title: Mongo BSON Types in Mongoose
body: <p>How can I use <code>Timestamp()</code> and other mongo shell operations mentioned  in <a href="https://docs.mongodb.org/manual/reference/bson-types/#timestamps" rel="nofollow noreferrer">mongodb docs</a> using mongoose?</p>
  
  <p>If I do something like <a href="https://stackoverflow.com/questions/25276725/mongodb-read-search-timestamp-based-on-oplog/25291671#25291671">this</a>, I get an error :</p>
  
  <pre><code>oplogModel.find({ts: {$gte: lastTimestamp, $lt: Timestamp(currTimestam
                                                      ^
  ReferenceError: Timestamp is not defined
  </code></pre>