Using lonboard in a Databricks notebook

[jpd-defra]

Hello,

Thanks for sharing lonboard, I'm very excited at the prospect of using it.

I currently use Databricks for my python work. I have tried producing an interactive map with the following:

While the execution doesn't fail, the widget/map doesn't display. I've read that people have got round similar issues with folium by exporting to html then displaying. Has anyone got an idea how I could do this with lonboard please?

Note: My cluster is a above the minimum runtime version suggested, and I have tried running multiple times.

[kylebarron]

Per their docs, some custom widgets are supported, but IIRC Databricks doesn't support the full Jupyter Widgets protocol. You can look in your browser console to see if there's any errors, and you might want to try rendering a map with an empty/very small dataset to make sure it's not related to the size of your data. I don't have access to a Databricks instance, and so I don't have a way to test on Databricks.

Edit: Actually if I had to guess, the issue is probably with Databricks requiring an older version of JavaScript than what we're using. We're building on top of Anywidget, which makes it 100x easier to build Jupyter Widgets, but compiles to a recent version of JS. We could try transpiling our JS bundle to ES5 but I don't think that would work with anywidget.

#8 is tracking export to HTML, but that's a decent chunk of work and I don't have a timeline suggestion.

[jpd-defra]

Thanks for the swift response Kyle, that's all very helpful insight.

I checked again with one small, simple polygon and the same issue arose so I don't think it was a dataset size issue. Databricks can be very frustrating at times. I'm going to look for a way to utilise a Jupyter notebook for dataviz in my organisation (potentially publishing with Posit Connect). I'll keep an eye out for HTML developments in future though!

Thanks again.

[kylebarron]

Version 0.3 added export to a static HTML file, so that may be compatible with databricks

[jpd-defra]

Thanks for letting me know. I've given it a go, and unfortunately still unsuccessful. Here's my code and output if it's of any interest, but as you say, this is almost certainly a Databricks issue!

from lonboard import SolidPolygonLayer, Map
from geopandas import read_parquet

dat = read_parquet(f'/Workspace/Repos/{username}/sds-15min-greenspace/data/focal_boxes')
layer = SolidPolygonLayer.from_geopandas(dat[['geometry']])
mymap = Map(layers = [layer])
mymap.to_html(f'/dbfs/mnt/lab/unrestricted/{username}/sandbox/lonboard_test.html')

When trying to use displayHTML the map doesn't render and only displays the path:

Trying an alternative with IPython:

Clicking the output to show the error reveals:

[kylebarron]

SyntaxError: Invalid or unexpected token means that databricks requires an older version of JS, because of the way databricks notebooks are set up, which I don't think is feasible for us to try and support.

[jpd-defra]

No problem - I appreciate you letting me know about the html export updates. I have a jupyter notebook alternative plan so hoping I can make use of lonboard for my work.