Adding callbacks flags for additional figure on Datashader Dashboard

Question

I am attempting to add additional figures to the datashader dashboard example based on alternative aggregates. For an example, along with the geographic NYC_Taxi lat, lon PU and DO aggregates, I would like to include a second panel that has the trip distance/tip figures within the same dashboard.

I have the second figure set up in the layout and I can mirror the datashader layer from the first image. Dasbboard with two mirrored images

I really think I need a flag sent through the

ds_args = {
'width': fields.Int(missing=800),
'height': fields.Int(missing=600),
'select': fields.Str(missing=""),
'name': fields.Str(missing='fig1'),
}

along with the addition of a name field in the service url for each image.

self.service_url = 'http://{host}:{port}/datashader?'
self.service_url += 'height={HEIGHT}&'
self.service_url += 'width={WIDTH}&'
self.service_url += 'select={XMIN},{YMIN},{XMAX},{YMAX}&'
self.service_url += 'name={NAME}&'
self.service_url += 'cachebust={cachebust}'

with the name field being the flag for creating the proper aggregate. I have come to understand that the service_url contains the appropriate fields for the URL request, but I don't understand how to give a figure a name or a specific tag and pass is back to the class GetDataset() so that I can start picking and choosing from a hypothetical self.models.specific_figure.featurelist for aggregate creation.

Answer 1

A temporary hack I've found is to hard code self.service_url += 'name={NAME}&' to a unique figure name based on a service_url for each desired figure as well as adding the image_renderer.image_source = ImageSource() for each image to udpate_image() as well as inline within the AppView() class after initial figure creation.

The name parameter is successfully passed in based on the addition of 'name': fields.Str(), to ds_args and then it becomes a matter of selecting the proper aggregate methods based on the name and current selections for that figure.