negotiate stuff

synced-pool.go

@@ -84,10 +84,8 @@ func NewSyncedPool(local *GrainLocalPool, hostname string, d Discovery) (*Synced
 				if err != nil {
 					log.Printf("Error discovering hosts: %v", err)
 				}
-				for _, h := range hosts {
-					if h == hostname {
-						continue
-					}
+				for _, h := range pool.ExcludeKnown(hosts) {
+
 					log.Printf("Discovered host %s", h)
 
 					err := pool.AddRemote(h)
@@ -115,6 +113,23 @@ func NewSyncedPool(local *GrainLocalPool, hostname string, d Discovery) (*Synced
 	return pool, nil
 }
 
+func (p *SyncedPool) ExcludeKnown(hosts []string) []string {
+	ret := make([]string, 0, len(hosts))
+	for _, h := range hosts {
+		found := false
+		for _, r := range p.remotes {
+			if r.Host == h {
+				found = true
+				break
+			}
+		}
+		if !found && h != p.Hostname {
+			ret = append(ret, h)
+		}
+	}
+	return ret
+}
+
 func (p *SyncedPool) RemoveHost(host *RemoteHost) {
 
 	for i, r := range p.remotes {
@@ -432,7 +447,9 @@ func DoPing(host *RemoteHost) error {
 }
 
 func (p *SyncedPool) addRemoteHost(address string, remote *RemoteHost) error {
+	known := make([]string, 0, len(p.remotes))
 	for _, r := range p.remotes {
+		known = append(known, r.Host)
 		if r.Host == address {
 			log.Printf("Remote %s already exists\n", address)
 			return fmt.Errorf("remote %s already exists", address)
@@ -447,7 +464,9 @@ func (p *SyncedPool) addRemoteHost(address string, remote *RemoteHost) error {
 	p.remotes = append(p.remotes, remote)
 	connectedRemotes.Set(float64(len(p.remotes)))
 	log.Printf("Added remote %s\n", remote.Host)
+
 	go func() {
+		p.Negotiate(known)
 		ids := remote.GetCartMappings()
 		p.mu.Lock()
 		for _, id := range ids {