st_file_uploader.py

# Copyright (c) Streamlit Inc. (2018-2022) Snowflake Inc. (2022-2024)
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

import streamlit as st
from streamlit import runtime

single_file = st.file_uploader("Drop a file:", type=["txt"], key="single")
if single_file is None:
    st.text("No upload")
else:
    st.text(single_file.read())

# Here and throughout this file, we use `if runtime.is_running():`
# since we also run e2e python files in "bare Python mode" as part of our
# Python tests, and this doesn't work in that circumstance
# st.session_state can only be accessed while running with streamlit
if runtime.exists():
    st.write(repr(st.session_state.single) == repr(single_file))

disabled = st.file_uploader(
    "Can't drop a file:", type=["txt"], key="disabled", disabled=True
)
if disabled is None:
    st.text("No upload")
else:
    st.text(disabled.read())

if runtime.exists():
    st.write(repr(st.session_state.disabled) == repr(disabled))

multiple_files = st.file_uploader(
    "Drop multiple files:",
    type=["txt"],
    accept_multiple_files=True,
    key="multiple",
)
if multiple_files is None:
    st.text("No upload")
else:
    files = [file.read().decode() for file in multiple_files]
    st.text("\n".join(files))

if runtime.exists():
    st.write(repr(st.session_state.multiple) == repr(multiple_files))

with st.form("foo"):
    form_file = st.file_uploader("Inside form:", type=["txt"])
    st.form_submit_button("Submit")
    if form_file is None:
        st.text("No upload")
    else:
        st.text(form_file.read())


hidden_label = st.file_uploader(
    "Hidden label:",
    key="hidden_label",
    label_visibility="hidden",
)

if hidden_label is None:
    st.text("No upload")
else:
    st.text(hidden_label.read())

if runtime.exists():
    st.write(repr(st.session_state.hidden_label) == repr(hidden_label))

collapsed_label = st.file_uploader(
    "Collapsed label:",
    key="collapsed_label",
    label_visibility="collapsed",
)

if collapsed_label is None:
    st.text("No upload")
else:
    st.text(collapsed_label.read())

if runtime.exists():
    st.write(repr(st.session_state.collapsed_label) == repr(collapsed_label))

if runtime.exists():
    if not st.session_state.get("counter"):
        st.session_state["counter"] = 0

    def file_uploader_on_change():
        st.session_state.counter += 1

    st.file_uploader(
        "Drop a file:",
        type=["txt"],
        key="on_change_file_uploader_key",
        on_change=file_uploader_on_change,
    )

    st.text(st.session_state.counter)