So it appears the Dygraphs script isn’t taking into account the local time zone/DST of the user when it’s creating the graph, it’s just using the UTC date provided by the Python script in the JSON file. There is an option in Dygraphs to use the localtime zone, but the formatting of the date will need a custom filter.
Is there any plans to do so, if not would you accept a pull request to possibly add in the functionality? Also, it would be nice to get a 12 hour format on the graph, and/or an option to toggle the setting in the maintenance panel.
I experienced the time zone issue until I went into the BrewPi SSH session and performed “sudo raspi-config”. Choose option “#4 Internationalisation Options” and then choose your local time zone. I believe this required a reboot but afterwards the BrewPi chart showed local time.
I think it would indeed be a better design to log the data in a universal format and only display it adapted for the timezone.
That way, if you change the timezone on your pi, you are not creating jumps or overlap in the chart. Of course the time on the pi should still be set correctly.
I’ll happily take a pull request to increase immunity to time/timezone errors. Please base any pull request on the develop branch.