don't handle keys that aren't owned

chord/topology.go

@@ -47,9 +47,15 @@ func (n *Node) Neighbors(s []Peer) (Peer, []Peer) {
 	return n.pred, append(s, n.succ...)
 }
 
+func (n *Node) localLocked(id ID) bool {
+	return contains(n.self.id, n.succ[0].id, id)
+}
+
 // IsLocal reports whether this node owns the given key.
 func (n *Node) IsLocal(id ID) bool {
-	return contains(n.self.id, n.Successor().id, id)
+	n.mu.Lock()
+	defer n.mu.Unlock()
+	return n.localLocked(id)
 }
 
 // Closest finds the locally known peer which is the closest predecessor of key.
@@ -85,19 +91,26 @@ func (n *Node) Closest(id ID) Peer {
 	return n.self
 }
 
-// Get obtains the value for a key owned by the node.
-func (n *Node) Get(k ID) (v string, found bool) {
+// GetLocal obtains the value for a key if it is local to and owned by the node.
+func (n *Node) GetLocal(k ID) (v string, found bool) {
 	n.mu.Lock()
 	defer n.mu.Unlock()
-	v, found = n.data[k]
+	if n.localLocked(k) {
+		v, found = n.data[k]
+	}
 	return v, found
 }
 
-// Set sets the value for a key.
-func (n *Node) Set(k ID, v string) {
+// SetLocal sets the value for a key.
+// Returns false if the key is not owned by the node.
+func (n *Node) SetLocal(k ID, v string) bool {
 	n.mu.Lock()
 	defer n.mu.Unlock()
-	n.data[k] = v
+	if n.localLocked(k) {
+		n.data[k] = v
+		return true
+	}
+	return false
 }
 
 // Peer is the ID and address of a node.