chore: sync local updates

mengyamonitor-backend-server/internal/handler/ws.go

@@ -0,0 +1,50 @@
+package handler
+
+import (
+	"log"
+	"net/http"
+	"time"
+
+	"mengyamonitor-backend-server/internal/hub"
+
+	"github.com/gin-gonic/gin"
+	"github.com/gorilla/websocket"
+)
+
+var wsUpgrader = websocket.Upgrader{
+	ReadBufferSize:  1024,
+	WriteBufferSize: 1024,
+	CheckOrigin: func(r *http.Request) bool {
+		return true
+	},
+}
+
+// MonitorWebSocket upgrades to WebSocket and streams hub snapshots.
+func MonitorWebSocket(h *hub.Hub) gin.HandlerFunc {
+	return func(c *gin.Context) {
+		conn, err := wsUpgrader.Upgrade(c.Writer, c.Request, nil)
+		if err != nil {
+			log.Printf("ws: upgrade: %v", err)
+			return
+		}
+		defer h.Unregister(conn)
+		snap, err := h.BuildSnapshotMessage()
+		if err != nil {
+			_ = conn.Close()
+			return
+		}
+		_ = conn.SetWriteDeadline(time.Now().Add(15 * time.Second))
+		if err := conn.WriteMessage(websocket.TextMessage, snap); err != nil {
+			_ = conn.Close()
+			return
+		}
+		h.AddSubscriber(conn)
+		for {
+			_ = conn.SetReadDeadline(time.Now().Add(120 * time.Second))
+			_, _, err := conn.ReadMessage()
+			if err != nil {
+				break
+			}
+		}
+	}
+}