core: user: private and public projection (#507)

packages/hydrooj/src/lib/serializer.ts

@@ -0,0 +1,16 @@
+interface SerializeOptions {
+    showDisplayName: boolean;
+    currentSerializer?: (k: string, v: any) => any;
+}
+
+export default function serializer(options: SerializeOptions, ignoreSerializeFunction = false) {
+    options.currentSerializer = (k: string, v: any) => {
+        if (typeof k.startsWith !== 'function') console.log(k, v);
+        if (k.startsWith('_') && k !== '_id') return undefined;
+        if (typeof v === 'bigint') return `BigInt::${v.toString()}`;
+        if (!ignoreSerializeFunction && v && typeof v === 'object'
+            && 'serialize' in v && typeof v.serialize === 'function') return v.serialize(options);
+        return v;
+    };
+    return options.currentSerializer;
+}