WordPressをプラグインなしでPWA化してみた

{
    "name": "オンライン将棋教室　香",
    "short_name": "オン香",
    "icons": [
        {
            "src": "【512x512のアイコン画像がアップロードされているパス】",
            "type": "image/png",
            "sizes": "512x512"
        },
        {
            "src": "【192x192のアイコン画像がアップロードされているパス】",
            "type": "image/png",
            "sizes": "192x192"
        }
    ],
    "start_url": "/?source=pwa",
    "scope": "/",
    "display": "fullscreen",
    "background_color": "#f6cc82",
    "description": "自宅で、気軽に、公認の将棋指導員の、マンツーマンレッスンが受けられる、インターネット上の将棋教室です。",
    "theme_color": "#f6cc82",
    "orientation": "any"
}

const CACHE_NAME = '2022-04-01';
const OFFLINE_URL = 'https://xn--eckl3qmbc2cv902cnwa746d81h183l.com/';
const urlsToCache = ['https://xn--eckl3qmbc2cv902cnwa746d81h183l.com/'];
const neverCacheUrls = /\/wp-admin|\/wp-login|preview=true|\/cart|ajax|login/;
 
self.addEventListener('install', (event) => {
	event.waitUntil(
		caches.open(CACHE_NAME).then((cache) => {
			return cache.addAll(urlsToCache);
		})
	);
});
 
self.addEventListener('activate', (event) => {
	event.waitUntil(
		caches
			.keys()
			.then((keys) =>
				Promise.all(
					keys.map((key) => {
						if (CACHE_NAME !== key) {
							return caches.delete(key);
						}
					})
				)
			)
			.then(() => {
				self.clients.claim();
			})
	);
});
 
self.addEventListener('fetch', (e) => {
	if (!e.request.url.match(/^(http|https):\/\//i)) {
		return;
	}
 
	if (new URL(e.request.url).origin !== location.origin) {
		return;
	}
 
	if (neverCacheUrls.test(e.request.url)) {
		return;
	}
	if (neverCacheUrls.test(e.request.referrer)) {
		return;
	}
 
	if (e.request.referrer.match(/^(wp-admin):\/\//i)) {
		return;
	}
 
	if (e.request.method !== 'GET') {
		e.respondWith(
			fetch(e.request).catch(() => {
				return caches.match(OFFLINE_URL);
			})
		);
		return;
	}
 
	if (e.request.mode === 'navigate' && navigator.onLine) {
		e.respondWith(
			fetch(e.request).then((response) => {
				return caches.open(CACHE_NAME).then((cache) => {
					cache.put(e.request, response.clone());
					return response;
				});
			})
		);
		return;
	}
 
	e.respondWith(
		caches
			.match(e.request)
			.then((response) => {
				return (
					response ||
					fetch(e.request).then((response) => {
						return caches.open(CACHE_NAME).then((cache) => {
							cache.put(e.request, response.clone());
							return response;
						});
					})
				);
			})
			.catch(() => {
				return caches.match(OFFLINE_URL);
			})
	);
});

<link rel="manifest" href="https://xn--eckl3qmbc2cv902cnwa746d81h183l.com/manifest.json">
<meta name="theme-color" content="#f6cc82">
<meta name="apple-mobile-web-app-title" content="オンライン将棋教室 香">
<meta name="apple-mobile-web-app-capable" content="yes">
<meta name="apple-mobile-web-app-status-bar-style" content="default">
 
<script>
if ('serviceWorker' in navigator) {
	window.addEventListener('load', function () {
		navigator.serviceWorker.register('/sw.js').then(
			function (registration) {
				console.log('ServiceWorker registration successful with scope: ', registration.scope);
			},
			function (err) {
				console.log('ServiceWorker registration failed: ', err);
			}
		);
	});
}
</script>