/st.experimental_get_query_params

Primary LanguagePython

st.experimental_get_query_params

st.experimental_get_query_params allows the retrieval of query parameters directly from the URL of the user's browser.

Demo app

  1. The following link loads the demo app with no query parameters (notice the error message):

Streamlit App

  1. The following link loads the demo app with query parameters (no error message here):

Streamlit App

Code

Here's how to use st.experimental_get_query_params:

import streamlit as st

st.title('st.experimental_get_query_params')

with st.expander('About this app'):
  st.write("`st.experimental_get_query_params` allows the retrieval of query parameters directly from the URL of the user's browser.")

# 1. Instructions
st.header('1. Instructions')
st.markdown('''
In the above URL bar of your internet browser, append the following:
`?name=Jack&surname=Beanstalk`
after the base URL `http://share.streamlit.io/dataprofessor/st.experimental_get_query_params/`
such that it becomes 
`http://share.streamlit.io/dataprofessor/st.experimental_get_query_params/?firstname=Jack&surname=Beanstalk`
''')


# 2. Contents of st.experimental_get_query_params
st.header('2. Contents of st.experimental_get_query_params')
st.write(st.experimental_get_query_params())


# 3. Retrieving and displaying information from the URL
st.header('3. Retrieving and displaying information from the URL')

firstname = st.experimental_get_query_params()['firstname'][0]
surname = st.experimental_get_query_params()['surname'][0]

st.write(f'Hello **{firstname} {surname}**, how are you?')

Line-by-line explanation

The very first thing to do when creating a Streamlit app is to start by importing the streamlit library as st like so:

import streamlit as st

Next, we'll give the app a title:

st.title('st.experimental_get_query_params')

Let's also add an About drop-down box:

with st.expander('About this app'):
  st.write("`st.experimental_get_query_params` allows the retrieval of query parameters directly from the URL of the user's browser.")

Then, we'll provide instructions to visitors of the app on how they can pass query parameters directly to the URL:

# 1. Instructions
st.header('1. Instructions')
st.markdown('''
In the above URL bar of your internet browser, append the following:
`?name=Jack&surname=Beanstalk`
after the base URL `http://share.streamlit.io/dataprofessor/st.experimental_get_query_params/`
such that it becomes 
`http://share.streamlit.io/dataprofessor/st.experimental_get_query_params/?firstname=Jack&surname=Beanstalk`
''')

Subsequently, we'll display the contents of the st.experimental_get_query_params command.

# 2. Contents of st.experimental_get_query_params
st.header('2. Contents of st.experimental_get_query_params')
st.write(st.experimental_get_query_params())

Finally, we'll select and display selective information from the URL's query parameter:

# 3. Retrieving and displaying information from the URL
st.header('3. Retrieving and displaying information from the URL')

firstname = st.experimental_get_query_params()['firstname'][0]
surname = st.experimental_get_query_params()['surname'][0]

st.write(f'Hello **{firstname} {surname}**, how are you?')

Further reading