add gateway token-based node registration over host:port and shared nodes manager

pkg/nodes/registry_server.go

@@ -0,0 +1,75 @@
+package nodes
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"strings"
+	"time"
+)
+
+type RegistryServer struct {
+	addr   string
+	token  string
+	mgr    *Manager
+	server *http.Server
+}
+
+func NewRegistryServer(host string, port int, token string, mgr *Manager) *RegistryServer {
+	addr := strings.TrimSpace(host)
+	if addr == "" {
+		addr = "0.0.0.0"
+	}
+	if port <= 0 {
+		port = 7788
+	}
+	return &RegistryServer{addr: fmt.Sprintf("%s:%d", addr, port), token: strings.TrimSpace(token), mgr: mgr}
+}
+
+func (s *RegistryServer) Start(ctx context.Context) error {
+	if s.mgr == nil {
+		return nil
+	}
+	mux := http.NewServeMux()
+	mux.HandleFunc("/health", func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(http.StatusOK)
+		_, _ = w.Write([]byte("ok"))
+	})
+	mux.HandleFunc("/nodes/register", s.handleRegister)
+	s.server = &http.Server{Addr: s.addr, Handler: mux}
+	go func() {
+		<-ctx.Done()
+		shutdownCtx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+		defer cancel()
+		_ = s.server.Shutdown(shutdownCtx)
+	}()
+	go func() { _ = s.server.ListenAndServe() }()
+	return nil
+}
+
+func (s *RegistryServer) handleRegister(w http.ResponseWriter, r *http.Request) {
+	if r.Method != http.MethodPost {
+		http.Error(w, "method not allowed", http.StatusMethodNotAllowed)
+		return
+	}
+	if s.token != "" {
+		auth := strings.TrimSpace(r.Header.Get("Authorization"))
+		if auth != "Bearer "+s.token {
+			http.Error(w, "unauthorized", http.StatusUnauthorized)
+			return
+		}
+	}
+	var n NodeInfo
+	if err := json.NewDecoder(r.Body).Decode(&n); err != nil {
+		http.Error(w, "invalid json", http.StatusBadRequest)
+		return
+	}
+	if strings.TrimSpace(n.ID) == "" {
+		http.Error(w, "id required", http.StatusBadRequest)
+		return
+	}
+	s.mgr.Upsert(n)
+	w.Header().Set("Content-Type", "application/json")
+	_ = json.NewEncoder(w).Encode(map[string]interface{}{"ok": true, "id": n.ID})
+}