Unit testing with WebAPI odata - asp.net

Question

I am trying to move from a WebAPI based REST service, to one encompassing the new implimentation of OData. I have the service working correctly, but am at a loss on how create unit tests that will test the odata query options.
when unit testing WebAPI methods, I am used to building the httpRequestMessage and injecting it in the constructure:
var request = new HttpRequestMessage();
request.Headers.Add("UserName", "TestUser");
request.Headers.Add("Password", password);
request.Headers.Add("OverRideToken", "false");
request.Headers.Add("AccessSystem", "Mobile");
request.Headers.Add("Seed", "testSeed");
var token = new Token();
var authController = new AuthorizationController(request);
try
{
var returnValue = authController.Get();
how would I go about injecting the odata request? I need to verify that $filter, $inlinecount, and other options are returning the proper records.

Answer 1

You can either test your controller or you can test against a running instance of your Web API (you should probably do both).
Testing your controller won't achieve what you are trying to do, so you will want to test by creating a self hosted in-memory instance of your Web API application. You can then either use HttpClient in your test classes (you will have to manually construct OData requests), or you can use the WCF Data Services Client in your test classes (this will allow you to query via LINQ).
Here's an example using WCF Data Services Client:
public class ODataContainerFactory
{
static HttpSelfHostServer server;
public static MyApplicationServer.Acceptance.ODataService.Container Create(Uri baseAddress)
{
var config = new HttpSelfHostConfiguration(baseAddress);
// Remove self host requirement to run with Adminprivileges
config.HostNameComparisonMode = System.ServiceModel.HostNameComparisonMode.Exact;
// Register Web API and OData Configuration
WebApiConfig.Register(config);
// Configure IoC
ConfigureIoC(dataSource, config);
// Do whatever else, e.g. setup fake data sources etc.
...
// Start server
server = new HttpSelfHostServer(config);
server.OpenAsync().Wait();
// Create container
var container = new MyApplicationServer.Acceptance.ODataService.Container(new Uri(baseAddress.ToString() + "odata/"));
// Configure container
container.IgnoreResourceNotFoundException = true;
container.IgnoreMissingProperties = true;
return container;
}
private static void ConfigureIoC(MockDatasource dataSource, HttpSelfHostConfiguration config)
{
var container = new UnityContainer();
container.RegisterType<TypeA, TypeB>();
...
...
config.DependencyResolver = new IoCContainer(container);
}
public static void Destroy()
{
server.CloseAsync().Wait();
server.Dispose();
}
}
The key here is the WebApiConfig.Register(HttpConfiguration config) method call, which is calling your Web API project.
Note that prior to the above you will need:
Fire up your Web API project
In your test class add a Service Reference to your OData root path.
This will create a Container object (in the example above MyApplicationServer.Acceptance.ODataService.Container), which you can use to query your OData feed in your tests as follows:
var odataContainer = ODataContainerFactory.Create(new Uri("http://localhost:19194/");
var result = odataContainer.MyEntities
.Expand(s => s.ChildReferenceType)
.Where(s => s.EntityKey == someValue).SingleOrDefault();