ -1139,6 +1139,7 @@ class ModuleStoreReadBase(BulkOperationsMixin, ModuleStoreRead):
         self.request_cache = request_cache
         self.xblock_mixins = xblock_mixins
         self.xblock_select = xblock_select
+        self.disabled_xblock_types = disabled_xblock_types
         self.contentstore = contentstore
 
     def get_course_errors(self, course_key):

common/lib/xmodule/xmodule/modulestore/django.py

@@ -46,6 +46,11 @@ try:
 except ImportError:
     HAS_USER_SERVICE = False
 
+try:
+    from xblock_django.models import XBlockDisableConfig
+except ImportError:
+    XBlockDisableConfig = None
+
 log = logging.getLogger(__name__)
 ASSET_IGNORE_REGEX = getattr(settings, "ASSET_IGNORE_REGEX", r"(^\._.*$)|(^\.DS_Store$)|(^.*~$)")
 
@@ -161,12 +166,18 @@ def create_modulestore_instance(
     if 'read_preference' in doc_store_config:
         doc_store_config['read_preference'] = getattr(ReadPreference, doc_store_config['read_preference'])
 
+    if XBlockDisableConfig and settings.FEATURES.get('ENABLE_DISABLING_XBLOCK_TYPES', False):
+        disabled_xblock_types = XBlockDisableConfig.disabled_block_types()
+    else:
+        disabled_xblock_types = ()
+
     return class_(
         contentstore=content_store,
         metadata_inheritance_cache_subsystem=metadata_inheritance_cache,
         request_cache=request_cache,
         xblock_mixins=getattr(settings, 'XBLOCK_MIXINS', ()),
         xblock_select=getattr(settings, 'XBLOCK_SELECT_FUNCTION', None),
+        disabled_xblock_types=disabled_xblock_types,
         doc_store_config=doc_store_config,
         i18n_service=i18n_service or ModuleI18nService(),
         fs_service=fs_service or xblock.reference.plugins.FSService(),

common/lib/xmodule/xmodule/modulestore/mongo/base.py

@@ -937,6 +937,7 @@ class MongoModuleStore(ModuleStoreDraftAndPublished, ModuleStoreWriteBase, Mongo
                 cached_metadata=cached_metadata,
                 mixins=self.xblock_mixins,
                 select=self.xblock_select,
+                disabled_xblock_types=self.disabled_xblock_types,
                 services=services,
             )
         else:

common/lib/xmodule/xmodule/modulestore/split_mongo/split.py

@@ -3099,6 +3099,7 @@ class SplitMongoModuleStore(SplitBulkWriteMixin, ModuleStoreWriteBase):
             render_template=self.render_template,
             mixins=self.xblock_mixins,
             select=self.xblock_select,
+            disabled_xblock_types=self.disabled_xblock_types,
             services=self.services,
         )
 

common/lib/xmodule/xmodule/x_module.py

@@ -1298,9 +1298,9 @@ class DescriptorSystem(MetricsMixin, ConfigurableFragmentWrapper, Runtime):  # p
     """
     Base class for :class:`Runtime`s to be used with :class:`XModuleDescriptor`s
     """
-
+    # pylint: disable=bad-continuation
     def __init__(
-        self, load_item, resources_fs, error_tracker, get_policy=None, **kwargs
+        self, load_item, resources_fs, error_tracker, get_policy=None, disabled_xblock_types=(), **kwargs
     ):
         """
         load_item: Takes a Location and returns an XModuleDescriptor
@@ -1358,10 +1358,20 @@ class DescriptorSystem(MetricsMixin, ConfigurableFragmentWrapper, Runtime):  # p
         else:
             self.get_policy = lambda u: {}
 
+        self.disabled_xblock_types = disabled_xblock_types
+
     def get_block(self, usage_id, for_parent=None):
         """See documentation for `xblock.runtime:Runtime.get_block`"""
         return self.load_item(usage_id, for_parent=for_parent)
 
+    def load_block_type(self, block_type):
+        """
+        Returns a subclass of :class:`.XBlock` that corresponds to the specified `block_type`.
+        """
+        if block_type in self.disabled_xblock_types:
+            return self.default_class
+        return super(DescriptorSystem, self).load_block_type(block_type)
+
     def get_field_provenance(self, xblock, field):
         """
         For the given xblock, return a dict for the field's current state: