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/call.ts

@@ -2,6 +2,15 @@ import limiter from './limiter';
 import { IUser } from '../../models/user';
 import { IApp } from '../../models/app';
 import endpoints from './endpoints';
+import { ApiError } from './error';
+import { apiLogger } from './logger';
+import { Response } from './define';
+
+const accessDenied = {
+	message: 'Access denied.',
+	code: 'ACCESS_DENIED',
+	id: '56f35758-7dd5-468b-8439-5d6fb8ec9b8e'
+};
 
 export default async (endpoint: string, user: IUser, app: IApp, data: any, file?: any) => {
 	const isSecure = user != null && app == null;
@@ -9,31 +18,43 @@ export default async (endpoint: string, user: IUser, app: IApp, data: any, file?
 	const ep = endpoints.find(e => e.name === endpoint);
 
 	if (ep == null) {
-		throw 'ENDPOINT_NOT_FOUND';
+		throw new ApiError({
+			message: 'No such endpoint.',
+			code: 'NO_SUCH_ENDPOINT',
+			id: 'f8080b67-5f9c-4eb7-8c18-7f1eeae8f709',
+		});
 	}
 
 	if (ep.meta.secure && !isSecure) {
-		throw 'ACCESS_DENIED';
+		throw new ApiError(accessDenied);
 	}
 
 	if (ep.meta.requireCredential && user == null) {
-		throw 'CREDENTIAL_REQUIRED';
+		throw new ApiError({
+			message: 'Credential required.',
+			code: 'CREDENTIAL_REQUIRED',
+			id: '1384574d-a912-4b81-8601-c7b1c4085df1',
+		});
 	}
 
 	if (ep.meta.requireCredential && user.isSuspended) {
-		throw 'YOUR_ACCOUNT_HAS_BEEN_SUSPENDED';
+		throw new ApiError(accessDenied, { reason: 'Your account has been suspended.' });
 	}
 
 	if (ep.meta.requireAdmin && !user.isAdmin) {
-		throw 'YOU_ARE_NOT_ADMIN';
+		throw new ApiError(accessDenied, { reason: 'You are not the admin.' });
 	}
 
 	if (ep.meta.requireModerator && !user.isAdmin && !user.isModerator) {
-		throw 'YOU_ARE_NOT_MODERATOR';
+		throw new ApiError(accessDenied, { reason: 'You are not a moderator.' });
 	}
 
 	if (app && ep.meta.kind && !app.permission.some(p => p === ep.meta.kind)) {
-		throw 'PERMISSION_DENIED';
+		throw new ApiError({
+			message: 'Your app does not have the necessary permissions to use this endpoint.',
+			code: 'PERMISSION_DENIED',
+			id: '1370e5b7-d4eb-4566-bb1d-7748ee6a1838',
+		});
 	}
 
 	if (ep.meta.requireCredential && ep.meta.limit) {
@@ -41,24 +62,31 @@ export default async (endpoint: string, user: IUser, app: IApp, data: any, file?
 			await limiter(ep, user); // Rate limit
 		} catch (e) {
 			// drop request if limit exceeded
-			throw 'RATE_LIMIT_EXCEEDED';
+			throw new ApiError({
+				message: 'Rate limit exceeded. Please try again later.',
+				code: 'RATE_LIMIT_EXCEEDED',
+				id: 'd5826d14-3982-4d2e-8011-b9e9f02499ef',
+			});
 		}
 	}
 
-	let res;
+	let res: Response;
 
 	// API invoking
 	try {
 		res = await ep.exec(data, user, app, file);
 	} catch (e) {
-		if (e && e.name == 'INVALID_PARAM') {
-			throw {
-				code: e.name,
-				param: e.param,
-				reason: e.message
-			};
-		} else {
+		if (e instanceof ApiError) {
 			throw e;
+		} else {
+			apiLogger.error(e);
+			throw new ApiError(null, {
+				e: {
+					message: e.message,
+					code: e.code,
+					stack: e.stack
+				}
+			});
 		}
 	}