func printPeer(ps peer.Peerstore, p peer.ID) (interface{}, error) {
	if p == "" {
		return nil, errors.New("Attempted to print nil peer!")
	}

	info := new(IdOutput)
	info.ID = p.Pretty()

	if pk := ps.PubKey(p); pk != nil {
		pkb, err := ic.MarshalPublicKey(pk)
		if err != nil {
			return nil, err
		}
		info.PublicKey = base64.StdEncoding.EncodeToString(pkb)
	}

	for _, a := range ps.Addrs(p) {
		info.Addresses = append(info.Addresses, a.String())
	}

	if v, err := ps.Get(p, "ProtocolVersion"); err == nil {
		if vs, ok := v.(string); ok {
			info.ProtocolVersion = vs
		}
	}
	if v, err := ps.Get(p, "AgentVersion"); err == nil {
		if vs, ok := v.(string); ok {
			info.AgentVersion = vs
		}
	}

	return info, nil
}

func (dht *IpfsDHT) handleAddProvider(ctx context.Context, p peer.ID, pmes *pb.Message) (*pb.Message, error) {
	lm := make(lgbl.DeferredMap)
	lm["peer"] = func() interface{} { return p.Pretty() }

	defer log.EventBegin(ctx, "handleAddProvider", lm).Done()
	key := key.Key(pmes.GetKey())
	lm["key"] = func() interface{} { return key.Pretty() }

	log.Debugf("%s adding %s as a provider for '%s'\n", dht.self, p, key)

	// add provider should use the address given in the message
	pinfos := pb.PBPeersToPeerInfos(pmes.GetProviderPeers())
	for _, pi := range pinfos {
		if pi.ID != p {
			// we should ignore this provider reccord! not from originator.
			// (we chould sign them and check signature later...)
			log.Debugf("handleAddProvider received provider %s from %s. Ignore.", pi.ID, p)
			continue
		}

		if len(pi.Addrs) < 1 {
			log.Debugf("%s got no valid addresses for provider %s. Ignore.", dht.self, p)
			continue
		}

		log.Infof("received provider %s for %s (addrs: %s)", p, key, pi.Addrs)
		if pi.ID != dht.self { // dont add own addrs.
			// add the received addresses to our peerstore.
			dht.peerstore.AddAddrs(pi.ID, pi.Addrs, peer.ProviderAddrTTL)
		}
		dht.providers.AddProvider(ctx, key, p)
	}

	return nil, nil
}

func logRoutingErrDifferentPeers(ctx context.Context, wanted, got peer.ID, err error) {
	lm := make(lgbl.DeferredMap)
	lm["error"] = err
	lm["wantedPeer"] = func() interface{} { return wanted.Pretty() }
	lm["gotPeer"] = func() interface{} { return got.Pretty() }
	log.Event(ctx, "routingError", lm)
}

func pingPeer(ctx context.Context, n *core.IpfsNode, pid peer.ID, numPings int) <-chan interface{} {
	outChan := make(chan interface{})
	go func() {
		defer close(outChan)

		if len(n.Peerstore.Addrs(pid)) == 0 {
			// Make sure we can find the node in question
			outChan <- &PingResult{
				Text: fmt.Sprintf("Looking up peer %s", pid.Pretty()),
			}

			ctx, cancel := context.WithTimeout(ctx, kPingTimeout)
			defer cancel()
			p, err := n.Routing.FindPeer(ctx, pid)
			if err != nil {
				outChan <- &PingResult{Text: fmt.Sprintf("Peer lookup error: %s", err)}
				return
			}
			n.Peerstore.AddAddrs(p.ID, p.Addrs, peer.TempAddrTTL)
		}

		outChan <- &PingResult{Text: fmt.Sprintf("PING %s.", pid.Pretty())}

		ctx, cancel := context.WithTimeout(ctx, kPingTimeout*time.Duration(numPings))
		defer cancel()
		pings, err := n.Ping.Ping(ctx, pid)
		if err != nil {
			log.Debugf("Ping error: %s", err)
			outChan <- &PingResult{Text: fmt.Sprintf("Ping error: %s", err)}
			return
		}

