wp_login_form() passing user ID into URL on redirect?

Question

I have a custom page where I ask users to log in to access the page. Once they log in, I would like to redirect them to the same page but I want to add on their user ID to the URL string in the redirect. This is just for analytics, the actual content is being protected by if (current_user_can('')){}

Here's the code I have tried in my password protected page:

<?php
    $userID = get_current_user_id();

    $args = array(
        'echo'           => true,
        'remember'       => true,
        'redirect'       => ( is_ssl() ? 'https://' : 'http://' ) . $_SERVER['HTTP_HOST'] . $_SERVER['REQUEST_URI'] . '?uid=' . $userID,
        'form_id'        => 'loginform',
        'id_username'    => 'user_login',
        'id_password'    => 'user_pass',
        'id_remember'    => 'rememberme',
        'id_submit'      => 'wp-submit',
        'label_username' => __( 'Username or Email Address' ),
        'label_password' => __( 'Password' ),
        'label_remember' => __( 'Remember Me' ),
        'label_log_in'   => __( 'Log In' ),
        'value_username' => '',
        'value_remember' => false
    );
    wp_login_form($args);

?>

Obviously this won't work(returns "0") since it's trying to get the user's ID before they're logged in, but I can't think of how I would go about this.

Answer 1

you can add the user identifier à the redirection URL with this filter

add_filter("login_redirect", function ($redirect_to, $requested_redirect_to, $user) {

    $redirect_to = add_query_arg([
        "user_id" => $user->ID,
    ], $redirect_to);


    return $redirect_to;

}, 10, 3);

Answer 2

I was able to resolve this by separating the login page from the page with the content. So I have one page that has the login form and at the top it checks if the user is logged in, if they are, it redirects them to the protected content page with their User ID in the URL, otherwise it displays the login form.