Template variable using lable_join

I am trying to create a template variable from a Prometheus data source using label_join function like

label_values(label_join(app:healthcheck:gauge{application=“collectHealthies”}, “full_name”, " ", “first_name”, “last_name”) ,full_name)

but I am getting

Template variables could not be initialized: parse error at char 11: could not parse remaining input “(app:healthchec”…

https://prometheus.io/docs/prometheus/latest/querying/functions/#label_join

1 Like

i meet the same trouble!

Same issue. The goal is to aggregate multiple label names into single one and pass them to a variable. Does anyone know how to achieve this?

I just hit this problem too and solved it, sharing the solution to my specific use case might help others:

The query uses query_result():

query_result(
  max  by (nodepool) (
    label_join(
      kube_node_labels{cluster=~"$cluster"}
      , "nodepool", "", "label_cloud_google_com_gke_nodepool", "label_agentpool")
  )
)

This results in values like {nodepool="some-node-pool"} 1 1623140151000

To solve this, add a regex to grab the right value:

/nodepool="(.*)".*/