app.py

import network
from shapely.geometry import Point
import streamlit as st
import config
from utils import (
    set_up_server,
    set_up_client,
    display_encrypted,
    transform_point,
    process_result,
    display_map,
    init_session,
    add_to_server_side,
    add_to_client_side,
    display_client_side,
    display_server_side,
    restart_session,
)
from concrete import fhe

server = set_up_server()
client = set_up_client(server.client_specs.serialize())
restaurants, point_coordinates = network.get()

c1, c2, c3 = init_session()

with c1:
    display_client_side()
with c2:
    st_map = display_map(restaurants)
with c3:
    display_server_side()


# keys generation view
if "evaluation_key" not in st.session_state:
    with c1:
        if st.button("Generate keys"):
            with st.spinner("Generating keys"):
                client.keys.load_if_exists_generate_and_save_otherwise(
                    config.keys_filepath
                )
                st.session_state["evaluation_key"] = client.evaluation_keys.serialize()
                add_to_client_side(
                    "Encryption/decryption keys and evaluation keys are generated."
                )
                add_to_client_side("The evaluation key is sent to the server.")
                add_to_server_side(
                    f"Evaluation key: {display_encrypted(st.session_state['evaluation_key'])}"
                )
            st.rerun()

else:
    if "position" not in st.session_state:
        with c1:
            st.write("Select your starting position on the st_map")

        if st_map.get("last_clicked"):
            position = Point(
                st_map.get("last_clicked")["lng"], st_map.get("last_clicked")["lat"]
            )
            add_to_client_side(
                f"Selected starting point is: ({position.x}, {position.y})"
            )
            st.session_state["position"] = position
            st.rerun()

    if "position" in st.session_state and "encrypted_position" not in st.session_state:
        position = st.session_state["position"]
        with c1:
            if st.button("Encrypt and send inputs"):
                with st.spinner("Encrypting inputs"):
                    client.keys.load(config.keys_filepath)

                    x, y = transform_point(position.x, position.y)
                    encrypted_x, encrypted_y = client.encrypt(x, y)
                    encrypted_position = (
                        encrypted_x.serialize(),
                        encrypted_y.serialize(),
                    )
                    add_to_server_side(
                        f"Received starting point: ({display_encrypted(encrypted_position[0])},{display_encrypted(encrypted_position[1])})"
                    )
                    st.session_state["encrypted_position"] = encrypted_position
                st.rerun()

    if (
        "encrypted_position" in st.session_state
        and "encrypted_results" not in st.session_state
    ):
        with c3:
            encrypted_x = st.session_state["encrypted_position"][0]
            encrypted_y = st.session_state["encrypted_position"][1]

            if st.button(f"Find {config.number_of_neighbors} nearest restaurants"):
                with st.spinner("Computing"):
                    st.write("Please wait, it may take few minutes.")
                    deserialized_x = fhe.Value.deserialize(encrypted_x)
                    deserialized_y = fhe.Value.deserialize(encrypted_y)
                    deserialized_evaluation_keys = fhe.EvaluationKeys.deserialize(
                        st.session_state["evaluation_key"]
                    )
                    client.keys.load_if_exists_generate_and_save_otherwise(
                        config.keys_filepath
                    )
                    res = server.run(
                        deserialized_x,
                        deserialized_y,
                        evaluation_keys=deserialized_evaluation_keys,
                    )
                    ser_res = fhe.Value.serialize(res)
                    add_to_server_side(
                        f"The encrypted result {display_encrypted(ser_res)} is sent to the client."
                    )
                    add_to_client_side(
                        f"The received encrypted result is: {display_encrypted(ser_res)}."
                    )
                    st.session_state["encrypted_results"] = ser_res
                st.rerun()

    if (
        "encrypted_results" in st.session_state
        and "decrypted_result" not in st.session_state
    ):
        res = st.session_state["encrypted_results"]
        with c1:
            if st.button("Decrypt result"):
                with st.spinner("Computing"):
                    client.keys.load_if_exists_generate_and_save_otherwise(
                        config.keys_filepath
                    )
                    deser_res = fhe.Value.deserialize(res)
                    decrypted_result = client.decrypt(deser_res)
                    process_result(restaurants, decrypted_result)
                    st.session_state["decrypted_result"] = decrypted_result
                    st.rerun()

    if "decrypted_result" in st.session_state:
        with c1:
            restart_session()