Domoticz

Using the API and a request such as you can get raw data for a temperature plot. Is there a way to export an actual graphics file (like a .svg or a .png) rather than raw data from the API? The UI does it when you click on the hamburger menu while viewing a plot so I'd suspect it can be done from the /json.htm interface too...

I believe this has been asked before. As I remember:
As it is the client (your browser) that creates the PNG wile exporting it with the hamburger menu entry it seems not possible to execute this from a server API. It will need an Highcharts server to do this.