Angular Websocket service with wait for response sending

Question

I am writing an Angular Websocket service that can send messages to a server and then can subscribe to the response. I am grateful for every suggestion to improve this.

import { Injectable, OnDestroy } from '@angular/core';
import {webSocket, WebSocketSubject} from "rxjs/webSocket";
import {of, from, Observable, timer, BehaviorSubject, pipe, EMPTY} from "rxjs";
import {share, filter, timeout, switchMap, take, catchError, mergeMap} from "rxjs/operators";

export class WsMessage{
  Id: number;
  TimeStamp: Date;
  ResponseId: number;
  MessageData: string;
}

class MessageQueue{
  Message: WsMessage;
  TimeStamp: Date;
  SyncId: number;
}

@Injectable({  providedIn: 'root'})
export class WebSocketServiceService implements OnDestroy {
  // Each message has a maximum lifetime of 10 mimnutes.
  private readonly MaxMessageQueueTime = 600;
  private clearQueueTimer: any;
  private messageQueue: Array<MessageQueue> = new Array<MessageQueue>(); 
  private socket: WebSocketSubject<WsMessage>;
  private idGenerator: number;

  private messageReceiver = new BehaviorSubject<WsMessage>(null);
  public OnMessages: Observable<WsMessage>;

  constructor(){
    this.OnMessages = this.messageReceiver.asObservable();
      // Check every 30s for clearing old messages.
    this.clearQueueTimer = setInterval(() =>{
      if(this.messageQueue){
        let maxTime = new Date();
        maxTime = new Date(maxTime.setTime(maxTime.getTime() + 
        (this.MaxMessageQueueTime * 1000)));
        this.messageQueue= this.messageQueue.filter(m => m.TimeStamp <= maxTime);
      }
    }, 30000);
  }


  public Init(url: string){
      this.idGenerator = 0;
      if(this.socket!= null) {
        this.socket.unsubscribe();
        this.socket = null;
      }
      this.socket = webSocket<WsMessage>({
        url: url,
        openObserver: {
          next: value => {
            console.log(value);
          }
        }
      });
      this.socket.subscribe(msg => {
        if(msg != null && msg.ResponseId > 0){
          let m = new MessageQueue();
          m.SyncId = msg.Id;
          m.Message = msg;
          m.TimeStamp = new Date();  
          this.messageQueue.push(m);                      
        }
        this.messageReceiver.next(msg);
        console.log("msg received: " + msg);
      },
      error1 => {
        console.log("error received: " + error1);
      },
      () => {
        console.log("connection closed!");
      });    
    }

    public sendAndWait(msg: WsMessage, wait: number): Observable<WsMessage>{
      if(msg == null){
        return null;
      }
    let id = this.idGenerator++;
    msg.Id = id;
    if(this.socket == null){
      return null;
    }
    this.socket.next(msg);
    let result = this.OnMessages.pipe(
      filter(p => p.Id == id),
      take(1),
      timeout(wait),
      catchError((error) => {
        console.log("timeout: " + error);
        return EMPTY;
      })).pipe(share());

    result.pipe(untilDestroyed(this)).subscribe(value => {
      if(value != null) {
        this.messageQueue.splice(this.messageQueue.findIndex(i => i.SyncId == id), 1);
      }
    });
    return result;
  }

  ngOnDestroy(): void {
    clearInterval(this.clearQueueTimer);
    if(this.socket != null) {
      this.socket.unsubscribe();
    }    
  }
}