def add_definitions_children(usage_key, def_key):
"""
Recursively add any children of the given XBlock usage+definition to
usages_found.
"""
if not does_block_type_support_children(def_key.block_type):
return
try:
xml_node = xml_for_definition(def_key)
except: # pylint:disable=bare-except
log.exception("Unable to load definition {}".format(def_key))
return
for child in xml_node:
if child.tag != 'xblock-include':
continue
try:
parsed_include = parse_xblock_include(child)
child_usage = usage_for_child_include(
usage_key, def_key, parsed_include)
child_def_key = definition_for_include(
parsed_include, def_key)
except BundleFormatException:
log.exception(
"Unable to parse a child of {}".format(def_key))
continue
usages_found[child_usage] = child_def_key
add_definitions_children(child_usage, child_def_key)
def get_block_display_name(block_or_key):
"""
Efficiently get the display name of the specified block. This is done in a
way that avoids having to load and parse the block's entire XML field data
using its parse_xml() method, which may be very expensive (e.g. the video
XBlock parse_xml leads to various slow edxval API calls in some cases).
This method also defines and implements various fallback mechanisms in case
the ID can't be loaded.
block_or_key can be an XBlock instance, a usage key or a definition key.
Returns the display name as a string
"""
def_key = resolve_definition(block_or_key)
use_draft = get_xblock_app_config().get_learning_context_params().get('use_draft')
cache = BundleCache(def_key.bundle_uuid, draft_name=use_draft)
cache_key = ('block_display_name', str(def_key))
display_name = cache.get(cache_key)
if display_name is None:
# Instead of loading the block, just load its XML and parse it
try:
olx_node = xml_for_definition(def_key)
except Exception: # pylint: disable=broad-except
log.exception("Error when trying to get display_name for block definition %s", def_key)
# Return now so we don't cache the error result
return xblock_type_display_name(def_key.block_type)
try:
display_name = olx_node.attrib['display_name']
except KeyError:
display_name = xblock_type_display_name(def_key.block_type)
cache.set(cache_key, display_name)
return display_name