Jarves\Client\UserProvider::loadUserByUsername PHP Method

    public function loadUserByUsername($username)
    {
        //todo, check if email auth is enabled
        return UserQuery::create()->filterByActivate(true)->filterByUsername($username)->findOne();
    }

 /**
  * @param string $username
  * @param string $password
  * @param null|string $requiredGroupRole
  * @return bool
  */
 public function login($username, $password, $requiredGroupRole = null)
 {
     if (empty($username) || empty($password)) {
         return false;
     }
     $user = $this->userProvider->loadUserByUsername($username);
     if (!$user) {
         $this->logger->warning(sprintf('Login failed for "%s". User not found', $username));
         sleep(1);
         return false;
     }
     if (null !== $requiredGroupRole) {
         $groupRoles = $user->getGroupRoles();
         if (!in_array($requiredGroupRole, $groupRoles)) {
             $this->logger->warning(sprintf('Login failed for "%s". Not in requested group role "%s" vs "%s"', $username, $requiredGroupRole, implode(',', $groupRoles)));
             sleep(1);
             return false;
         }
     }
     $encoder = $this->encoderFactory->getEncoder($user);
     if (!$encoder->isPasswordValid($user->getPassword(), $password, null)) {
         $this->logger->warning(sprintf('Login failed for "%s". Password missmatch ', $username));
         sleep(1);
         return false;
     }
     $this->manualLogin($user);
     return true;
 }