Используйте обещание в Angular 8

  private fetchData(){
    const promise = this.httpClient.get(this.apiUrl).toPromise();
    console.log(promise);  
    promise.then((data)=>{
      console.log("Promise resolved with: " + JSON.stringify(data));
    }, (error)=>{
      console.log("Promise rejected with " + JSON.stringify(error));
    })
  }
Motionless Monkey