Creating self-hosted WCF Data Services

This question came up the other night at the June NEBytes meeting after a presentation by Iain Angus (Black Marble) on WCF Data Services – can you host a WCF Data Service outside of IIS, inside a console application for example?

Since WCF Data Services are based upon the normal WCF architecture, you can self-host them just like any other WCF Service using a DataServiceHost. As a quick example, try this:

1. Create an entity

public class Person { public int ID { get; set; } public string Name { get; set; } }

2. Create a custom data context to return some data

public class ExampleDataContext {  
  public IQueryable People { 
    get { 
      return new List() { 
        new Person() { ID = 1, Name = "Steve"}, 
        new Person() { ID = 2, Name = "Dave"} 
      }.AsQueryable(); 
    } 
  } 
}

3. Create a class which inherits from DataService and specify your custom context. Also implement the static InitializeService() method and set up your access rules. This is the stuff that would normall be in your .svc code-behind in the IIS-hosted version:

public class PersonDataService : DataService {  
  public static void InitializeService(DataServiceConfiguration config) {
    config.SetEntitySetAccessRule("*", EntitySetRights.AllRead); 
  } 
}

4. Finally, in your startup code create an instance of a DataServiceHost, specifying the typeof DataService and the Uri to host on. Open the host and wait for a key-press to close it again:

DataServiceHost host = new DataServiceHost(typeof(PersonDataService),  
  new Uri [] { new Uri("http://localhost:999")});

try {  
  host.Open(); 
  Console.WriteLine("Host is running; press a key to stop"); 
  Console.ReadKey(); 
  host.Close(); 
} catch (Exception) { 
  host.Abort(); 
  throw; 
}

Using this example, you can now browse to http://localhost:999 in your browser and retrieve your data. You can also create a client proxy against this service at the same Uri just as normal.
You can read more information on hosting WCF Data Services in IIS or otherwise on MSDN.

View the example code on GitHub

Steve Hobbs