Query rancher-metadata by label, and return the first, or all of the values as a single value, csv, or a list.
Usage:
roundup [options] {hosts|stacks|services|containers} predicate value-name
Example: Fetch first container name that has the label "arangodb_cluster_name" with the value "cluster1":
roundup -first containers arangodb_cluster_name=cluster1 name
Options:
-csv Return as comma separated values
-first Select first entry only
-hostname The hostname for the rancher metadata service (defaults to rancher-metadata)