I requested candidate sets for Mr_Monkey with:

docker exec -it listenbrainz-cron-prod python3 manage.py spark request_candidate_sets --top=40 --similar=15 --html --days=14 --user-name=Mr_Monkey

And it broke the request_consumer – do user names need to have correct case? In any case (ha!) an empty candidate set causes a crash:

[2020-07-27 09:26:14,591] INFO in candidate_sets: Fetching listens to get top artists...
[2020-07-27 09:26:14,622] INFO in candidate_sets: Fetching top artists...
[2020-07-27 09:26:14,675] INFO in candidate_sets: Preparing top artists candidate set...
[2020-07-27 09:26:14,701] INFO in candidate_sets: Fetching similar artists...
[2020-07-27 09:26:14,758] INFO in candidate_sets: Preparing similar artists candidate set...
[2020-07-27 09:26:14,781] INFO in candidate_sets: Saving candidate sets...
[2020-07-27 09:26:15,687] ERROR in candidate_sets: Cannot save empty top artist candidate set
Traceback (most recent call last):
File "/rec/listenbrainz_spark/recommendations/candidate_sets.py", line 297, in save_candidate_sets
top_artist_candidate_set_df.take(1)[0]
IndexError: list index out of range
Sentry is attempting to send 1 pending error messages
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