def get_featured_comments_for_assets(asset_ids, no_of_comments=1):
# Calculate the ranked comments per asset as a separate "table".
CommentAlias = Comment.alias()
subquery = CommentAlias.select(
CommentAlias.id,
fn.RANK().over(partition_by=[CommentAlias.asset],
order_by=[
CommentAlias.editors_pick.desc(),
CommentAlias.parent.asc(),
CommentAlias.created.desc()
]).alias('rnk')).where(
CommentAlias.asset_id << asset_ids).alias('subq')
comments = Comment.select(Comment).join(Asset).where(
Comment.asset_id << asset_ids).switch(Comment).join(
subquery,
on=((subquery.c.id == Comment.id) &
(subquery.c.rnk <= no_of_comments))).execute()
asset2comments = {}
for comment in comments:
if comment.asset_id not in asset2comments:
asset2comments[comment.asset_id] = []
asset2comments[comment.asset_id].append(comment.to_dict())
return asset2comments
