In all preprocessing steps possible, it seems not to be possible to use built-in macros as part of the options. Tested with both JSONPATH and Prometheus query.

My use case is a prometheus exporter which gives back a quite big number of metrics with a label of every IP address or host name, containing some meta information on the host in other labels. With a HTTP item, I want to gather this information and pull out the meta information for the current host. For this, I would like to use {HOST.CONN} built-in macro. Unfortunately, this doesn't seem to be possible.