Improve error handling of API (#4345)

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* Update attached_notes.ts

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* Refactor

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* Update call.ts

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* ✌️

* Fix

src/server/api/endpoints/sw/register.ts

@@ -21,7 +21,7 @@ export const meta = {
 	}
 };
 
-export default define(meta, (ps, user) => new Promise(async (res, rej) => {
+export default define(meta, async (ps, user) => {
 	// if already subscribed
 	const exist = await Subscription.findOne({
 		userId: user._id,
@@ -34,10 +34,10 @@ export default define(meta, (ps, user) => new Promise(async (res, rej) => {
 	const instance = await fetchMeta();
 
 	if (exist != null) {
-		return res({
+		return {
 			state: 'already-subscribed',
 			key: instance.swPublicKey
-		});
+		};
 	}
 
 	await Subscription.insert({
@@ -47,8 +47,8 @@ export default define(meta, (ps, user) => new Promise(async (res, rej) => {
 		publickey: ps.publickey
 	});
 
-	res({
+	return {
 		state: 'subscribed',
 		key: instance.swPublicKey
-	});
-}));
+	};
+});