Getting empty json data

I'm trying to get json data from the url, but i'm not able to get any. It is just showing an empty array. What do you think that I'm missing here?

service.ts

this is the service.ts. Im trying to get data from 'https://jsonplaceholder.typicode.com/posts'.

import { Injectable } from '@angular/core';
import{UserCreation} from '../../models/user-creation.model';
import{Observable} from 'rxjs/Observable';
import{of} from 'rxjs/observable/of';
import{catchError,map,tap} from 'rxjs/operators';
import{HttpClient,HttpHeaders} from '@angular/common/http';

const httpOptions={
    headers:new HttpHeaders({'Content-Type':'application/json'})
};

@Injectable({
providedIn: 'root'
})

export class UserCreationService{

//Create constructor to get Http instance
constructor(private http:HttpClient) { }

private usersUrl:'https://jsonplaceholder.typicode.com/posts';

getUsers():Observable<UserCreation[]>{

return this.http.get<UserCreation[]>(this.usersUrl).pipe(
tap(receivedUsers 
=>console.log(`receivedUsers=${JSON.stringify(receivedUsers)}`)),
catchError(error=>of([]))
);
}

app.component.ts

this is the component.ts file

import { Component, OnInit } from '@angular/core';
import { Http, Response } from '@angular/http';
import { UserCreationService } from '../../common/services/user- 
creation.service';


@Component({
selector: 'app',
templateUrl: './app.component.html',
styleUrls: ['./app-component.css']
})

export class AppComponent implements OnInit {

allUsers: UserCreation[];

constructor(private userService: UserCreationService) { }

getUsersFromServices():void{
this.userService.getUsers().subscribe(
  (Users)=>{
    this.allUsers=Users;
    console.log(`this.allUsers = ${JSON.stringify(this.allUsers)}`);

  }
 )
}

ngOnInit(): void {
this.getUsersFromServices();
}