def get_all_asset_metadata(self, course_key, asset_type, start=0, maxresults=-1, sort=None, **kwargs):
"""
Returns a list of asset metadata for all assets of the given asset_type in the course.
Args:
course_key (CourseKey): course identifier
asset_type (str): the block_type of the assets to return
start (int): optional - start at this asset number. Zero-based!
maxresults (int): optional - return at most this many, -1 means no limit
sort (array): optional - None means no sort
(sort_by (str), sort_order (str))
sort_by - one of 'uploadDate' or 'displayname'
sort_order - one of SortOrder.ascending or SortOrder.descending
Returns:
List of AssetMetadata objects.
"""
course_assets = self._find_course_assets(course_key)
if course_assets is None:
# If no course assets are found, return None instead of empty list
# to distinguish zero assets from "not able to retrieve assets".
return None
# Determine the proper sort - with defaults of ('displayname', SortOrder.ascending).
sort_field = 'filename'
sort_order = ModuleStoreEnum.SortOrder.ascending
if sort:
if sort[0] == 'uploadDate':
sort_field = 'edited_on'
if sort[1] == ModuleStoreEnum.SortOrder.descending:
sort_order = ModuleStoreEnum.SortOrder.descending
all_assets = SortedListWithKey(course_assets.get(asset_type, []), key=itemgetter(sort_field))
num_assets = len(all_assets)
start_idx = start
end_idx = min(num_assets, start + maxresults)
if maxresults < 0:
# No limit on the results.
end_idx = num_assets
step_incr = 1
if sort_order == ModuleStoreEnum.SortOrder.descending:
# Flip the indices and iterate backwards.
step_incr = -1
start_idx = (num_assets - 1) - start_idx
end_idx = (num_assets - 1) - end_idx
ret_assets = []
for idx in xrange(start_idx, end_idx, step_incr):
raw_asset = all_assets[idx]
new_asset = AssetMetadata(course_key.make_asset_key(asset_type, raw_asset['filename']))
new_asset.from_mongo(raw_asset)
ret_assets.append(new_asset)
return ret_assets
def find_asset_metadata(self, asset_key, **kwargs):
"""
Find the metadata for a particular course asset.
Arguments:
asset_key (AssetKey): key containing original asset filename
Returns:
asset metadata (AssetMetadata) -or- None if not found
"""
course_assets, asset_idx = self._find_course_asset(asset_key)
if asset_idx is None:
return None
info = asset_key.block_type
mdata = AssetMetadata(asset_key, asset_key.path, **kwargs)
all_assets = course_assets[info]
mdata.from_mongo(all_assets[asset_idx])
return mdata
