Elgg / Elgg

mod/groups/actions/groups/membership/add.php

<?php
/**
 * Add users to a group
 *
 * @package ElggGroups
 */
$logged_in_user = elgg_get_logged_in_user_entity();

$user_guid = get_input('user_guid');
if (!is_array($user_guid)) {
	$user_guid = [$user_guid];
}
$group_guid = get_input('group_guid');
$group = get_entity($group_guid);
if (!($group instanceof ElggGroup) || !$group->canEdit()) {

This code seems to be duplicated across your project.

	register_error(elgg_echo('actionunauthorized'));
	forward(REFERER);
}

$errors = [];
if (sizeof($user_guid)) {
	foreach ($user_guid as $u_guid) {
		$user = get_user($u_guid);
		if (empty($user)) {
			continue;
		}
		
		if (!$group->isMember($user)) {
			if (groups_join_group($group, $user)) {
				$subject = elgg_echo('groups:welcome:subject', [$group->name], $user->language);

				$body = elgg_echo('groups:welcome:body', [
					$user->name,
					$group->name,
					$group->getURL(),
				], $user->language);
				
				$params = [
					'action' => 'add_membership',
					'object' => $group,
					'url' => $group->getURL(),
				];

				// Send welcome notification to user
				notify_user($user->getGUID(), $group->owner_guid, $subject, $body, $params);

				system_message(elgg_echo('groups:addedtogroup'));
			} else {
				$errors[] = elgg_echo('groups:error:addedtogroup', [$user->name]);
			}
		} else {
			$errors[] = elgg_echo('groups:add:alreadymember', [$user->name]);

			// if an invitation is still pending clear it up, we don't need it
			remove_entity_relationship($group->guid, 'invited', $user->guid);
			
			// if a membership request is still pending clear it up, we don't need it
			remove_entity_relationship($user->guid, 'membership_request', $group->guid);
		}
	}
}

if ($errors) {
	foreach ($errors as $error) {
		register_error($error);
	}
}

forward(REFERER);