Display snapshot of all values on hover about horizon-timeseries-chart

[vasturiano]

Thanks for reaching out @balaagola.

That is slightly complicated because the different timeseries can have a different time grid for the points. So, if you are hovering on a particular timestamp in a series, doesn't necessarily mean the other timeseries will have a point at that same exact time. This makes it difficult to add a combo tooltip, or a label per series indicating the value at that time.

Having said that, if you know the logic of the distribution of your points, from the consuming application side, you can always use onHover(...) to extract the current timestamp under the mouse pointer, and use it to reach into your data to extract the other series values. You could even go a step further and re-inject those values into the series name using seriesLabelFormatter(...).

[throrin19]

Same need here. Horizon is great to compare easilly lot of series, but if the hover does not show all values as same time, is really useless....