How to display the user that published a pending post?

Question

I am trying to list the name of the moderators (users with editor role) that publish pending posts. I created a dashboard widget that shows the latest 10 published posts and the author, but I have problems getting the user that published it. I thought the_modified_author might be it, but I'm not sure if there's a better way to tell who published the post? Either way, my method isn't working. Here's my code so far:

function dashboard_widget_function() {

    $args = array( 'post_status' => 'publish', 'numberposts' => '10', 'post_type' => 'post');

        $recent_posts = wp_get_recent_posts( $args );

     echo '<table><tr>
    <th>Post Title</th>
    <th>Author</th>
    <th>Moderated by</th></tr>';

        foreach( $recent_posts as $recent ){ 
            $post_author = get_user_by( 'id', $recent['post_author'] );
            echo '<tr><td><a href="' . get_permalink($recent["ID"]) . '" title="Read: '.esc_attr($recent["post_title"]).'" >' .   $recent["post_title"].'</a></td>';
            echo '<td>'. $post_author->display_name .'</td>';
            echo '<td>'.get_the_modified_author().'</td></tr>';

        }
        echo '</table>';
}

Answer 1

The reason that get_the_modified_author() is not working is that it relies on being used within the WordPress loop. wp_get_recent_posts() does not set up a global post object. Here is a complete example based on your original code that replaces get_the_modified_author() with some simple code to get the name of the last person who edited the post (which is essentially what get_the_modified_author() does):

/**
 * Add a widget to the dashboard.
 *
 * This function is hooked into the 'wp_dashboard_setup' action below.
 */
function example_add_dashboard_widgets() {
    wp_add_dashboard_widget(
        'example_dashboard_widget', // Widget slug.
        'Example Dashboard Widget', // Title.
        'example_dashboard_widget_function' // Display function.
    );  
}
add_action( 'wp_dashboard_setup', 'example_add_dashboard_widgets' );

function example_dashboard_widget_function() {
    $items_to_show = 10;
    $counter       = 0;
    $recent_posts  = wp_get_recent_posts( [
        'post_status' => 'publish',
        'numberposts' => '50', // More than we want, but tries to ensure we have enough items to display.
        'post_type'   => 'post'
    ] );

    echo '<table>
                    <tr>
                        <th>Post Title</th>
                        <th>Author</th>
                        <th>Moderated by</th>
                    </tr>';

    foreach ( $recent_posts as $recent ) {
        $post_author  = get_user_by( 'id', $recent['post_author'] );
        $last_user_id = get_post_meta( $recent['ID'], '_edit_last', true );
        $last_user    = get_userdata( $last_user_id );

        // Bail out of the loop if we've shown enough items.
        if ( $counter >= $items_to_show ) {
            break;
        }

        // Skip display of items where the author is the same as the moderator:
        if ( $post_author->display_name === $last_user->display_name ) {
            continue;
        }

        echo '<tr><td><a href="' . get_permalink( $recent['ID'] ) . '" title="Read: ' . 
            esc_attr( $recent['post_title'] ).'" >' .   $recent['post_title'].'</a></td>';
        echo '<td>'. esc_html( $post_author->display_name ) .'</td>';

        echo '<td>'. esc_html( $last_user->display_name ) .'</td></tr>';

        $counter++;
    }
    echo '</table>';
}

Edit based on feedback from comment: This code skips the display of items where $post_author->display_name === $last_user->display_name. It's not the most efficient code though, since we're querying more items than needed. This is done because we'll skip some items and we want to (try) to ensure that there are at least 10 items to display ($items_to_show = 10).

Answer 2

We could save the id of the user that last published a post, as the value of the _wpse_user_last_published post meta key, with:

add_action( 'transition_post_status', function( $new_status, $old_status, $post )
{
    if( 
           $new_status !== $old_status 
        && 'publish' === $new_status 
        && 'post' === get_post_type( $post ) 
    )
        update_post_meta( $post->ID, '_wpse_user_last_published', get_current_user_id() );

}, 10, 3 );

Then you could fetch this info when you list your posts.

For more detail and faster search, it might be better to create a custom log table.