Streamlit apps

Environment requirements

Your conda environment (used in JHub Apps Launcher's App creation form) must have the following packages for successful app deployment:

• jhsingle-native-proxy >= 0.8.2
• streamlit
• altair
• Other libraries used in the app

note

In some cases, you may need ipywidgets

Example application

To deploy the Streamlit App using JHub Apps, you can use the following code and environment:

Code (Python file)

In a Python file, copy the following lines of code.

streamlit_app.py

from collections import namedtuple
import altair as alt
import math
import pandas as pd
import streamlit as st

"""
# Welcome to Streamlit!

"""

total_points = st.slider("Number of points in spiral", 1, 5000, 2000)
num_turns = st.slider("Number of turns in spiral", 1, 100, 9)

Point = namedtuple("Point", "x y")
data = []

points_per_turn = total_points / num_turns

for curr_point_num in range(total_points):
    curr_turn, i = divmod(curr_point_num, points_per_turn)
    angle = (curr_turn + 1) * 2 * math.pi * i / points_per_turn
    radius = curr_point_num / total_points
    x = radius * math.cos(angle)
    y = radius * math.sin(angle)
    data.append(Point(x, y))

st.altair_chart(
    alt.Chart(pd.DataFrame(data), height=500, width=500)
    .mark_circle(color="#0068c9", opacity=0.5)
    .encode(x="x:Q", y="y:Q")
)

You will see an app that displays a spiral of points:

Environment specification

Use the following spec to create a Conda environment wherever JHub Apps is deployed. If using Nebari, use this spec to create an environment with conda-store.

channels:
  - conda-forge
dependencies:
  - altair
  - jhsingle-native-proxy>=0.8.2
  - pandas
  - streamlit
  - ipykernel

Next steps

✨ Launch app →