Question

I would like to know the most efficient way to create /close MongoDb Connections.

I have a set of Restful services (created using c#), some of them get data form a MongoDb and some POST data in.

   public static MongoDatabase GetDatabase()
   {
      MongoServerSettings settings = new MongoServerSettings();
      settings.Server = new MongoServerAddress("localhost", 27017);
      MongoServer server = new MongoServer(settings);
      var database = server.GetDatabase("RapidDataStream");
      return database;
   }

I use the above connection form each of my services, for example a service to list all sensors.

public List<Sensor> getPublicSensors()
{
            List<Sensor> sensors = new List<Sensor>();
            MongoDatabase mySensor = GetDatabase();
            var query = Query.And(Query.EQ("User", BsonValue.Create("Public")));
            var mySensorRecords = mySensor.GetCollection("sensor_meta_data").Find(query);
            DataSet ds = new DataSet();

            foreach (var rec in mySensorRecords)
            {
                Sensor sensor = new Sensor();
                sensor.sensorId = rec["EnvId"].ToString();

                for (int i = 2; i < rec.ElementCount; i++)
                {
                    SensorObject so = new SensorObject();
                    so.fieldName = rec.GetElement(i).Name.ToString();
                    so.value = rec.GetElement(i).Value.ToString();
                    sensor.sensorObject.Add(so);
                }
                sensors.Add(sensor);
            }
            return sensors;
}

My question is that whether this is an efficient design or else how can I improve it?

Many Thanks.

Answer 1

I believe Mongo (or the driver) handles some things for us, so I use the Create method:

MongoServer.Create(....)

instead of creating a new instance. The Create method will create a new instance or return an existing instance (it is unique per server settings).

In fact, just to show you the actual method I use currently:

internal static MongoDatabase DB(IMongoConfig config)
{
    return MongoServer
           .Create(config.ConnectionString)    //This bit is getting the MongoServer
           .GetDatabase(config.DatabaseName);  //This bit gets the Database, which is returned
}

IMongoConfig is just a little DTO I use to specify, as you can see, the connection string and DB name I need – this combined with the workings of MongoServer.Create make it quite easy to handle connections to multiple databases from the same running code base.

public interface IMongoConfig
    {
        string ConnectionString { get; set; }
        string DatabaseName { get; set; }
    }