Only subscriber role user can comment not other

Question

I have marked the option - " Users must be registered and logged in to comment " in Admin panel Setting -> Discussion section but i want only subscriber role user can comment not other roles type user.

Thanks,

Answer 1

I suggest adding a snippet to the theme file where the comments form is loaded that checks to make sure there is a logged in user and then, if that user a Subscriber, then show the comments form to them. The examples below use the Twenty Sixteen theme:

In comments.php:

// First, get the current user and check their role
$user = wp_get_current_user();
if ( in_array( 'subscriber', (array) $user->roles ) ) {
    // The current user has the subscriber role, show the form
    comment_form( array(
        'title_reply_before' => '<h2 id="reply-title" class="comment-reply-title">',
        'title_reply_after'  => '</h2>',
    ) );
}

This way, only those users with the subscriber role will see the comments form.

Answer 2

It looks like the first time the core calls wp_get_current_user() is within the WP::init() method.

To better understand the context, we see that it's right after the after_setup_theme hook and just before the init hook ^src:

do_action( 'after_setup_theme' );

// Set up current user.
$GLOBALS['wp']->init();

do_action( 'init' );

where WP::init() is defined as ^src:

public function init() {
    wp_get_current_user();
}

The wp_get_current_user() is a wrapper for _wp_get_current_user() that contains calls to wp_set_current_user() in various ways, e.g. with wp_set_current_user(0) for logged-out users.

Here's one suggestion, hook into the set_current_user action within the wp_set_current_user():

/**
 * Comments only open for users with the 'subscriber' role
 */
add_action( 'set_current_user', function() use ( &$current_user )
{
   if(     $current_user instanceof \WP_User 
        && $current_user->exists() 
        && in_array( 'subscriber', (array) $current_user->roles, true ) 
    )
        return;

    add_filter( 'comments_open', '__return_false' );

} );

If the current user has the subscriber role then do nothing. For all other users or visitors the comments are forced closed.

I might be too cautious checking for the \WP_User object instance, but I keep it anyway, as it's possible to mess with the $current_user, as with many other things in WordPress ;-)

The reason for using $current_user here, instead of calling wp_get_current_user(), is to avoid a possible infinite loop, but there are ways to handle that if needed. It's also tempting to play with the determine_current_user filter.

For visitors (not logged in) the wp_get_current_user() will return a \WP_User object with ID as 0 and roles as an empty array. That's because of the wp_set_current_user(0) calls mentioned earlier.

Here $current_user->exists() is a wrapper for ! empty( $current_user->ID).

I agree with @TammyShipps regarding the array casting of the roles, but as noted by @cybmeta, only hiding the comment form will not stop other users from being able to comment.

Another approach is a little rewrite of my recent answer here:

/**
 * Comments only open for users with the 'subscriber' role
 */
add_action( 'init', function()
{
    $u = wp_get_current_user();

    if( $u->exists() && in_array( 'subscriber', (array) $u->roles, true ) )
        return;

    add_filter( 'comments_open', '__return_false' );
} );

Both of these methods should stop direct POST requests to the wp-comments-post.php file, because of the comments_open() check there. I haven't checked but I think it will also work with xml-rpc.

We might also try the pre_comment_on_post hook to stop the comment handling by e.g. throwing an \WP_Error.

Answer 3

The below code check if user is not subscriber then comment form will not display. Comment form only show when user is login and and user role is subscriber.

  add_filter( 'init', 'manage_comment');

    function manage_comment()
    {
     global $current_user;

     $user_roles = $current_user->roles;
     $user_role = array_shift($user_roles);
    if ($user_role!='subscriber')
    { 
     add_filter( 'comments_open', '__return_false' );
    } 
    }