From 6b475fbd01660a6adb8458a395d25a6278b8a862 Mon Sep 17 00:00:00 2001
From: ababak <artemio.babak@gmail.com>
Date: Fri, 3 Apr 2026 17:18:24 +0300
Subject: [PATCH 1/3] Clear pending updates on socket close and process them on
 reconnect. Add `syncCommandId` method to align subscriptions with existing
 commands.

---
 .../app/core/ws/telemetry-websocket.service.ts    | 15 +++++++++++++++
 ui-ngx/src/app/core/ws/websocket.service.ts       | 12 ++++++++++++
 2 files changed, 27 insertions(+)

diff --git a/ui-ngx/src/app/core/ws/telemetry-websocket.service.ts b/ui-ngx/src/app/core/ws/telemetry-websocket.service.ts
index ddf5018a69..2d7c8af529 100644
--- a/ui-ngx/src/app/core/ws/telemetry-websocket.service.ts
+++ b/ui-ngx/src/app/core/ws/telemetry-websocket.service.ts
@@ -50,6 +50,7 @@ import {
   UnreadCountSubCmd,
   UnreadSubCmd,
   UnsubscribeCmd,
+  WebsocketCmd,
   WebsocketDataMsg
 } from '@app/shared/models/telemetry/telemetry.models';
 import { Store } from '@ngrx/store';
@@ -94,11 +95,14 @@ export class TelemetryWebsocketService extends WebsocketService<TelemetrySubscri
       subscriber.subscriptionCommands.forEach(
         (subscriptionCommand) => {
           if (subscriptionCommand.cmdId && (subscriptionCommand instanceof EntityDataCmd || subscriptionCommand instanceof UnreadSubCmd)) {
+            this.syncCommandId(subscriptionCommand, subscriber);
             this.cmdWrapper.cmds.push(subscriptionCommand);
           }
         }
       );
       this.publishCommands();
+    } else {
+      this.pendingUpdates.add(subscriber);
     }
   }
 
@@ -177,4 +181,15 @@ export class TelemetryWebsocketService extends WebsocketService<TelemetrySubscri
     }
   }
 
+  private syncCommandId(subscriptionCommand: WebsocketCmd, subscriber: TelemetrySubscriber) {
+    if (!this.subscribersMap.has(subscriptionCommand.cmdId)) {
+      for (const [cmdId, sub] of this.subscribersMap.entries()) {
+        if (sub === subscriber) {
+          subscriptionCommand.cmdId = cmdId;
+          break;
+        }
+      }
+    }
+  }
+
 }
diff --git a/ui-ngx/src/app/core/ws/websocket.service.ts b/ui-ngx/src/app/core/ws/websocket.service.ts
index 2d7da5ae67..b94caa04c8 100644
--- a/ui-ngx/src/app/core/ws/websocket.service.ts
+++ b/ui-ngx/src/app/core/ws/websocket.service.ts
@@ -52,6 +52,7 @@ export abstract class WebsocketService<T extends WsSubscriber> implements WsServ
   subscribersMap = new Map<number, TelemetrySubscriber | NotificationSubscriber>();
 
   reconnectSubscribers = new Set<WsSubscriber>();
+  pendingUpdates = new Set<T>();
 
   wsUri: string;
 
@@ -140,6 +141,7 @@ export abstract class WebsocketService<T extends WsSubscriber> implements WsServ
     if (close) {
       this.reconnectAttempts = 0;
       this.lastShownCloseCode = null;
+      this.pendingUpdates.clear();
       this.closeSocket();
     }
   }
@@ -223,6 +225,7 @@ export abstract class WebsocketService<T extends WsSubscriber> implements WsServ
         }
       );
       this.reconnectSubscribers.clear();
+      this.processPendingUpdates();
     } else {
       this.publishCommands();
     }
@@ -298,4 +301,13 @@ export abstract class WebsocketService<T extends WsSubscriber> implements WsServ
       message, type: notificationType
     }));
   }
+
+  private processPendingUpdates() {
+    if (this.pendingUpdates.size > 0) {
+      this.pendingUpdates.forEach((subscriber) => {
+        this.update(subscriber);
+      });
+      this.pendingUpdates.clear();
+    }
+  }
 }

From 3bd5d424e72f707edd3e3863ea679c97ba4ea822 Mon Sep 17 00:00:00 2001
From: ababak <artemio.babak@gmail.com>
Date: Tue, 7 Apr 2026 17:45:48 +0300
Subject: [PATCH 2/3] fix: add subscriberCmdIds reverse index and defensive
 guard in processPendingUpdates

