CODEWITHSUNDEEP
pythonplotlypngstreamlit
user29633435
user29633435

Reputation: 1

Plotly graph object not exporting as png in Streamlit app

I am trying to export my plotly graph object to a png in my Streamlit app, I am running my Streamlit app locally using: python -m streamlit run Streamlit_Mapping.py The code I am referring to looks like this:

import plotly.graph_objects as go
import plotly.io as pio
import streamlit as st

def main():
    fig = go.Figure(data=go.Scatter(x=[1, 2, 3], y=[3, 2, 1], mode='markers'))

    filename = 'image.png'

    with st.spinner('exporting image'):
        try:
            pio.write_image(fig, filename, format="png", engine="kaleido")
            print("Image export successful.")
        except Exception as e:
            print(f"Image export failed: {e}")

    with open(filename, "rb") as file:
        st.download_button(
            label="Download Plot as PNG",
            data=file,
            file_name=filename,
            mime="image/png"
        )

if __name__ == '__main__':
    main()

My app gets stuck in the write_image function. When I run the code below which is not part of a streamlit app, it runs perfectly fine.

import plotly.graph_objects as go
from plotly.io import to_image

# Test Plotly GO image export locally
fig = go.Figure(data=go.Scatter(x=[1, 2, 3], y=[3, 2, 1], mode='markers'))
try:
    img = to_image(fig, format="png")
    print("Image export successful.")
except Exception as e:
    print(f"Image export failed: {e}")

I have tried python 3.11 and 3.9 with plotly 6.0.0, kaleido 0.4.1 and plotly 5.5.0 and kaleido 0.2.1 respectivley

I have tried the fix here: Saving a plotly image not working with kaleido even though it is installed

And the fix here: https://github.com/plotly/Kaleido/issues/61

Without any luck...

Does anyone know how to tackle this issue?

Upvotes: 0

Views: 52

Answers (1)

Diego Torres Milano
Diego Torres Milano

Reputation: 69388

I can't see any issue with your code, but if you think write_image might be taking longer than expected, you can add some timeout

#! /usr/bin/env streamlit run
import plotly.graph_objects as go
import plotly.io as pio
import streamlit as st
import asyncio

async def write_image(pio, fig, filename):
    pio.write_image(fig, filename, format="png", engine="kaleido")

async def main():
    fig = go.Figure(data=go.Scatter(x=[1, 2, 3], y=[3, 2, 1], mode='markers'))

    filename = 'image.png'

    with st.spinner('exporting image'):
        try:
            await asyncio.wait_for(write_image(pio, fig, filename), timeout=15)
            st.success("Image export successful.")
        except asyncio.TimeoutError:
            st.error(f"Timed out")
        except Exception as e:
            st.error(f"Image export failed: {e}")

    with open(filename, "rb") as file:
        st.image(filename)
        st.download_button(
            label="Download Plot as PNG",
            data=file,
            file_name=filename,
            mime="image/png"
        )

if __name__ == '__main__':
    asyncio.run(main())

Upvotes: 0

Related Questions