How do I get a list the comment types' machine name?

Question

Drupal ships with just one comment type enabled, with the machine name comment. But if the Forum module is installed, there is also comment_forum. And site builders can define new comment types in the GUI.

How do I get a list the comment types' machine name? Or: How can I get all comments, regardless of name.

Answer 1

Comment types are an entity type, so you can load them as with any entity type, and get the machine name from CommentType::id():

$comment_types = array_map(
  function ($comment_type) {
    return $comment_type->id();
  },
  \Drupal::entityTypeManager()->getStorage('comment_type')->loadMultiple()
);

Or to load all comments, regardless of type, you can use:

\Drupal::entityTypeManager()->getStorage('comment')->loadMultiple()