I have 2 different domains for NodeJS app and WordPress website hosted on different hosts. The NodeJS app send the user's email to the WordPress domain on Google SSO login to create a user and log him in automatically without the need to create an account on the WordPress. The user gets registered but when I open the website of the WordPress I don't find myself logged-in and I'm using Google Tab On plugin on the WordPress and I'm okay with any alternatives try { // Register user on Node.js const userData = { username: 'john doe', email: googleUser.email, }; // Send user data to WordPress for registration const response = await axios.post('https://wordpress_domain.shop/wp-json/nodejs/v1/register-endpoint', { user: userData, }); // Check if user registration on WordPress was successful if (response.data.success) { // Generate a JWT token const token = jwt.sign(userData, process.env.JWT_SECRET); // Perform an AJAX request to log in the user on the WordPress site await axios.post('https://wordpress_domain.shop/wp-json/nodejs/v1/login-endpoint', { token: token, }); } } catch (error) { console.error('Error sending data to WordPress:', error); } WordPress/PHP add_action('rest_api_init', 'register_custom_endpoints'); function register_custom_endpoints() { register_rest_route('nodejs/v1', '/register-endpoint', array( 'methods' => 'POST', 'callback' => 'handle_user_registration', )); register_rest_route('nodejs/v1', '/login-endpoint', array( 'methods' => 'POST', 'callback' => 'handle_user_login', )); } function handle_user_registration($data) { $username = sanitize_text_field($data['user']['username']); $email = sanitize_email($data['user']['email']); // Check if the user already exists $user_id = username_exists($username); if (!$user_id && email_exists($email) == false) { // User doesn't exist, create a new one $user_id = wp_create_user($username, wp_generate_password(), $email); // Log the user in wp_set_auth_cookie($user_id); return rest_ensure_response(array('success' => true, 'message' => 'User registered successfully.')); } else { return rest_ensure_response(array('success' => false, 'message' => 'User already exists.')); } } function handle_user_login($data) { $token = $data['token']; // Verify the JWT token $decoded = jwt_verify($token); if ($decoded) { // Get user data from the decoded token $username = $decoded['username']; $email = $decoded['email']; // Log in the user $user = get_user_by('email', $email); wp_set_auth_cookie($user->ID); return rest_ensure_response(array('success' => true, 'message' => 'User logged in successfully.')); } else { return rest_ensure_response(array('success' => false, 'message' => 'Invalid token.')); } } // Helper function to verify JWT function jwt_verify($token) { $secretKey = 'testingtoken'; try { $decoded = jwt_decode($token, $secretKey, array('HS256')); return $decoded; } catch (Exception $e) { return false; } }