Ionic v4 pwa example for `beta.15`

I’m trying to add pwa to an existing project but it doesn’t seem to work. I’ve also tried to add to a new project, but it doesn’t seem to follow the script for the Howtos online. Can anyone point to a working example?

Here’s how I started a new project:

ionic start ionic4-pwa blank --type=angular; cd ./ionic4-pwa
ng add @angular/pwa --project app

from this tutorial, https://www.joshmorony.com/create-a-pwa-with-angular-service-workers-in-ionic-4/, I’m expecting to find a file, ngsw-config.json, but… nothing.

here’s my package.json:

{
  "name": "ionic4-pwa",
  "version": "0.0.1",
  "author": "Ionic Framework",
  "homepage": "http://ionicframework.com/",
  "scripts": {
    "ng": "ng",
    "start": "ng serve",
    "build": "ng build",
    "test": "ng test",
    "lint": "ng lint",
    "e2e": "ng e2e"
  },
  "private": true,
  "dependencies": {
    "@angular/common": "~6.1.1",
    "@angular/core": "~6.1.1",
    "@angular/forms": "~6.1.1",
    "@angular/http": "~6.1.1",
    "@angular/platform-browser": "~6.1.1",
    "@angular/platform-browser-dynamic": "~6.1.1",
    "@angular/pwa": "^0.10.5",
    "@angular/router": "~6.1.1",
    "@ionic-native/core": "5.0.0-beta.21",
    "@ionic-native/splash-screen": "5.0.0-beta.21",
    "@ionic-native/status-bar": "5.0.0-beta.21",
    "@ionic/angular": "4.0.0-beta.15",
    "core-js": "^2.5.3",
    "rxjs": "6.2.2",
    "zone.js": "^0.8.26"
  },
  "devDependencies": {
    "@angular-devkit/architect": "~0.8.5",
    "@angular-devkit/build-angular": "~0.8.5",
    "@angular-devkit/core": "~0.8.5",
    "@angular-devkit/schematics": "~0.8.5",
    "@angular/cli": "~6.2.5",
    "@angular/compiler": "~6.1.1",
    "@angular/compiler-cli": "~6.1.1",
    "@angular/language-service": "~6.1.1",
    "@ionic/angular-toolkit": "^1.0.0",
    "@types/jasmine": "~2.8.6",
    "@types/jasminewd2": "~2.0.3",
    "@types/node": "~10.12.0",
    "codelyzer": "~4.5.0",
    "jasmine-core": "~2.99.1",
    "jasmine-spec-reporter": "~4.2.1",
    "karma": "~3.0.0",
    "karma-chrome-launcher": "~2.2.0",
    "karma-coverage-istanbul-reporter": "~2.0.0",
    "karma-jasmine": "~1.1.1",
    "karma-jasmine-html-reporter": "^0.2.2",
    "protractor": "~5.4.0",
    "ts-node": "~7.0.0",
    "tslint": "~5.11.0",
    "typescript": "~2.9.2"
  },
  "description": "An Ionic project"
}

Ionic:

   ionic (Ionic CLI)             : 4.3.1 (/Users/m/.nvm/versions/node/v8.9.4/lib/node_modules/ionic)
   Ionic Framework               : @ionic/angular 4.0.0-beta.15
   @angular-devkit/build-angular : 0.8.7
   @angular-devkit/schematics    : 0.8.7
   @angular/cli                  : 6.2.7
   @ionic/angular-toolkit        : 1.1.0

System:

   NodeJS : v8.9.4 (/Users/m/.nvm/versions/node/v8.9.4/bin/node)
   npm    : 6.4.1
   OS     : macOS High Sierra

wait… it seems that I need this

npm install @angular/cli@^7.0 --save-dev;