app.component.ts

import { Component, OnInit } from "@angular/core";

@Component({
  selector: "app",
  templateUrl: "./app.component.html",
  styleUrls: ["./app.component.scss"]
})
export class AppComponent implements OnInit {
  public ngOnInit() {
    if ("serviceWorker" in navigator) {
      navigator.serviceWorker
        .register("./sw.js")
        .then(registration => {
          console.log(
            "ServiceWorker registration successful with scope: ",
            registration.scope
          );
        })
        .catch(err => {
          console.log("ServiceWorker registration failed: ", err);
        });
    }
  }
}