Progressive Web Apps für Einsteiger – Hands on!

Stellen Sie sich vor, Sie schreiben Ihre moderne Businessanwendung genau einmal – und sie läuft auf Windows, macOS, Linux, Android, iOS und im Browser. Diese Anwendungen werden per Fingertippen aus dem Browser auf dem Gerät installiert, können Pushbenachrichtigungen empfangen und funktionieren auch dann, wenn das Wi-Fi im Zug gerade mal wieder nicht funktioniert. Das klingt fantastisch? Dank Progressive Web Apps (PWA) wird all das Wirklichkeit. Mit Hilfe moderner Webtechnologien wird aus einer Webanwendung eine App, die einer nativen App in nichts nachsteht. In diesem Workshop zeigt Ihnen Christian Liebel die Grundlagen der PWA-Entwicklung. Und Sie können aktiv mitentwickeln!

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1. Progressive Web Apps für Einsteiger Hands on! Christian Liebel @christianliebel Consultant
2. Hello, it’s me. Progressive Web Apps für Einsteiger Hands on! Christian Liebel Twitter: @christianliebel Email: christian.liebel @thinktecture.com Angular & PWA Slides: thinktecture.com /christian-liebel
3. Things NOT to expect - Blueprint for PWA development - No 1:1 support Things TO EXPECT - Extensive/up-to-date insights into PWA and Angular’s PWA support - A PWA use case that works on your (comparably modern) smartphone & desktop PC - Lots of fun Hands on! Progressive Web Apps für Einsteiger
4. 13:30–15:00 Block 1 15:00–15:30 Break 15:30–17:00 Block 2 Timetable Hands on! Progressive Web Apps für Einsteiger
5. Progressive Web Apps für Einsteiger Hands on! https://blogs.windows.com/windowsdeveloper/2019/11/25/developing-for-the-new-category-of-dual-screen-devices-built-for-mobile-productivity/
6. Progressive Web Apps für Einsteiger Hands on! Cross-Platform Sample https://pwapraxis.liebel.io
7. - The next best to-do list app - Create & read to-dos - Progressive Web App: installable - Responsive: one size fits all - Offline-first: synchronize to-do list with backend using IndexedDB & Dexie.js - No user context, sorry Demo Use Case Hands on! Progressive Web Apps für Einsteiger
8. Setup Node.js: https://nodejs.org (v12+) Angular CLI: npm i -g @angular/cli Google Chrome Editor Let’s get started Hands on! Progressive Web Apps für Einsteiger
9. ng new my-pwa --routing --style css cd my-pwa Angular CLI LAB #1 Hands on! Progressive Web Apps für Einsteiger
10. Hands on! Progressive Web Apps für Einsteiger Responsive Linkable Discoverable Installable App-like Connectivity Independent Fresh Safe Re-engageable Progressive
11. Platform Support PWA Status Quo Hands on! Progressive Web Apps für Einsteiger 17 11.1 44 40 4.1 Chrome 40 11.3
12. Responsive Progressive Web Apps für Einsteiger Hands on! PWA Features
13. One size fits all A single website layout for different screen resolutions (typically related to the screen’s width) Definition of trigger points at which the layout changes Mobile first: Create (minimal) mobile views first, then proceed with larger screens, so all devices get the best experience Key technologies: CSS3 Media Queries, CSS Flexible Box Layout, CSS Grid Layout Progressive Web Apps für Einsteiger Hands on! Responsive
14. Frameworks • Angular Material • ngx-admin • Bootstrap • Foundation • Framework7 • Custom-tailored solution Progressive Web Apps für Einsteiger Hands on! Responsive
15. ng add @angular/material Responsive LAB #2 Hands on! Progressive Web Apps für Einsteiger
16. Linkable Progressive Web Apps für Einsteiger Hands on! PWA Features
17. Reference Apps and Internal App States Goal: Directly link to applications or application states/views (deep link) Key technology for references in the World Wide Web: Hyperlinks Schema for hyperlinks: Uniform Resource Locator (URL) Solved in Angular via Routing (for views and states) Linkable Hands on! Progressive Web Apps für Einsteiger
18. ng g c todos ng g c about <router-outlet> Linkable LAB #3 Hands on! Progressive Web Apps für Einsteiger
19. Discoverable Progressive Web Apps für Einsteiger Hands on! PWA Features
