Databricks app and R shiny

Paddy_chu · ‎04-14-2025

Hello,

I've been testing the Databricks app and have the follow questions:

1. My organization currently uses Catalog Explorer instead of Unity Catalog. I want to develop a Shiny app and was able to run code from the template under New > App. However, this environment doesn't support package installation and doesn't allow conversion of Spark tables from Catalog Explorer to Pandas DataFrames for visualizations. I don't have admin rights to install any packages on the cluster.

Is there a way for the Shiny app to access data from Catalog Explorer?

2. I prefer developing apps on Databricks notebooks, but I haven't been able to run a Shiny app using Python with shiny for python code. Here is the code I've used in my notebook:

from shiny import ui, render, App

app_ui = ui.page_fluid(

ui.input_slider("n", "N", 0, 100, 40),

ui.output_text_verbatim("txt"),

)

def server(input, output, session😞

@render.text

def txt():

return f"n*2 is {input.n() * 2}"

app = App(app_ui, server)

The code executed without errors, but the app did not launch. When I write the code in R, an URL path pops up without any issues. However, after the first time generating the R Shiny app, my notebook always gets stuck with the cell constantly showing as "waiting." Using R for Shiny, I can develop the app on a Databricks notebook with data from Catalog Explorer, but I can't deploy it as easily as deploying it on Databricks App, and Databricks App doesn't seem to support R code.

Does anyone know how to use Shiny for Python to develop Shiny app on a Databricks notebook and how to launch the app on Databricks notebook so I can see the output?

Appreciate for any solutions.

Thanks,