title: How to deal with the timezone issue when storing dates in utc using mongod?
body: <p>I have a mongodb collection where each document has some attributes and a utc timestamp. I need to pull out data from the collection and use the aggregation framework because I use the data from the collection to display some charts on the user interface. However, I need to do the aggregation as per the user's timezone. Assuming I know the user's timezone(passed in the request from browser or in some other manner), is there any way to use the aggregation framework to aggregate based on the [client's] timezone?</p>