Improve message receive time accuracy

backend/src/Model/ChangeBuffer.ts

@@ -1,7 +1,12 @@
 import { MqttMessage } from '../../../events'
 
+interface BufferedMessage {
+  message: MqttMessage
+  received: Date
+}
+
 export class ChangeBuffer {
-  private buffer: Array<MqttMessage> = []
+  private buffer: Array<BufferedMessage> = []
   private size = 0
   private maxSize = 100_000_000 // ~100MB
   public length = 0
@@ -9,7 +14,7 @@ export class ChangeBuffer {
 
   public push(val: MqttMessage) {
     if (!this.isFull()) {
-      this.buffer.push(val)
+      this.buffer.push({ message: val, received: new Date() })
       this.size += this.estimatedMessageOverhead + (val.payload ? val.payload.length : 0)
       this.length += 1
     }
@@ -27,7 +32,7 @@ export class ChangeBuffer {
     return this.size / this.maxSize
   }
 
-  public popAll(): Array<MqttMessage> {
+  public popAll(): Array<BufferedMessage> {
     const tmpBuffer = this.buffer
     this.buffer = []
     this.size = 0

backend/src/Model/Tree.ts

@@ -48,10 +48,14 @@ export class Tree<ViewModel extends Destroyable> extends TreeNode<ViewModel> {
   }
 
   public applyUnmergedChanges() {
-    this.unmergedMessages.popAll().forEach(msg => {
-      const edges = msg.topic.split('/')
-      const node = TreeNodeFactory.fromEdgesAndValue<ViewModel>(edges, msg.payload)
-      node.mqttMessage = msg
+    this.unmergedMessages.popAll().forEach(bufferedItem => {
+      const edges = bufferedItem.message.topic.split('/')
+      const node = TreeNodeFactory.fromEdgesAndValue<ViewModel>(
+        edges,
+        bufferedItem.message.payload,
+        bufferedItem.received
+      )
+      node.mqttMessage = bufferedItem.message
 
       if (!this.nodeFilter || this.nodeFilter(node)) {
         this.updateWithNode(node.firstNode())

backend/src/Model/TreeNodeFactory.ts

@@ -22,13 +22,14 @@ export abstract class TreeNodeFactory {
 
   public static fromEdgesAndValue<ViewModel extends Destroyable>(
     edgeNames: Array<string>,
-    value?: Base64Message | null
+    value?: Base64Message | null,
+    receiveDate: Date = new Date()
   ): TreeNode<ViewModel> {
     const node = new TreeNode<ViewModel>()
     node.setMessage({
       value: value || undefined,
       length: value ? value.length : 0,
-      received: new Date(),
+      received: receiveDate,
       messageNumber: this.messageCounter,
     })
     this.messageCounter += 1