Fun with NoRM 1

My previous posts on MongoDB have been pretty un-.NETty, in that I have focused almost entirely on how to work the DB through its JavaScript API. To remedy that, I shall write a few short posts on how to get rolling with MongoDB using NoRM, the coolest C# driver for MongoDB at the moment.

First post will be on how to connect and shove data into MongoDB.

Short introduction to NoRM

NoRM is “No Object-Relational Mapping”. It’s a .NET-driver, that allows you to map objects and their fields and aggregated objects into documents. I like NoRM because it’s successfully preserved that low-friction MongoDB-feeling, bridging C#’s capabilities nicely to those of JavaScript in the best possible way, providing some extra C#-goodies along the way. Please read on, you’ll see…

Connect to MongoDB

Easy – can be done like so:

using(var mongo = Mongo.Create("mongodb://hostname/dbname"))
{
   // go crazy in here!!1
}

Inserting a few documents

Inserting documents with NoRM is easy – just create a class with fields and aggregated objects, and make sure the class either has a property named something like “Id” or has a property decorated with [MongoIdentifier], e.g. like so:

public class Order
{
    public Order()
    {
        Id = ObjectId.NewObjectID();
        Items = new List<Item>();
    }
 
    public ObjectId Id { get; set; }
    public int Number { get; set; }
    public List<Item> Items { get; set; }
}
 
public class Item
{
    public string Name { get; set; }
    public int Amount { get; set; }
}

- and then go ahead and pull a strongly typed collection and insert documents into it:

var orders = mongo.GetCollection<Order>();
 
orders.Insert(new Order {
    Number = 1,
    Items = {
        new Item { Name = "beer" },
        new Item { Name = "nuts" },
    }
});

Now, to make this work I need to create five 200-line XML-files with mapping info etc. </kidding> no, seriously – that’s all it takes to persist an entire aggregate root!!

Pretty cool, eh? That’s what I meant when I said low friction. Stay tuned for more posts, e.g. on how to query a collection…