Comment 5 for bug 1982712

Another issue:

I found there are some similar charms like:

https://launchpad.net/charm-prometheus-grok-exporter
https://launchpad.net/charm-prometheus-blackbox-exporter

They implement exporter as a charm and relation to workload && prometheus.
I think this way of design is more flexible than install in the mysql.

We should implement another charm for prometheus mysql exporter with juju operator framework.
Relation the charm as subordinate to each mysql node in mysql innodb cluster

But later we will need to discuss how to give user & password to the exporter charm.