20. Distinguish Web Apps from Websites How to distinguish websites from apps? Idea: Add a file with metadata for apps only Advantage: Apps can be identified by search engines, app store providers etc. Web App Manifest <link rel="manifest" href="manifest.webmanifest"> Discoverable Hands on! Progressive Web Apps für Einsteiger
21. manifest.webmanifest { "short_name": "PWA Demo", "name": "My PWA Demo", "icons": [ { "src": "assets/icon-144x144.png", "sizes": "144x144", "type": "image/png" } ], "start_url": "/index.html", "display": "standalone" } Web App Manifest Title Icons Start URL Display Type Age Rating Additional Config Description Related Apps Hands on! Progressive Web Apps für Einsteiger
22. manifest.webmanifest { "short_name": "PWA Demo", "name": "My PWA Demo", "icons": [ { "src": "assets/icon-144x144.png", "sizes": "144x144", "type": "image/png" } ], "start_url": "/index.html", "display": "standalone" } Web App Manifest Hands on! Progressive Web Apps für Einsteiger
23. Angular CLI & PWA Schematic ng add @angular/pwa Web App Manifest LAB #4 Hands on! Progressive Web Apps für Einsteiger
24. Shortcuts Progressive Web Apps für Einsteiger Hands on! Web App Manifest
25. Badging API Progressive Web Apps für Einsteiger Hands on! Web App Manifest
26. Installable Progressive Web Apps für Einsteiger Hands on! PWA Features
27. manifest.webmanifest { "short_name": "PWA Demo", "name": "My PWA Demo", "icons": [ { "src": "assets/icon-144x144.png", "sizes": "144x144", "type": "image/png" } ], "start_url": "/index.html", "display": "standalone" } App Install Banner Hands on! Progressive Web Apps für Einsteiger
28. Progressive Web Apps für Einsteiger Hands on!
29. Progressive Web Apps für Einsteiger Hands on! Installable
30. Web App Manifest Adjust the Web App Manifest (manifest.webmanifest) to your needs Run ng build Test it by adding the app to your home screen Installable LAB #5 Hands on! Progressive Web Apps für Einsteiger
31. App-Like Progressive Web Apps für Einsteiger Hands on! PWA Features
32. The Power of the Modern Web Web Share API Gamepad API Payment Request API Generic Sensor API Web Bluetooth API Shape Detection API Web Notifications WebXR WebRTC WebGL Speech Synthesis Web Cryptography API IndexedDB Geolocation Canvas Media Capture and Streams Hands on! Progressive Web Apps für Einsteiger
33. Native look & feel Progressive Web Apps für Einsteiger Hands on! App-like
34. cd ../.. ng generate @angular/material:nav nav Progressive Web Apps für Einsteiger Hands on! Generate Navigation LAB #6
35. Connectivity Independent Part 1 Progressive Web Apps für Einsteiger Hands on! PWA Features
36. Progressive Web Apps für Einsteiger Hands on! Offline capability with Service Worker System Website HTML/JS Cache Storage Remote storage Server Internet fetch HTTP Service Worker
37. Overview Implements a “one-size-fits-all” service worker Instrumented via ngsw-config.json Restricted feature set (e.g., no communication between app and SW) • Initial caching of static content • Caching external content • Dynamic Caching • Push notifications @angular/service-worker Hands on! Progressive Web Apps für Einsteiger
38. Debugging More information on installed service workers can be found on • chrome://serviceworker- internals (Google Chrome) • about:serviceworkers (Mozilla Firefox) Progressive Web Apps für Einsteiger Hands on! Service Worker
39. Debugging Debug Service Workers using Chrome Developer Tools Progressive Web Apps für Einsteiger Hands on! Service Worker LAB #7
40. Fresh Progressive Web Apps für Einsteiger Hands on! PWA Features
41. Keep your app up-to-date The Service Worker caches a specific version of your application. If the user is online, you want to deliver the latest version of your app. When new versions become available, you might want to notify the user to update the application. Progressive Web Apps für Einsteiger Hands on! Fresh
42. @angular/service-worker Update Process Progressive Web Apps für Einsteiger Hands on! Fresh V1 V2 V2 V1 V1 V2 Server Browser
43. SwUpdate @angular/service-worker offers an SwUpdate service This service provides an available observable that fires when there’s an update. As a result, the user can be prompted to reload the website. Progressive Web Apps für Einsteiger Hands on! Fresh
