extend script of mongoshell

mongoshellextend.js

DBCollection.prototype.sample = function () {
  return this.find();
}

DBCollection.prototype.onedoc = function (userId) {
  return this.findOne({"_id": ObjectId(userId)});
}

DBCollection.prototype.pipeline = function (pipeline) {
  return this.find(pipeline);
}

DBCollection.prototype.findId = function (userId, pipeline) {
  return this.find({"_id": ObjectId(userId)}, pipeline);
}