feat: 实现网关服务的长连接功能

backend/gateway/internal/ws/hub.go

@@ -0,0 +1,55 @@
+package ws
+
+import (
+	"log"
+)
+
+type Hub struct {
+	// 注册的客户端
+	clients map[*Client]bool
+
+	// 从客户端接收的消息
+	broadcast chan *Message
+
+	// 注册请求
+	register chan *Client
+
+	// 注销请求
+	unregister chan *Client
+}
+
+func NewHub() *Hub {
+	return &Hub{
+		broadcast:  make(chan *Message),
+		register:   make(chan *Client),
+		unregister: make(chan *Client),
+		clients:    make(map[*Client]bool),
+	}
+}
+
+func (h *Hub) Run() {
+	for {
+		select {
+		case client := <-h.register:
+			h.clients[client] = true
+			log.Printf("Client connected. Total clients: %d", len(h.clients))
+
+		case client := <-h.unregister:
+			if _, ok := h.clients[client]; ok {
+				delete(h.clients, client)
+				close(client.send)
+				log.Printf("Client disconnected. Total clients: %d", len(h.clients))
+			}
+
+		case message := <-h.broadcast:
+			for client := range h.clients {
+				select {
+				case client.send <- message:
+				default:
+					close(client.send)
+					delete(h.clients, client)
+				}
+			}
+		}
+	}
+}