Streamlit local storage

This repo is to help streamlt users manage data in a browser's local storage. Built on the use-local-storage-state that allows for real time updates especially important when local storage item is deleted.

for more details: https://www.npmjs.com/package/use-local-storage-state

pip install streamlit-local-storage

store items to local storage

from streamlit_local_storage import LocalStorage
localS = LocalStorage()

itemKey = "camera"
itemValue = "Tarah"
localS.setItem(itemKey, itemValue)

get item from local storage

itemKey = "Taylor Swift"
local_storage_item = localS.getItem(itemKey)

get all items saved on local storage

saved_individual = localS.getAll()
st.write(saved_individual)

delete all

localS.deleteAll()

when getting local storage items with streamlit widgets

st.subheader("Method 1")

def LocalStorageManager():
    return LocalStorage()
localS = LocalStorageManager()

if "get_val" not in st.session_state:
    st.session_state["get_val"] = None

with st.form("get_data"):
    st.text_input("key", key="get_local_storage_v")
    st.form_submit_button("Submit") 

if st.session_state["get_local_storage_v"] != "":
    val_ = localS.getItem(st.session_state["get_local_storage_v"], key="test_get_item")
    st.session_state["get_val"] = val_
st.write(st.session_state["get_val"])

### When using callbacks for get item, can use the below example. But it wont reveal data unless app has rendered twice. But callback can be work without a hitch generally (based on my tests).

st.subheader("Method 2 - using callback. Does not load instantly especially for get storage")

def LocalStorageManager():
    return LocalStorage()
localS = LocalStorageManager()

if "get_val_2" not in st.session_state:
    st.session_state["get_val_2"] = None

if "st_col_test" not in st.session_state:
    st.session_state["st_col_test"] = None 

def change_state_2():

    with st.session_state["st_col_test"][0]: # call method from below form
        localS.getItem(st.session_state["get_local_storage_v_2"], key="test_get_item_2") # initialise/run method and value will be stored in `session_state`
    

with st.form("get_data_2"):
    st.text_input("key", key="get_local_storage_v_2")
    st.form_submit_button("Submit", on_click=change_state_2)
st.session_state["st_col_test"] = st.columns(1) #to make sure rendering happens below form (or other streamlit element. Else the re-rendering of component upon re-running of up will be run at the top of the streamlit component (form here) which creates nasty ui experience.)


if "test_get_item_2" in st.session_state and st.session_state["test_get_item_2"] != None:
    st.session_state["get_val_2"] = st.session_state["test_get_item_2"] # if local storage method is initialised, get the stored value and use it throughout the app.
st.write(st.session_state["get_val_2"])

Remember to refresh browser if it does not pop up instantly in local storage.