---
 .../core/ws/telemetry-websocket.service.ts    | 21 ++++++++++++++-----
 ui-ngx/src/app/core/ws/websocket.service.ts   | 11 +++++++---
 2 files changed, 24 insertions(+), 8 deletions(-)

diff --git a/ui-ngx/src/app/core/ws/telemetry-websocket.service.ts b/ui-ngx/src/app/core/ws/telemetry-websocket.service.ts
index 2d7c8af529..fbe69d55ae 100644
--- a/ui-ngx/src/app/core/ws/telemetry-websocket.service.ts
+++ b/ui-ngx/src/app/core/ws/telemetry-websocket.service.ts
@@ -81,6 +81,12 @@ export class TelemetryWebsocketService extends WebsocketService<TelemetrySubscri
         const cmdId = this.nextCmdId();
         if (!(subscriptionCommand instanceof MarkAsReadCmd) && !(subscriptionCommand instanceof MarkAllAsReadCmd)) {
           this.subscribersMap.set(cmdId, subscriber);
+          let cmdIds = this.subscriberCmdIds.get(subscriber);
+          if (!cmdIds) {
+            cmdIds = new Set<number>();
+            this.subscriberCmdIds.set(subscriber, cmdIds);
+          }
+          cmdIds.add(cmdId);
         }
         subscriptionCommand.cmdId = cmdId;
         this.cmdWrapper.cmds.push(subscriptionCommand);
@@ -141,6 +147,13 @@ export class TelemetryWebsocketService extends WebsocketService<TelemetrySubscri
           const cmdId = subscriptionCommand.cmdId;
           if (cmdId) {
             this.subscribersMap.delete(cmdId);
+            const cmdIds = this.subscriberCmdIds.get(subscriber);
+            if (cmdIds) {
+              cmdIds.delete(cmdId);
+              if (cmdIds.size === 0) {
+                this.subscriberCmdIds.delete(subscriber);
+              }
+            }
           }
         }
       );
@@ -183,11 +196,9 @@ export class TelemetryWebsocketService extends WebsocketService<TelemetrySubscri
 
   private syncCommandId(subscriptionCommand: WebsocketCmd, subscriber: TelemetrySubscriber) {
     if (!this.subscribersMap.has(subscriptionCommand.cmdId)) {
-      for (const [cmdId, sub] of this.subscribersMap.entries()) {
-        if (sub === subscriber) {
-          subscriptionCommand.cmdId = cmdId;
-          break;
-        }
+      const cmdIds = this.subscriberCmdIds.get(subscriber);
+      if (cmdIds?.size) {
+        subscriptionCommand.cmdId = cmdIds.values().next().value;
       }
     }
   }
diff --git a/ui-ngx/src/app/core/ws/websocket.service.ts b/ui-ngx/src/app/core/ws/websocket.service.ts
index b94caa04c8..7b8c488082 100644
--- a/ui-ngx/src/app/core/ws/websocket.service.ts
+++ b/ui-ngx/src/app/core/ws/websocket.service.ts
@@ -50,6 +50,7 @@ export abstract class WebsocketService<T extends WsSubscriber> implements WsServ
   lastCmdId = 0;
   subscribersCount = 0;
   subscribersMap = new Map<number, TelemetrySubscriber | NotificationSubscriber>();
+  subscriberCmdIds = new Map<WsSubscriber, Set<number>>();
 
   reconnectSubscribers = new Set<WsSubscriber>();
   pendingUpdates = new Set<T>();
@@ -136,6 +137,7 @@ export abstract class WebsocketService<T extends WsSubscriber> implements WsServ
     }
     this.lastCmdId = 0;
     this.subscribersMap.clear();
+    this.subscriberCmdIds.clear();
     this.subscribersCount = 0;
     this.cmdWrapper.clear();
     if (close) {
@@ -304,10 +306,13 @@ export abstract class WebsocketService<T extends WsSubscriber> implements WsServ
 
   private processPendingUpdates() {
     if (this.pendingUpdates.size > 0) {
-      this.pendingUpdates.forEach((subscriber) => {
-        this.update(subscriber);
-      });
+      const subscribers = Array.from(this.pendingUpdates);
       this.pendingUpdates.clear();
+      for (const subscriber of subscribers) {
+        if (this.subscriberCmdIds.has(subscriber)) {
+          this.update(subscriber);
+        }
+      }
     }
   }
 }

From da340fa5549197e32b4ea9395d2a3dfafe725d58 Mon Sep 17 00:00:00 2001
From: ababak <artemio.babak@gmail.com>
Date: Wed, 8 Apr 2026 11:28:38 +0300
Subject: [PATCH 3/3] fix: check cmdId ownership instead of existence in
 syncCommandId

---
 ui-ngx/src/app/core/ws/telemetry-websocket.service.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/ui-ngx/src/app/core/ws/telemetry-websocket.service.ts b/ui-ngx/src/app/core/ws/telemetry-websocket.service.ts
index fbe69d55ae..bc63938775 100644
--- a/ui-ngx/src/app/core/ws/telemetry-websocket.service.ts
+++ b/ui-ngx/src/app/core/ws/telemetry-websocket.service.ts
@@ -195,7 +195,7 @@ export class TelemetryWebsocketService extends WebsocketService<TelemetrySubscri
   }
 
   private syncCommandId(subscriptionCommand: WebsocketCmd, subscriber: TelemetrySubscriber) {
-    if (!this.subscribersMap.has(subscriptionCommand.cmdId)) {
+    if (this.subscribersMap.get(subscriptionCommand.cmdId) !== subscriber) {
       const cmdIds = this.subscriberCmdIds.get(subscriber);
       if (cmdIds?.size) {
         subscriptionCommand.cmdId = cmdIds.values().next().value;