提交 2f2808e9 作者: Juan Batiz-Benet 提交者: Brian Tiger Chow

handleGetValue

上级 9c5c49b6
...@@ -185,75 +185,98 @@ func (dht *IpfsDHT) handlerForMsgType(t Message_MessageType) dhtHandler { ...@@ -185,75 +185,98 @@ func (dht *IpfsDHT) handlerForMsgType(t Message_MessageType) dhtHandler {
} }
func (dht *IpfsDHT) putValueToNetwork(p *peer.Peer, key string, value []byte) error { func (dht *IpfsDHT) putValueToNetwork(p *peer.Peer, key string, value []byte) error {
pmes := Message{ typ := Message_PUT_VALUE
Type: PBDHTMessage_PUT_VALUE, pmes := &Message{
Key: key, Type: &typ,
Key: &key,
Value: value, Value: value,
ID: swarm.GenerateMessageID(),
} }
mes := swarm.NewMessage(p, pmes.ToProtobuf()) mes, err := msg.FromObject(p, pmes)
dht.netChan.Outgoing <- mes if err != nil {
return nil return err
}
return dht.sender.SendMessage(context.TODO(), mes)
} }
func (dht *IpfsDHT) handleGetValue(p *peer.Peer, pmes *PBDHTMessage) { func (dht *IpfsDHT) handleGetValue(p *peer.Peer, pmes *Message) (*Message, error) {
u.DOut("handleGetValue for key: %s\n", pmes.GetKey()) u.DOut("handleGetValue for key: %s\n", pmes.GetKey())
dskey := ds.NewKey(pmes.GetKey())
// setup response
resp := &Message{ resp := &Message{
Response: true, Type: pmes.Type,
ID: pmes.GetId(), Key: pmes.Key,
Key: pmes.GetKey(),
} }
// 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.
dskey := ds.NewKey(pmes.GetKey())
iVal, err := dht.datastore.Get(dskey) iVal, err := dht.datastore.Get(dskey)
// if we got an unexpected error, bail.
if err != ds.ErrNotFound {
return nil, err
}
// if we have the value, respond with it!
if err == nil { if err == nil {
u.DOut("handleGetValue success!\n") u.DOut("handleGetValue success!\n")
resp.Success = true
resp.Value = iVal.([]byte) byts, ok := iVal.([]byte)
} else if err == ds.ErrNotFound { if !ok {
// Check if we know any providers for the requested value return nil, fmt.Errorf("datastore had non byte-slice value for %v", dskey)
}
resp.Value = byts
return resp, nil
}
// if we know any providers for the requested value, return those.
provs := dht.providers.GetProviders(u.Key(pmes.GetKey())) provs := dht.providers.GetProviders(u.Key(pmes.GetKey()))
if len(provs) > 0 { if len(provs) > 0 {
u.DOut("handleGetValue returning %d provider[s]\n", len(provs)) u.DOut("handleGetValue returning %d provider[s]\n", len(provs))
resp.Peers = provs resp.ProviderPeers = provs
resp.Success = true return resp, nil
} else { }
// No providers?
// Find closest peer on given cluster to desired key and reply with that info // Find closest peer on given cluster to desired key and reply with that info
// TODO: this should probably be decomposed.
level := 0 // stored levels are > 1, to distinguish missing levels.
if len(pmes.GetValue()) < 1 { level := pmes.GetClusterLevel()
if level < 0 {
// TODO: maybe return an error? Defaulting isnt a good idea IMO // TODO: maybe return an error? Defaulting isnt a good idea IMO
u.PErr("handleGetValue: no routing level specified, assuming 0\n") u.PErr("handleGetValue: no routing level specified, assuming 0\n")
} else { level = 0
level = int(pmes.GetValue()[0]) // Using value field to specify cluster level
} }
u.DOut("handleGetValue searching level %d clusters\n", level) u.DOut("handleGetValue searching level %d clusters\n", level)
closer := dht.routingTables[level].NearestPeer(kb.ConvertKey(u.Key(pmes.GetKey()))) ck := kb.ConvertKey(u.Key(pmes.GetKey()))
closer := dht.routingTables[level].NearestPeer(ck)
// if closer peer is self, return nil
if closer.ID.Equal(dht.self.ID) { if closer.ID.Equal(dht.self.ID) {
u.DOut("Attempted to return self! this shouldnt happen...\n") u.DOut("Attempted to return self! this shouldnt happen...\n")
resp.Peers = nil resp.CloserPeers = nil
goto out return resp, nil
} }
// If this peer is closer than the one from the table, return nil
// if self is closer than the one from the table, return nil
if kb.Closer(dht.self.ID, closer.ID, u.Key(pmes.GetKey())) { if kb.Closer(dht.self.ID, closer.ID, u.Key(pmes.GetKey())) {
resp.Peers = nil
u.DOut("handleGetValue could not find a closer node than myself.\n") u.DOut("handleGetValue could not find a closer node than myself.\n")
} else { resp.CloserPeers = nil
u.DOut("handleGetValue returning a closer peer: '%s'\n", closer.ID.Pretty()) return resp, nil
resp.Peers = []*peer.Peer{closer}
}
}
} else {
//temp: what other errors can a datastore return?
panic(err)
} }
out: // we got a closer peer, it seems. return it.
mes := swarm.NewMessage(p, resp.ToProtobuf()) u.DOut("handleGetValue returning a closer peer: '%s'\n", closer.ID.Pretty())
dht.netChan.Outgoing <- mes resp.CloserPeers = []*peer.Peer{closer}
return resp, nil
} }
// Store a value in this peer local storage // Store a value in this peer local storage
......
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