		var done bool
		var total time.Duration
		for i := 0; i < numPings && !done; i++ {
			select {
			case <-ctx.Done():
				done = true
				break
			case t, ok := <-pings:
				if !ok {
					done = true
					break
				}

				outChan <- &PingResult{
					Success: true,
					Time:    t,
				}
				total += t
				time.Sleep(time.Second)
			}
		}
		averagems := total.Seconds() * 1000 / float64(numPings)
		outChan <- &PingResult{
			Text: fmt.Sprintf("Average latency: %.2fms", averagems),
		}
	}()
	return outChan
}

// Unlock releases waiters to a dial attempt. see Lock.
// if Unlock(p) is called without calling Lock(p) first, Unlock panics.
func (ds *dialsync) Unlock(dst peer.ID) {
	ds.lock.Lock()
	wait, found := ds.ongoing[dst]
	if !found {
		panic("called dialDone with no ongoing dials to peer: " + dst.Pretty())
	}
	delete(ds.ongoing, dst) // remove ongoing dial
	close(wait)             // release everyone else
	ds.lock.Unlock()
}

// Dial metadata is metadata for dial events
func Dial(sys string, lid, rid peer.ID, laddr, raddr ma.Multiaddr) DeferredMap {
	m := DeferredMap{}
	m["subsystem"] = sys
	if lid != "" {
		m["localPeer"] = func() interface{} { return lid.Pretty() }
	}
	if laddr != nil {
		m["localAddr"] = func() interface{} { return laddr.String() }
	}
	if rid != "" {
		m["remotePeer"] = func() interface{} { return rid.Pretty() }
	}
	if raddr != nil {
		m["remoteAddr"] = func() interface{} { return raddr.String() }
	}
	return m
}

func (dht *IpfsDHT) handleGetProviders(ctx context.Context, p peer.ID, pmes *pb.Message) (*pb.Message, error) {
	lm := make(lgbl.DeferredMap)
	lm["peer"] = func() interface{} { return p.Pretty() }
	defer log.EventBegin(ctx, "handleGetProviders", lm).Done()

	resp := pb.NewMessage(pmes.GetType(), pmes.GetKey(), pmes.GetClusterLevel())
	key := key.Key(pmes.GetKey())
	lm["key"] = func() interface{} { return key.Pretty() }

	// debug logging niceness.
	reqDesc := fmt.Sprintf("%s handleGetProviders(%s, %s): ", dht.self, p, key)
	log.Debugf("%s begin", reqDesc)
	defer log.Debugf("%s end", reqDesc)

	// check if we have this value, to add ourselves as provider.
	has, err := dht.datastore.Has(key.DsKey())
	if err != nil && err != ds.ErrNotFound {
		log.Debugf("unexpected datastore error: %v\n", err)
		has = false
	}

	// setup providers
	providers := dht.providers.GetProviders(ctx, key)
	if has {
		providers = append(providers, dht.self)
		log.Debugf("%s have the value. added self as provider", reqDesc)
	}

	if providers != nil && len(providers) > 0 {
		infos := peer.PeerInfos(dht.peerstore, providers)
		resp.ProviderPeers = pb.PeerInfosToPBPeers(dht.host.Network(), infos)
		log.Debugf("%s have %d providers: %s", reqDesc, len(providers), infos)
	}

	// Also send closer peers.
	closer := dht.betterPeersToQuery(pmes, p, CloserPeerCount)
	if closer != nil {
		infos := peer.PeerInfos(dht.peerstore, closer)
		resp.CloserPeers = pb.PeerInfosToPBPeers(dht.host.Network(), infos)
		log.Debugf("%s have %d closer peers: %s", reqDesc, len(closer), infos)
	}

	return resp, nil
}

func peersTotalGauge(id peer.ID) prom.Gauge {
	return peersTotal.With(prom.Labels{"peer_id": id.Pretty()})
}