44. App-like, Connectivity Independent, Fresh Check for application updates swUpdate.available.subscribe(() => …); Progressive Web Apps für Einsteiger Hands on! Fresh LAB #8
45. Connectivity Independent Part 2 Progressive Web Apps für Einsteiger Hands on! PWA Features
46. Orthogonal to Service Workers The web platform has different techniques to store arbitrary data (e.g. application state) offline: • Web Storage API (Local Storage/Session Storage—synchronous!) • Cookies (inconvenient) • IndexedDB Progressive Web Apps für Einsteiger Hands on! Offline Capability
47. IndexedDB Progressive Web Apps für Einsteiger Hands on! Offline Capability
48. IndexedDB let db; const request = indexedDB. open('TestDB'); request.onerror = err => { console.error('boo!'); }; request.onsuccess = evt => { db = request.result; }; IndexedDB API is inconvenient const db = new Dexie('TestDB'); Progressive Web Apps für Einsteiger Hands on! Offline Capability
49. Dexie.js Dexie is a minimalistic wrapper for IndexedDB Operations are based on promises instead of callbacks Near native performance (also for bulk inserts) Open-source Progressive Web Apps für Einsteiger Hands on! Offline Capability
50. IndexedDB Model { "id": "2db0d3e5-…", "title": "Angular lernen", "done": false } Install packages npm i dexie uuid @types/uuid --save-dev Dexie.js Table API Implement a TodoService with getAll & add methods Progressive Web Apps für Einsteiger Hands on! Offline Capability LAB #9
51. Safe Progressive Web Apps für Einsteiger Hands on! PWA Features
52. PWAs Require HTTPS! Service workers are very powerful • Can answer representatively for the server • Runs outside of the tab’s/window’s lifecycle Installation of service workers is only allowed via a secure connection Exception: localhost (for development purposes) PWAs can only be delivered via HTTPS Problem: TLS certificates are required (costs/renewal) Safe Hands on! Progressive Web Apps für Einsteiger
53. Free with automatic renewal Initiative of the Linux Foundation Automatic domain validation (Class 1) Website/Webservice has to be public available Period of validity: Comparatively short (90 days) Usage of TLS/SSL as easy as possible Plugins are available for IIS, Apache, Microsoft Azure, Plesk, … free! Let’s Encrypt Hands on! Progressive Web Apps für Einsteiger
54. Re-engageable Progressive Web Apps für Einsteiger Hands on! PWA Features
55. Get the user back with notifications Progressive Web Apps für Einsteiger Hands on! Re-Engageable Ä Peter and 12 other people like your photo. SOCIAL NETWORK 08:12 Only today! 350 golden diamonds 💎 for $3.49!! PAY TO WIN GAME 11:19
56. Push API Progressive Web Apps für Einsteiger Hands on! Re-Engageable 17 — 44 44
57. Limitations Not supported by Apple Safari on desktop and mobile - Safari Push Notfications: an alternative for the desktop platform - No information on whether or when push will be supported BUT: You can make a difference! Let the WebKit team know what you want to build with Push API: https://liebel.io/pushbug Progressive Web Apps für Einsteiger Hands on! Re-Engageable
58. Progressive Progressive Web Apps für Einsteiger Hands on! PWA Features
59. Advance with Progressive Enhancement Idea: Use available interfaces and functions of a system Users with modern, feature-rich browsers are getting better experience Apps are available on older browsers but with limited functionality Concept: Browser feature support grows over time—thereby more users can enjoy an increasing number of app features Progressive Web Apps für Einsteiger Hands on! Progressive
60. Progressive Web Apps für Einsteiger Hands on!
61. Progressive Web Apps für Einsteiger Hands on! PWAs & App Stores (US)
62. Native App Packaging Hands on! Progressive Web Apps für Einsteiger JS HTML CSS .ipa .exe .app ELF .apk .appx Single-Page Application Cordova Electron
63. Progressive Web Apps für Einsteiger Hands on! Where’s the Web Heading to?
64. Thank you for your kind attention! Christian Liebel @christianliebel christian.liebel@thinktecture.com