Hello Typescript!

hydro/model/system.ts

@@ -0,0 +1,45 @@
+import { FindOneAndUpdateOption } from 'mongodb';
+import * as db from '../service/db';
+
+const coll = db.collection('system');
+
+export async function get(_id: string) {
+    const doc = await coll.findOne({ _id });
+    if (doc) return doc.value;
+    return null;
+}
+
+export async function getMany(keys: string[]) {
+    const docs = await coll.find({ _id: { $in: keys } }).toArray();
+    const dict = {};
+    const res = [];
+    for (const doc of docs) {
+        dict[doc._id] = doc.value;
+    }
+    for (const key of keys) {
+        res.push(dict[key] || null);
+    }
+    return res;
+}
+
+export async function update(_id: string, operation: any, config: FindOneAndUpdateOption) {
+    await coll.findOneAndUpdate({ _id }, operation, config);
+    return get(_id);
+}
+
+export async function set(_id: string, value: any) {
+    await coll.findOneAndUpdate({ _id }, { $set: { value } }, { upsert: true });
+    return get(_id);
+}
+
+export function inc(field: string) {
+    return update(field, { $inc: { value: 1 } }, { upsert: true });
+}
+
+global.Hydro.model.system = {
+    get,
+    getMany,
+    update,
+    inc,
+    set,
+};