Golang Message.GetKey方法代码示例

func (dht *IpfsDHT) handleAddProvider(p peer.Peer, pmes *pb.Message) (*pb.Message, error) {
	key := u.Key(pmes.GetKey())

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

	// add provider should use the address given in the message
	for _, pb := range pmes.GetProviderPeers() {
		pid := peer.ID(pb.GetId())
		if pid.Equal(p.ID()) {

			addr, err := pb.Address()
			if err != nil {
				log.Errorf("provider %s error with address %s", p, *pb.Addr)
				continue
			}

			log.Infof("received provider %s %s for %s", p, addr, key)
			p.AddAddress(addr)
			dht.providers.AddProvider(key, p)

		} else {
			log.Errorf("handleAddProvider received provider %s from %s", pid, p)
		}
	}

	return pmes, nil // send back same msg as confirmation.
}

func (dht *IpfsDHT) handleFindPeer(p peer.Peer, pmes *pb.Message) (*pb.Message, error) {
	resp := pb.NewMessage(pmes.GetType(), "", pmes.GetClusterLevel())
	var closest []peer.Peer

	// if looking for self... special case where we send it on CloserPeers.
	if peer.ID(pmes.GetKey()).Equal(dht.self.ID()) {
		closest = []peer.Peer{dht.self}
	} else {
		closest = dht.betterPeersToQuery(pmes, CloserPeerCount)
	}

	if closest == nil {
		log.Errorf("handleFindPeer: could not find anything.")
		return resp, nil
	}

	var withAddresses []peer.Peer
	for _, p := range closest {
		if len(p.Addresses()) > 0 {
			withAddresses = append(withAddresses, p)
		}
	}

	for _, p := range withAddresses {
		log.Debugf("handleFindPeer: sending back '%s'", p)
	}
	resp.CloserPeers = pb.PeersToPBPeers(withAddresses)
	return resp, nil
}

// betterPeerToQuery returns nearestPeersToQuery, but iff closer than self.
func (dht *IpfsDHT) betterPeersToQuery(pmes *pb.Message, count int) []peer.Peer {
	closer := dht.nearestPeersToQuery(pmes, count)

	// no node? nil
	if closer == nil {
		return nil
	}

	// == to self? thats bad
	for _, p := range closer {
		if p.ID().Equal(dht.self.ID()) {
			log.Error("Attempted to return self! this shouldnt happen...")
			return nil
		}
	}

	var filtered []peer.Peer
	for _, p := range closer {
		// must all be closer than self
		key := u.Key(pmes.GetKey())
		if !kb.Closer(dht.self.ID(), p.ID(), key) {
			filtered = append(filtered, p)
		}
	}

	// ok seems like closer nodes
	return filtered
}

// nearestPeersToQuery returns the routing tables closest peers.
func (dht *IpfsDHT) nearestPeersToQuery(pmes *pb.Message, count int) []peer.Peer {
	level := pmes.GetClusterLevel()
	cluster := dht.routingTables[level]

	key := u.Key(pmes.GetKey())
	closer := cluster.NearestPeers(kb.ConvertKey(key), count)
	return closer
}

func (dht *IpfsDHT) handleGetProviders(p peer.Peer, pmes *pb.Message) (*pb.Message, error) {
	resp := pb.NewMessage(pmes.GetType(), pmes.GetKey(), pmes.GetClusterLevel())

	// check if we have this value, to add ourselves as provider.
	log.Debugf("handling GetProviders: '%s'", u.Key(pmes.GetKey()))
	dsk := u.Key(pmes.GetKey()).DsKey()
	has, err := dht.datastore.Has(dsk)
	if err != nil && err != ds.ErrNotFound {
		log.Errorf("unexpected datastore error: %v\n", err)
		has = false
	}

	// setup providers
	providers := dht.providers.GetProviders(u.Key(pmes.GetKey()))
	if has {
		providers = append(providers, dht.self)
	}

	// if we've got providers, send thos those.
	if providers != nil && len(providers) > 0 {
		resp.ProviderPeers = pb.PeersToPBPeers(providers)
	}

	// Also send closer peers.
	closer := dht.betterPeersToQuery(pmes, CloserPeerCount)
	if closer != nil {
		resp.CloserPeers = pb.PeersToPBPeers(closer)
	}

	return resp, nil
}

// Store a value in this peer local storage
func (dht *IpfsDHT) handlePutValue(p peer.Peer, pmes *pb.Message) (*pb.Message, error) {
	dht.dslock.Lock()
	defer dht.dslock.Unlock()
	dskey := u.Key(pmes.GetKey()).DsKey()

	err := dht.verifyRecord(pmes.GetRecord())
	if err != nil {
		fmt.Println(u.Key(pmes.GetRecord().GetAuthor()))
		log.Error("Bad dht record in put request")
		return nil, err
	}

	data, err := proto.Marshal(pmes.GetRecord())
	if err != nil {
		return nil, err
	}

	err = dht.datastore.Put(dskey, data)
	log.Debugf("%s handlePutValue %v\n", dht.self, dskey)
	return pmes, err
}

func (dht *IpfsDHT) handleGetValue(p peer.Peer, pmes *pb.Message) (*pb.Message, error) {
	log.Debugf("%s handleGetValue for key: %s\n", dht.self, pmes.GetKey())

	// setup response
	resp := pb.NewMessage(pmes.GetType(), pmes.GetKey(), pmes.GetClusterLevel())

	// first, is the key even a key?
	key := pmes.GetKey()
	if key == "" {
		return nil, errors.New("handleGetValue but no key was provided")
	}

	// let's first check if we have the value locally.
	log.Debugf("%s handleGetValue looking into ds", dht.self)
	dskey := u.Key(pmes.GetKey()).DsKey()
	iVal, err := dht.datastore.Get(dskey)
	log.Debugf("%s handleGetValue looking into ds GOT %v", dht.self, iVal)

	// if we got an unexpected error, bail.
	if err != nil && err != ds.ErrNotFound {
		return nil, err
	}

	// Note: changed the behavior here to return _as much_ info as possible
	// (potentially all of {value, closer peers, provider})

	// if we have the value, send it back
	if err == nil {
		log.Debugf("%s handleGetValue success!", dht.self)

		byts, ok := iVal.([]byte)
		if !ok {
			return nil, fmt.Errorf("datastore had non byte-slice value for %v", dskey)
		}

		rec := new(pb.Record)
		err := proto.Unmarshal(byts, rec)
		if err != nil {
			log.Error("Failed to unmarshal dht record from datastore")
			return nil, err
		}

		resp.Record = rec
	}

	// if we know any providers for the requested value, return those.
	provs := dht.providers.GetProviders(u.Key(pmes.GetKey()))
	if len(provs) > 0 {
		log.Debugf("handleGetValue returning %d provider[s]", len(provs))
		resp.ProviderPeers = pb.PeersToPBPeers(provs)
	}

	// Find closest peer on given cluster to desired key and reply with that info
	closer := dht.betterPeersToQuery(pmes, CloserPeerCount)
	if closer != nil {
		for _, p := range closer {
			log.Debugf("handleGetValue returning closer peer: '%s'", p)
			if len(p.Addresses()) < 1 {
				log.Critical("no addresses on peer being sent!")
			}
		}
		resp.CloserPeers = pb.PeersToPBPeers(closer)
	}

	return resp, nil
}