core: add definePlugin syntax support

packages/center/index.ts

@@ -1,7 +1,7 @@
 import assert from 'assert';
 import crypto from 'crypto';
 import {
-    Context, db, ForbiddenError, Handler, post, Types, yaml,
+    db, definePlugin, ForbiddenError, Handler, post, Types, yaml,
 } from 'hydrooj';
 
 function decrypt(encrypted: string) {
@@ -67,6 +67,8 @@ class DataReportHandler extends Handler {
     }
 }
 
-export function apply(ctx: Context) {
-    ctx.Route('data_report', '/center/report', DataReportHandler);
-}
+export default definePlugin({
+    apply(ctx) {
+        ctx.Route('data_report', '/center/report', DataReportHandler);
+    },
+});

packages/hydrooj/src/plugin-api.ts

@@ -5,6 +5,7 @@ import _ from 'lodash';
 import moment from 'moment-timezone';
 import Schema from 'schemastery';
 import superagent from 'superagent';
+import { Context } from './context';
 import db from './service/db';
 export { ObjectID, ObjectId, FilterQuery } from 'mongodb';
 export * from './utils';
@@ -55,3 +56,9 @@ export { EventMap } from './service/bus';
 export {
     db, Schema, yaml, fs, AdmZip, superagent, _, moment,
 };
+export const definePlugin = <T = never>(args: {
+    using?: keyof Context[];
+    apply: (ctx: Context, config: T) => Promise<void> | void;
+    schema?: Schema<T>;
+    name?: string;
+}) => args;