Does not update tags on member list.

Hi,

I added a filter in a plugin to add tags based on selected checkboxes.
I noticed that the mailchimp api for PUT and PATCH does not actually update the Tags.

I did figure a work-around but it is not great…

Would much prefer it if mailchimp-for-wp could update tags for an existing subscription.

Or maybe if an action could be made passing in the api, list_id, subscriber, existing_member_data after the submission?

Also I can’t really remove tags for my use case as the same list is used across multiple forms/sites so it would be great to have an option configurable on the form to retain the current tags or to replace completely when updating.

I sent a support request to Mailchimp about this, seems odd that updating a member list would not update the tags yet it can create the tags initially just fine.

// Adding tags to Mailchimp subscribers.
// This feature requires Mailchimp for WordPress version 4.4 or higher
function mc4wp_extras_form_subscriber_data($subscriber) {
	// Get post args _mc4wp_tags[] and set onto $subscriber->tags
	if (isset($_POST['_mc4wp_tags'])) {
		$additionalTags = array_filter($_POST['_mc4wp_tags'], 'strlen');
		foreach ($additionalTags as $tag) {
			$subscriber->tags[] = $tag;
		}
	}

	// Note: This work-around is placed below as at the time of writing the MailChimp Patch API did not update Tags on existing member list records.

	// Get the MailChimp API wrapper.
	$api = mc4wp('api');

	// Get the form ID.
	$form_id = $_POST['_mc4wp_form_id'];

	// Get the form.
	/** @var MC4WP_Form $form */
	$form = mc4wp_get_form( $form_id );

	// Get information on the lists that are selected for the form.
	$lists = $form->get_lists();

	$email_address = $subscriber->email_address;

	// Note: This feature is intended to be used with only 1 list selected
	//        should multiple lists be selected for a form it will send multiple
	//        redundant API requests.

	$existing_member_data = null;
	// loop through lists
	foreach ($lists as $list_id) {
		try {
			// Get existing Member Data.
			$existing_member_data = $api->get_list_member( $list_id, $email_address );
		} catch(MC4WP_API_Resource_Not_Found_Exception $e) {
		  // Member does not exist on list continue anyway as this is not a concern the tags will be added
		  // when the MC4WP plugin adds the email to the list.
		  continue;
		} catch ( MC4WP_API_Exception $e ) {
		  // Don't care?		  
		  continue;
		}

		$existing_tags = [];
		foreach ($existing_member_data->tags as $tag) {
			$existing_tags[] = $tag->name;
		}

    	// Merge the tags we are adding into any existing tags and ensure there are no duplicates.
    	$subscriber->tags = array_unique(array_merge($subscriber->tags, $existing_tags), SORT_REGULAR);

		try {
			// Build tags object to send to API.
			$tags = [];
			foreach ($subscriber->tags as $tag) {
				$tags[] = [
					'name' => $tag,
					'status' => 'active'
				];
			}

    		// Update the list member tags.
    		// $subscriber->tags
    		$api->update_list_member_tags( $list_id, $email_address, [ 'tags' => $tags ] );
		} catch(MC4WP_API_Resource_Not_Found_Exception $e) {
		  // Don't care.
		} catch ( MC4WP_API_Exception $e ) {
		  // Don't care?
		  //die($e->getMessage());
		}
	}

	return $subscriber;
}
add_filter("mc4wp_form_subscriber_data", "mc4wp_extras_form_subscriber_data");