Fix: Plotly Chart Deprecation Warning With Width

Understanding the st.plotly_chart Deprecation Warning

Hey guys! Let's dive into a common hiccup when using st.plotly_chart in Streamlit. You might have bumped into a deprecation warning about kwargs, even when you're just trying to use the documented parameters like width. This can be super frustrating, but don't worry, we'll break it down and find a solution. The core issue revolves around how Streamlit handles keyword arguments (kwargs) within the st.plotly_chart function, particularly when you're specifying the width or height of the chart. The warning pops up because Streamlit's underlying implementation has flagged the use of variable keyword arguments as deprecated. This means that in future releases, these kwargs might be removed entirely. Our goal is to ensure your code runs smoothly without triggering this warning and to align with the best practices recommended by the Streamlit team.

To give you a better grasp of the situation, let's consider the initial problem and the environment it's occurring in. Initially, the user is receiving the warning while using the documented parameters without passing any variable keyword arguments. This is a regression, meaning this used to work in older versions of the library. It is important to reproduce the issue to verify the root cause. This information is a starting point for us to understand the scope and the extent of the impact of the problem. This can include looking at the version of the streamlit library, the version of python, the operating system, the browser being used, and other relevant information.

Reproducing the Issue: Code Example

To understand the issue better, let's look at a straightforward code snippet that triggers this warning. Here's a concise example:

import plotly.graph_objects as go
import streamlit as st

fig = go.Figure()
fig.add_trace(go.Barpolar(r=[1], theta=[0], width=[120]))
fig.update_layout(width=500, height=360)

st.plotly_chart(fig, width="content")

In this code, we're creating a simple polar bar chart using Plotly, setting its dimensions, and then displaying it in Streamlit with st.plotly_chart. The width="content" part is where the trouble begins. Even though we are not passing any additional, unspecified keyword arguments, the deprecation warning appears. This behavior can be unexpected, especially when you are following the official Streamlit documentation. The deprecation warning is intended to inform you about the future removal of variable keyword arguments, urging you to use the config argument instead to configure Plotly options. However, as demonstrated in this scenario, the warning is also displayed when you use width or height, which are perfectly valid parameters. In the following sections, we will explore the underlying reason for this behavior and potential solutions to avoid the warning.

Troubleshooting the Deprecation Warning

Alright, let's get our hands dirty and figure out why this deprecation warning is showing up and, more importantly, how to fix it. The core of the problem likely stems from how st.plotly_chart internally handles the width and height parameters, or perhaps a conflict within the function's argument parsing. The warning message suggests using the config argument for Plotly configuration options. However, the original code, as shown earlier, does not involve Plotly configuration options; instead, it's about the dimensions of the chart. Therefore, applying the recommended solution in the warning is not appropriate in this situation. It is essential to understand the inner workings of the st.plotly_chart function to find a proper solution and prevent the warning from displaying.

One approach is to examine the source code of the st.plotly_chart function to see how it processes the width and height arguments. This is easier said than done, but it's the best way to determine if there's an unnecessary use of kwargs internally. Another possible solution involves updating Streamlit and Plotly versions to the latest releases. Sometimes, library maintainers release fixes that address these types of issues. By updating, we ensure that you are using the latest bug fixes and improvements. If updating doesn't resolve the issue, you might consider alternative ways to specify the width and height, such as using the layout argument of fig.update_layout in Plotly, and see if this affects the warning.

Investigating the Source Code

If you're up for it, diving into the source code can be enlightening. You can find the source code for st.plotly_chart within the Streamlit library itself. Look for where the function parses the arguments and handles the width and height parameters. This will tell you if the function is inadvertently passing the width and height as kwargs. Another option is to debug the function with a debugger to check what's happening at runtime. When you inspect the source code, focus on how width and height are being processed. Look for any instances where these parameters are being passed to a function that accepts kwargs. If there's an unnecessary use of kwargs, this could explain the warning. Modifying the source code may be necessary, but only if you have a thorough understanding of the Streamlit library.

Updating Streamlit and Plotly

Keeping your libraries updated is always a good practice. Run pip install --upgrade streamlit plotly in your terminal. This will ensure you are using the most recent versions of Streamlit and Plotly. After upgrading, rerun your code example to see if the warning is still present. If the warning persists, it indicates that the issue may not have been addressed in the latest updates, and you may need to consider alternative solutions.

Alternative Approaches to Setting Width and Height

As a workaround, try using Plotly's update_layout to set the width and height. For example:

import plotly.graph_objects as go
import streamlit as st

fig = go.Figure()
fig.add_trace(go.Barpolar(r=[1], theta=[0], width=[120]))
fig.update_layout(width=500, height=360)

st.plotly_chart(fig)

By setting the dimensions within Plotly's layout, you avoid passing them directly to st.plotly_chart, which might circumvent the warning. If this works, it suggests that the warning is specific to how st.plotly_chart handles the width and height parameters directly. This workaround may not be ideal, but it's a way to ensure your app works without the deprecation warning.

Conclusion: Navigating the Deprecation Warning

So, what's the deal? The st.plotly_chart deprecation warning is a bit of a head-scratcher when it comes to the width and height parameters. Ideally, using width and height should not trigger a warning since they are part of the documented parameters. However, in the current implementation, it seems like there is an internal conflict. The strategies we've discussed – examining the source code, updating libraries, and exploring alternative methods – should give you a better handle on the situation and help you keep your Streamlit apps running smoothly. Remember, the best approach depends on your specific needs, but knowing what's going on under the hood can save you a lot of headaches down the line. Keep coding, keep experimenting, and don't let those deprecation warnings get you down! By understanding the underlying issue and by using these troubleshooting techniques, you'll be well-equipped to handle similar warnings in the future.