firebase streamlit

backend.py

from flask import Flask, request, jsonify
from flask_cors import CORS
import requests
import os
from dotenv import load_dotenv
import re

load_dotenv()
app = Flask(__name__)
CORS(app)  # Enable CORS for frontend communication

FIREBASE_API_KEY = os.getenv("FIREBASE_API_KEY")

# Helper function for Firebase requests
def firebase_request(url, data):
    response = requests.post(
        f"https://identitytoolkit.googleapis.com/v1/accounts:{url}?key={FIREBASE_API_KEY}",
        json=data
    )
    return response.json()

# Email validation regex
def is_valid_email(email):
    return re.match(r"[^@]+@[^@]+\.[^@]+", email)

@app.route('/signup', methods=['POST'])
def signup():
    data = request.get_json()
    email = data.get('email')
    password = data.get('password')

    # Validation
    if not email or not password:
        return jsonify({"error": "Email and password are required"}), 400
    if not is_valid_email(email):
        return jsonify({"error": "Invalid email format"}), 400
    if len(password) < 6:
        return jsonify({"error": "Password must be at least 6 characters"}), 400

    try:
        # Create user in Firebase
        result = firebase_request('signUp', {
            "email": email,
            "password": password,
            "returnSecureToken": True
        })
        
        if 'error' in result:
            return jsonify({"error": result['error']['message']}), 400
            
        return jsonify({
            "message": "User created successfully",
            "user_id": result['localId']
        }), 201

    except Exception as e:
        return jsonify({"error": str(e)}), 500

@app.route('/signin', methods=['POST'])
def signin():
    data = request.get_json()
    email = data.get('email')
    password = data.get('password')

    if not email or not password:
        return jsonify({"error": "Email and password are required"}), 400

    try:
        # Authenticate user
        result = firebase_request('signInWithPassword', {
            "email": email,
            "password": password,
            "returnSecureToken": True
        })

        if 'error' in result:
            return jsonify({"error": result['error']['message']}), 401
        
        print(result['idToken'])
        
        return jsonify({
            "message": "Login successful",
            "user_id": result['localId'],
            "email": result['email'],
            "token": result['idToken']
        }), 200

    except Exception as e:
        return jsonify({"error": str(e)}), 500

if __name__ == '__main__':
    app.run(debug=True, port=5000)

frontend.py

import streamlit as st
import requests

BACKEND_URL = "http://localhost:5000"  # Flask backend URL

st.title("Firebase Authentication")

# Signup Section
with st.expander("Sign Up"):
    with st.form("signup_form"):
        signup_email = st.text_input("Email", key="signup_email")
        signup_password = st.text_input("Password", type="password", key="signup_password")
        signup_submit = st.form_submit_button("Create Account")

    if signup_submit:
        response = requests.post(
            f"{BACKEND_URL}/signup",
            json={"email": signup_email, "password": signup_password}
        )
        
        if response.status_code == 201:
            st.success("Account created successfully!")
        else:
            error = response.json().get('error', 'Unknown error')
            st.error(f"Signup failed: {error}")

# Login Section
with st.expander("Sign In"):
    with st.form("login_form"):
        login_email = st.text_input("Email", key="login_email")
        login_password = st.text_input("Password", type="password", key="login_password")
        login_submit = st.form_submit_button("Login")

    if login_submit:
        response = requests.post(
            f"{BACKEND_URL}/signin",
            json={"email": login_email, "password": login_password}
        )
        
        if response.status_code == 200:
            user_data = response.json()
            st.success(f"Welcome {user_data['email']}!")
            st.session_state.user = user_data
        else:
            error = response.json().get('error', 'Unknown error')
            st.error(f"Login failed: {error}")

# Display user session
if 'user' in st.session_state:
    st.subheader("Current Session")
    st.write(f"Logged in as: {st.session_state.user['email']}")
    if st.button("Logout"):
        del st.session_state.user
        st.experimental_rerun()