// NewDHT creates a new DHT object with the given peer as the 'local' host
func NewDHT(ctx context.Context, p peer.Peer, ps peer.Peerstore, dialer inet.Dialer, sender inet.Sender, dstore ds.Datastore) *IpfsDHT {
dht := new(IpfsDHT)
dht.dialer = dialer
dht.sender = sender
dht.datastore = dstore
dht.self = p
dht.peerstore = ps
dht.ContextCloser = ctxc.NewContextCloser(ctx, nil)
dht.providers = NewProviderManager(dht.Context(), p.ID())
dht.AddCloserChild(dht.providers)
dht.routingTables = make([]*kb.RoutingTable, 3)
dht.routingTables[0] = kb.NewRoutingTable(20, kb.ConvertPeerID(p.ID()), time.Millisecond*1000)
dht.routingTables[1] = kb.NewRoutingTable(20, kb.ConvertPeerID(p.ID()), time.Millisecond*1000)
dht.routingTables[2] = kb.NewRoutingTable(20, kb.ConvertPeerID(p.ID()), time.Hour)
dht.birth = time.Now()
dht.Validators = make(map[string]ValidatorFunc)
dht.Validators["pk"] = ValidatePublicKeyRecord
if doPinging {
dht.Children().Add(1)
go dht.PingRoutine(time.Second * 10)
}
return dht
}
// Find specific Peer
// FindPeer searches for a peer with given ID.
func (dht *IpfsDHT) FindPeer(ctx context.Context, id peer.ID) (peer.Peer, error) {
// Check if were already connected to them
p, _ := dht.FindLocal(id)
if p != nil {
return p, nil
}
routeLevel := 0
closest := dht.routingTables[routeLevel].NearestPeers(kb.ConvertPeerID(id), AlphaValue)
if closest == nil || len(closest) == 0 {
return nil, kb.ErrLookupFailure
}
// Sanity...
for _, p := range closest {
if p.ID().Equal(id) {
log.Error("Found target peer in list of closest peers...")
return p, nil
}
}
// setup the Query
query := newQuery(u.Key(id), dht.dialer, func(ctx context.Context, p peer.Peer) (*dhtQueryResult, error) {
pmes, err := dht.findPeerSingle(ctx, p, id, routeLevel)
if err != nil {
return nil, err
}
closer := pmes.GetCloserPeers()
var clpeers []peer.Peer
for _, pbp := range closer {
np, err := dht.getPeer(peer.ID(pbp.GetId()))
if err != nil {
log.Warningf("Received invalid peer from query: %v", err)
continue
}
ma, err := pbp.Address()
if err != nil {
log.Warning("Received peer with bad or missing address.")
continue
}
np.AddAddress(ma)
if pbp.GetId() == string(id) {
return &dhtQueryResult{
peer: np,
success: true,
}, nil
}
clpeers = append(clpeers, np)
}
return &dhtQueryResult{closerPeers: clpeers}, nil
})
// run it!
result, err := query.Run(ctx, closest)
if err != nil {
return nil, err
}
log.Debugf("FindPeer %v %v", id, result.success)
if result.peer == nil {
return nil, routing.ErrNotFound
}
return result.peer, nil
}