Route Resolvers in Angular 7

hn.resolver.ts

import { Injectable } from '@angular/core';
import { HnService } from './hn.service';

import { Resolve } from '@angular/router';

import { ActivatedRouteSnapshot } from '@angular/router';

@Injectable()
export class HnResolver implements Resolve<any> {
  constructor(private hnService: HnService) {}

  resolve(route: ActivatedRouteSnapshot) {
    return this.hnService.getPost(route.paramMap.get('id'));
  }
}

hn.service.ts

getPost(postId: string) {
  const endpoint = 'https://hnpwa.com/api/v0/item';

  return this.http.get(`${endpoint}/${postId}.json`);
}

test.route.ts

{
  path: 'post/:id',
  component: PostComponent,
  resolve: { hnData: HnResolver }
}