What are the steps to read an object from an ADO.net data service?

Question

Hi, I'm new to ADO.net data services (and to .net in general too..), I'm having this project where I need to setup a data service to read and write to a database with nHibernate, I've created the service:

[WebGet]
    [SingleResult]
    public Factory Factories(int Id)
    {
        try
        {
            Factory[] results = this.CurrentDataSource.Session.Linq<Factory>().Where(g => g.Id.Equals(Id)).ToArray();
            return results[0];
        }
        catch (Exception ex)
        {
            throw ex;
        }

And I've created a test for the service:

[Test]
        public void CanReadFactoryDataService()
        {
            DataServiceContext ctx = new
                  DataServiceContext(new Uri("http://localhost:1413/DataService.svc"));
            var Factories = ctx.Execute<Factory>(
                  new Uri("Factories?Id=54", UriKind.Relative));
            Assert.IsNotNull(Factories);
            Factory factory = Factories.First<Factory>();
            {
                Console.WriteLine(factory.NAME);
            }

When I run the service with the browser (eg: http://localhost:1413/DataService.svc/Factories?Id=54), the service returns:

<Factories p1:type="ADODS.Core.Factory">
<FactorY_CODE>abc</FactorY_CODE>
<NAME>Nameds</NAME>
<ADDRESS>Reinhardt strasse</ADDRESS>
<COMPENSATION_MODEL p1:null="true"/>
<B_CODE p1:null="true"/>
<Id p1:type="Edm.Int32">54</Id>
</Factories>

But when I run the unit test I'm getting this exception:

TestCase 'Tests.DataServicesTests.CanReadFactoryDataService'
failed: System.InvalidOperationException : La secuencia no contiene elementos (The sequence contains no elements)
    en System.Linq.Enumerable.First[TSource](IEnumerable`1 source)
    H:\ADODS\tests\ADODS.Tests\ADODS.Web\DataServicesTests.cs(22,0): en Tests.DataServicesTests.CanReadFactoryDataService()

I debugged the project, so the test connects to the service and the service returns the data, but

is there anything else I should do to convert the xml data into the actual object when I receive it?

I did a test, with a string object instead of a Factory and it worked, the problem seems to be with my classes. Am I missing something?

Answer 1

Finally I solved it: I Added a Service reference (Wich I hadn't done), and changed the test to:

[Test]
        public void CanReadFactoryDataService()
        {
            ServiceReference1.DataServiceContext ctx = new
                   ServiceReference1.DataServiceContext(new Uri("http://localhost:1413/DataService.svc"));
            var factories= ctx.Execute<Factory>(
                  new Uri("Factories?Id=54", UriKind.Relative));
            Assert.IsNotNull(factories);
            Factory factory = factories.First<Factory>();
            {
                Console.WriteLine(factory.ADDRESS);
            }

        }

And now it passes the test:

Reinhardt strasse

1 passed, 0 failed, 0 skipped, took 3.48 seconds (NUnit 2.5.2).

Now I think that was easy, but when you don't know, it's hard...