code: func (m *Manager) GetAuthorizationsByUser(username string) (authorizations []Authorization, err error) {
  	err = m.getAuthorizationCollection().Find(bson.M{"username": username}).All(&authorizations)
  	if authorizations == nil {
  		authorizations = []Authorization{}
  	}
  	return
  }
docs: // GetAuthorizationsByUser returns all authorizations for a specific user