module.add(user,problem,record)

hydro/model/blacklist.js

@@ -0,0 +1,12 @@
+const
+    db = require('../service/db.js'),
+    coll = db.collection('blacklist');
+
+module.exports = {
+    add(ip) {
+        let expireAt = new Date(new Date().getTime() + 365 * 24 * 60 * 60 * 1000);
+        return coll.findOneAndUpdate({ _id: ip }, { $set: { expireAt } }, { upsert: true });
+    },
+    get: ip => coll.findOne({ _id: ip }),
+    delete: ip => coll.deleteOne({ _id: ip })
+};