finish node server

chord/httpnode/server.go

@@ -43,6 +43,7 @@ func (n *Node) Router() http.Handler {
 	m := http.NewServeMux()
 	m.HandleFunc("GET /succ", n.successor)
 	m.HandleFunc("POST /pred", n.notify)
+	m.HandleFunc("GET /neighbors", n.neighbors)
 	return m
 }
 
@@ -63,7 +64,6 @@ func (n *Node) successor(w http.ResponseWriter, r *http.Request) {
 }
 
 func (n *Node) notify(w http.ResponseWriter, r *http.Request) {
-	// Another node is telling us they think they're our predecessor.
 	s := r.FormValue("p")
 	addr, err := netip.ParseAddrPort(s)
 	if err != nil {
@@ -72,4 +72,19 @@ func (n *Node) notify(w http.ResponseWriter, r *http.Request) {
 	}
 	np := chord.Address(addr)
 	chord.Notify(n.self, np)
+	w.WriteHeader(http.StatusNoContent)
+}
+
+func (n *Node) neighbors(w http.ResponseWriter, r *http.Request) {
+	pred, succ := n.self.Neighbors(nil)
+	_, paddr := pred.Values()
+	u := neighbors{
+		Succ: make([]netip.AddrPort, 0, len(succ)),
+		Pred: paddr,
+	}
+	for _, s := range succ {
+		_, addr := s.Values()
+		u.Succ = append(u.Succ, addr)
+	}
+	writeOk(w, &u)
 }