整理した

src/models/post-watching.ts

@@ -0,0 +1,12 @@
+import * as mongo from 'mongodb';
+import db from '../db/mongodb';
+
+const PostWatching = db.get<IPostWatching>('postWatching');
+export default PostWatching;
+
+export interface IPostWatching {
+	_id: mongo.ObjectID;
+	createdAt: Date;
+	userId: mongo.ObjectID;
+	postId: mongo.ObjectID;
+}