Introduce processor

src/server/api/common/watch-post.ts

@@ -0,0 +1,26 @@
+import * as mongodb from 'mongodb';
+import Watching from '../models/post-watching';
+
+export default async (me: mongodb.ObjectID, post: object) => {
+	// 自分の投稿はwatchできない
+	if (me.equals((post as any).user_id)) {
+		return;
+	}
+
+	// if watching now
+	const exist = await Watching.findOne({
+		post_id: (post as any)._id,
+		user_id: me,
+		deleted_at: { $exists: false }
+	});
+
+	if (exist !== null) {
+		return;
+	}
+
+	await Watching.insert({
+		created_at: new Date(),
+		post_id: (post as any)._id,
+		user_id: me
+	});
+};