strictNullChecks (#4666)

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src/services/push-notification.ts

@@ -1,26 +1,17 @@
 import * as push from 'web-push';
 import config from '../config';
 import { SwSubscriptions } from '../models';
-import { Meta } from '../models/entities/meta';
 import fetchMeta from '../misc/fetch-meta';
 
-let meta: Meta = null;
-
-setInterval(() => {
-	fetchMeta().then(m => {
-		meta = m;
-
-		if (meta.enableServiceWorker) {
-			// アプリケーションの連絡先と、サーバーサイドの鍵ペアの情報を登録
-			push.setVapidDetails(config.url,
-				meta.swPublicKey,
-				meta.swPrivateKey);
-		}
-	});
-}, 3000);
-
 export default async function(userId: string, type: string, body?: any) {
-	if (!meta.enableServiceWorker) return;
+	const meta = await fetchMeta();
+
+	if (!meta.enableServiceWorker || meta.swPublicKey == null || meta.swPrivateKey == null) return;
+
+	// アプリケーションの連絡先と、サーバーサイドの鍵ペアの情報を登録
+	push.setVapidDetails(config.url,
+		meta.swPublicKey,
+		meta.swPrivateKey);
 
 	// Fetch
 	const subscriptions = await SwSubscriptions.find({