refactor(backend): rename OpenFlare directory to lowercase openflare

backend/openflare/plugins/server/domain/fleet/websocket/relay_hub.go

@@ -0,0 +1,105 @@
+// Copyright 2026 Arctel.net
+// SPDX-License-Identifier: Apache-2.0
+
+package websocket
+
+import (
+	"log/slog"
+	"sync"
+
+	"github.com/gin-gonic/gin"
+)
+
+// RelayWSConnectedLastSeenValue is the sentinel last_seen_at value when relay WS is connected.
+const RelayWSConnectedLastSeenValue = "__OPENFLARE_WS_CONNECTED__"
+
+type relayClient struct {
+	wsClientCore
+}
+
+type relayHub struct {
+	mu      sync.RWMutex
+	clients map[string]*relayClient
+}
+
+var defaultRelayHub = &relayHub{clients: make(map[string]*relayClient)}
+
+// ServeRelay handles an upgraded relay websocket connection.
+func ServeRelay(c *gin.Context, nodeID string) {
+	conn, err := upgrader.Upgrade(c.Writer, c.Request, nil)
+	if err != nil {
+		slog.Debug("relay ws upgrade failed", "node_id", nodeID, "error", err)
+		return
+	}
+
+	client := &relayClient{
+		wsClientCore: wsClientCore{
+			nodeID: nodeID,
+			conn:   conn,
+			send:   make(chan Message, wsChannelBuf),
+			done:   make(chan struct{}),
+		},
+	}
+	defaultRelayHub.register(client)
+	defer defaultRelayHub.unregister(client)
+
+	slog.Debug("relay ws connected", "node_id", nodeID, "remote", c.Request.RemoteAddr)
+
+	go client.writePump()
+	client.readPump()
+}
+
+func (h *relayHub) register(client *relayClient) {
+	h.mu.Lock()
+	if existing := h.clients[client.nodeID]; existing != nil {
+		existing.close()
+	}
+	h.clients[client.nodeID] = client
+	h.mu.Unlock()
+}
+
+func (h *relayHub) unregister(client *relayClient) {
+	h.mu.Lock()
+	if current := h.clients[client.nodeID]; current == client {
+		delete(h.clients, client.nodeID)
+	}
+	h.mu.Unlock()
+	client.close()
+}
+
+// IsRelayConnected reports whether a relay websocket is active.
+func IsRelayConnected(nodeID string) bool {
+	defaultRelayHub.mu.RLock()
+	client := defaultRelayHub.clients[nodeID]
+	defaultRelayHub.mu.RUnlock()
+	if client == nil {
+		return false
+	}
+	select {
+	case <-client.done:
+		return false
+	default:
+		return true
+	}
+}
+
+// SendRelayPong enqueues a pong message for the relay node.
+func SendRelayPong(nodeID string) bool {
+	defaultRelayHub.mu.RLock()
+	client := defaultRelayHub.clients[nodeID]
+	defaultRelayHub.mu.RUnlock()
+	if client == nil {
+		return false
+	}
+	// 委托 enqueue：closed 检查与发送不能合并在同一个 select（两 case 同时
+	// 就绪时 Go 随机选择，close 后仍可能投递成功）。
+	return client.enqueue(Message{Type: messageTypePong})
+}
+
+func (c *relayClient) readPump() {
+	runReadPump(c.nodeID, c.conn, c.close, "relay ws", SendRelayPong, messageTypePong)
+}
+
+func (c *relayClient) writePump() {
+	runWritePump(c.nodeID, c.conn, c.done, c.send, c.close, "relay ws")
+}