Default Chart Refresh

According to this guide


a chart may be displayed in the browser by calling a specific URL.

The example given in the link above is

http://localhost:8080/chart?groups=Heizung&period=W&random=1&h=800&w=1200

Questions:

  1. The parameter random is not explained. What does is do?
  2. I’ve tried adding a parameter refresh to the URL but this doesn’t seem to do anything:
http://localhost:8080/chart?groups=Heizung&period=W&refresh=1000&h=800&w=1200

Is there a way to provide a URL that refreshes the chart automatically?

For my tests I’m currently using openHAB 1.8.3.