/**
  * @param Organization $orga
  * @return array
  */
 private function getLinks(Organization $orga)
 {
     return ['_links' => [['rel' => 'self', 'uri' => '/api/public/orgas/' . $orga->getLogin()], ['rel' => 'orga.image', 'uri' => '/uploads/logos/' . $orga->getAvatar()], ['rel' => 'orga.president', 'uri' => $orga->getPresident() ? '/api/public/users/' . $orga->getPresident()->getLogin() : null], ['rel' => 'orga.members', 'uri' => '/api/public/orgas/' . $orga->getLogin() . '/members']]];
 }