Question about changing query parameters (st 1.30)

[kharlamarla]

Hi all!

I encountered a problem after updating streamlit 1.30. The problem concerns a new (changed) function - query_params https://docs.streamlit.io/library/api-reference/utilities/st.query_params .

Previously, when using the experimental version, the specified query parameters were saved and could be used on other pages. Now, after setting a query parameter on one page, it is reset when moving to another.

Tell me, is this a feature of the implementation or is it a bug? Thx.

Win10, Py 3.11.7, Streamlit 1.30 locally.

[Caroline]

Hey @kharlamarla,

Thanks for flagging this issue! Is your app using st.rerun? Query parameters are expected to persist across pages, but there is currently a confirmed bug with st.query_params when used in conjunction with st.rerun (GitHub Issue here)

[kharlamarla]

Thanks for your reply. Yes, my code uses st.rerun, but in the logic of displaying two pages (when switching between them) this function is not called.

[kharlamarla]

I wrote code for demonstration that does not use st.rerun and shows the essence of the error. I also attached a video. Please have a look.

GitHub - kharlamarla/st_1.31-query-params-demo

[Caroline]

Thanks so much for sharing that example! I’ve investigated this further and this is actually intended behavior to simulate the same behavior of regular webpages.

Here are a few related GitHub Issues that explain the decision to make this change in more detail: #6725, #5505, #7982

[kharlamarla]

Thanks for providing details of the changes to this approach. It would probably be great to show this information in the documentation so that it is explicit.

Thanks a lot.

[mathcatsand]

I’ll look into making the note more visible. It’s currently the last sentence before the “Repeated keys” section on the st.query_params page. Since it’s just one line, it’s definitely easy to miss. Thanks for highlighting.