UI panel directly from any known backend

I wonder if could be possible to add an instrument panel that shows actual values directly from let’s say Prometheus backend, without use of database. Some meters do usually send actual data through a bakckend that is then used by a database to store data. Grafana is able to retrieve data from a database, but why is not possible also to display the actual measurements with help of intercepting data from a backend?

You could write a small webpage that does that and use https://grafana.com/grafana/plugins/ryantxu-ajax-panel to display it.