},
}
+// TODO: adapt
+// Remove challenges older than 1 month, and 1to1 older than 36h
+//exports.removeOld = function()
+//{
+// var tsNow = new Date().getTime();
+// // 86400000 = 24 hours in milliseconds
+// var day = 86400000;
+// db.challenges.find({}, (err,challengeArray) => {
+// challengeArray.forEach( c => {
+// if (c._id.getTimestamp() + 30*day < tsNow //automatch
+// || (!!c.to && c._id.getTimestamp() + 1.5*day < tsNow)) //1 to 1
+// {
+// db.challenges.remove({"_id": c._id});
+// }
+// });
+// });
+//}
+
module.exports = ChallengeModel;