fix: prevent stale update log polling

static/app.js

@@ -117,6 +117,10 @@ createApp({
         },
         result: null,
         pollTimer: null,
+        statusRequestInFlight: false,
+        statusRequestSeq: 0,
+        statusAppliedSeq: 0,
+        requestEpoch: 0,
       },
       restartOps: {
         loading: false,
@@ -455,7 +459,17 @@ createApp({
         return;
       }
 
+      // 轮询只保留一个在途请求，避免旧响应晚到后把新日志覆盖掉。
+      if (this.updateOps.statusRequestInFlight) {
+        return;
+      }
+
       const wasRunning = this.updateOps.running;
+      const requestSeq = this.updateOps.statusRequestSeq + 1;
+      const requestEpoch = this.updateOps.requestEpoch;
+      this.updateOps.statusRequestSeq = requestSeq;
+      this.updateOps.statusRequestInFlight = true;
+
       try {
         const query = new URLSearchParams({ id: operationId });
         const response = await fetch(`/api/ops/update-status?${query.toString()}`, { cache: "no-store" });
@@ -464,6 +478,21 @@ createApp({
           throw new Error(payload.error || `HTTP ${response.status}`);
         }
 
+        // 新任务已经开始时，直接丢掉旧任务轮询结果。
+        if (requestEpoch !== this.updateOps.requestEpoch) {
+          return;
+        }
+
+        if (this.updateOps.operationId && this.updateOps.operationId !== operationId) {
+          return;
+        }
+
+        // 保护日志顺序，旧轮询结果不能回退页面状态。
+        if (requestSeq < this.updateOps.statusAppliedSeq) {
+          return;
+        }
+        this.updateOps.statusAppliedSeq = requestSeq;
+
         this.applyUpdateOperation(payload.operation || {});
 
         if (!this.updateOps.running) {
@@ -475,6 +504,14 @@ createApp({
           }
         }
       } catch (error) {
+        if (requestEpoch !== this.updateOps.requestEpoch) {
+          return;
+        }
+
+        if (this.updateOps.operationId && this.updateOps.operationId !== operationId) {
+          return;
+        }
+
         const errorMessage = error instanceof Error ? error.message : String(error);
         const notFound = errorMessage.includes("update operation not found") || errorMessage.includes("HTTP 404");
 
@@ -499,6 +536,10 @@ createApp({
           this.updateOps.message = "更新状态查询失败";
         }
         this.updateOps.error = errorMessage;
+      } finally {
+        if (requestEpoch === this.updateOps.requestEpoch && this.updateOps.statusRequestSeq === requestSeq) {
+          this.updateOps.statusRequestInFlight = false;
+        }
       }
     },
     applyRefreshTimer() {
@@ -848,6 +889,9 @@ createApp({
       }
 
       this.stopUpdatePolling();
+      this.updateOps.requestEpoch += 1;
+      this.updateOps.statusRequestInFlight = false;
+      this.updateOps.statusAppliedSeq = 0;
       this.updateOps.running = true;
       this.updateOps.error = "";
       this.updateOps.message = "已提交更新任务，等待开始执行";