Sum values by day in time series

I have searched around google but can’t find a solution.
I’m fetching data from my own JSON data source. And I could aggregate data by days in there, but I would like to figure out how to do this on the panel side.
It probably is some sort of transformation, but reading the guide I can’t really figure it out.

So I would like to see just 1 bar per day with total sum of all data points during that period.