Authentication and Session Management

def login_user(user, remember=None):
    """
    Log in a user and handle tracking if enabled.
    
    Args:
        user: User instance to log in
        remember (bool, optional): Whether to set remember me cookie
        
    Returns:
        bool: True if login successful
    """

def logout_user():
    """
    Log out the current user.
    Cleans up session and remember cookie, sends identity_changed signal.
    
    Returns:
        bool: True if logout successful
    """

# Current user proxy - automatically updated on login/logout
current_user: Union[User, AnonymousUser]

def url_for_security(endpoint, **values):
    """
    Generate URLs for security blueprint endpoints.
    
    Args:
        endpoint (str): Security endpoint name (e.g., 'login', 'logout')
        **values: Additional URL parameters
        
    Returns:
        str: Generated URL
    """

def hash_password(password):
    """
    Hash a password using the configured password hash.
    
    Args:
        password (str): Plain text password
        
    Returns:
        str: Hashed password
    """

def verify_password(password, password_hash):
    """
    Verify a password against its hash.
    
    Args:
        password (str): Plain text password
        password_hash (str): Hashed password
        
    Returns:
        bool: True if password is correct
    """

def verify_and_update_password(password, user):
    """
    Verify password and update hash if using deprecated scheme.
    
    Args:
        password (str): Plain text password
        user: User instance
        
    Returns:
        bool: True if password is correct
    """

def get_token_status(token, serializer, max_age=None, return_data=False):
    """
    Validate token status and extract data.
    
    Args:
        token (str): Token to validate
        serializer: Serializer instance
        max_age (int, optional): Maximum token age in seconds
        return_data (bool): Whether to return token data
        
    Returns:
        tuple: (expired, invalid, data) status
    """

def get_identity_attributes(app=None):
    """
    Get configured user identity attributes (usually email).
    
    Args:
        app (Flask, optional): Flask application instance
        
    Returns:
        list: List of identity attribute names
    """

from flask import request, redirect, url_for
from flask_security import login_user, logout_user, current_user

@app.route('/custom_login', methods=['POST'])
def custom_login():
    email = request.form.get('email')
    password = request.form.get('password')
    remember = request.form.get('remember', False)
    
    user = user_datastore.find_user(email=email)
    if user and verify_password(password, user.password):
        login_user(user, remember=remember)
        return redirect(url_for('dashboard'))
    
    return "Invalid credentials", 401

@app.route('/custom_logout')
def custom_logout():
    logout_user()
    return redirect(url_for('index'))

from flask_security import current_user

@app.route('/profile')
def profile():
    if current_user.is_authenticated:
        return f"Welcome, {current_user.email}!"
    else:
        return redirect(url_for_security('login'))

@app.template_global()
def is_logged_in():
    return current_user.is_authenticated

from flask_security import hash_password, verify_password

# Hash password for new user
password_hash = hash_password('user_password')
user = user_datastore.create_user(
    email='user@example.com',
    password=password_hash
)

# Verify password during login
if verify_password('user_password', user.password):
    print("Password is correct")

# Update password with verification
def change_password(user, old_password, new_password):
    if verify_password(old_password, user.password):
        user.password = hash_password(new_password)
        user_datastore.put(user)
        user_datastore.commit()
        return True
    return False

from flask_security import current_user

# Get user's authentication token
@app.route('/api/get-token')
def get_auth_token():
    if current_user.is_authenticated:
        token = current_user.get_auth_token()
        return {'token': token}
    return {'error': 'Not authenticated'}, 401

# API endpoint that accepts token authentication
@app.route('/api/data')
def api_data():
    # Token authentication is handled automatically by Flask-Security
    # if SECURITY_AUTH_TOKEN_REQUIRED is configured
    return {'data': 'Protected data'}

from flask_security import url_for_security

# Generate security URLs in templates or views
login_url = url_for_security('login')
logout_url = url_for_security('logout')
register_url = url_for_security('register')

# With additional parameters
login_url_with_next = url_for_security('login', next='/dashboard')

from flask_security import current_user
from datetime import datetime

@app.route('/login_info')
def login_info():
    if current_user.is_authenticated:
        return {
            'last_login_at': current_user.last_login_at,
            'current_login_at': current_user.current_login_at,
            'last_login_ip': current_user.last_login_ip,
            'current_login_ip': current_user.current_login_ip,
            'login_count': current_user.login_count
        }
    return {'error': 'Not authenticated'}, 401

# Login with remember me
login_user(user, remember=True)

# Check if user was remembered
@app.route('/check_remember')
def check_remember():
    # Flask-Login handles remember cookie automatically
    if current_user.is_authenticated:
        return "User is logged in (possibly remembered)"
    return "User not logged in"

from flask_security import login_user, current_user
from flask import session

def authenticate_with_custom_method(username, auth_data):
    """Custom authentication method"""
    user = user_datastore.find_user(username=username)
    
    if user and custom_verify_auth(user, auth_data):
        # Log in the user
        login_user(user)
        
        # Store additional session data
        session['auth_method'] = 'custom'
        session['auth_time'] = datetime.utcnow()
        
        return True
    return False

def custom_verify_auth(user, auth_data):
    """Implement your custom authentication logic"""
    # Example: API key verification, LDAP, OAuth, etc.
    return True  # Replace with actual verification