code: func (s *WMailServer) DeliverMail(peer *whisper.Peer, request *whisper.Envelope) {
  	if peer == nil {
  		log.Error("Whisper peer is nil")
  		return
  	}
  
  	ok, lower, upper, bloom := s.validateRequest(peer.ID(), request)
  	if ok {
  		s.processRequest(peer, lower, upper, bloom)
  	}
  }
docs: // DeliverMail responds with saved messages upon request by the
  // messages' owner.