Question

I’ll show a custom – error message.

function ccl($data, $postarr = '') {
 if($data['post_status'] == "publish"){
  $data['post_status'] = "draft"; 
  echo '<div id="my-custom-error" class="error fade"><p>Publish not allowed</p></div>';
 }  
  return $data;
}

add_filter( 'wp_insert_post_data' , 'ccl' , '99' );

I’ve try many thinks but everytime a success message comes from wordpress that the article published. Can i kill the success message and show my own error message?

tanks for help…

Answer 1

You can’t print an error in a wp_insert_post_data filter because the user is redirected immediately after this. The best thing to do is to hook into the redirect filter and add a message variable to the query string (this will overwrite any existing WordPress message).

So, add the redirect filter in your wp_insert_post_data filter function.

add_filter('wp_insert_post_data', 'ccl', 99);
function ccl($data) {
  if ($data['post_type'] !== 'revision' && $data['post_status'] == 'publish') {
    $data['post_status'] = 'draft';
    add_filter('redirect_post_location', 'my_redirect_post_location_filter', 99);
  }
  return $data;
}

Then add a message variable in the redirect filter function.

function my_redirect_post_location_filter($location) {
  remove_filter('redirect_post_location', __FUNCTION__, 99);
  $location = add_query_arg('message', 99, $location);
  return $location;
}

Finally hook into the post_updated_messages filter and add your message so WordPress knows what to print.

add_filter('post_updated_messages', 'my_post_updated_messages_filter');
function my_post_updated_messages_filter($messages) {
  $messages['post'][99] = 'Publish not allowed';
  return $messages;
}