Unit Test Controller Session Variables in MVC3 - unit-testing

I am unit testing my controller.
In one of my controller methods I am setting Session variables:
public void Index(){
Session["foo"] = "bar";
return View();
}
How can I unit test this? The problem is that the Session property is null when testing. Injecting is not possible because the Session property is readonly.
[TestMethod]
public void TestIndex()
// When
_controller.Index();
// Then
Assert.AreEqual("bar", _controller.Session["foo"])

Personally I like using the MvcContrib TestHelper which mocks all the HTTP pipeline:
[TestMethod]
public void HomeController_Index_Action_Should_Store_Bar_In_Session()
{
// arrange
var sut = new HomeController();
new TestControllerBuilder().InitializeController(sut);
// act
sut.Index();
// assert
Assert.AreEqual("bar", (string)sut.Session["foo"]);
}

This is what I used for Unit Test friendly Session Caching. By checking HttpContext.Current for null, you're by passing the caching for nunit tests and still allow your program to function normally.
This is the simplest solution without making a lot of code changes in your project.
internal class SessionCache
{
public static void Store(string key, object val) {
if (HttpContext.Current != null) {
HttpContext.Current.Session[key] = val;
}
}
public static object Retrieve(string key) {
if (HttpContext.Current != null) {
return HttpContext.Current.Session[key];
}
return null;
}
}

I always recommend wrapping the session object in another object. This not only gives you an easier way to test, but also makes all access to the session type safe. It is very easy to mistype a session key name in one spot in one place and then hunt for the bug for hours.
The object would have fields as
public Foo{
get{return Session["Foo"];}
set{Session["Foo"]=value;}
}
Once you are testing you can mock the session class with a dummy that only keeps state for the test.
The way I usually handle this is with dependency injection. How to set this up is a long examination. Here is a link to one way
http://weblogs.asp.net/shijuvarghese/archive/2011/01/21/dependency-injection-in-asp-net-mvc-3-using-dependencyresolver-and-controlleractivator.aspx

Related

How to unit test a service call in xUnit and nSubstitute

I been trying to figure out how i can unit test service and so far have got nowhere.
I am using xUnit and NSubstitute (as advised by friends), below is the simple test that i want to run (which fails currently).
public class UnitTest1
{
private readonly RallyService _rallyService;
public UnitTest1(RallyService rallyService)
{
_rallyService= rallyService;
}
[Fact]
public void Test1()
{
var result = _rallyService.GetAllRallies();
Assert.Equal(2, result.Count());
}
}
My rally service class makes a simple call to the db to get all Rally entites and returns those:
public class RallyService : IRallyService
{
private readonly RallyDbContext _context;
public RallyService(RallyDbContext context)
{
_context = context;
}
public IEnumerable<Rally> GetAllRallies()
{
return _context.Rallies;
}
}
Any guidance would be appreciated.
Since you use .NET Core, I assume you also use Entity Framework Core. While it was possible to mock most of the operations in the previous EF version, however the EF Core suggests to use in-memory database for unit testing. I.e. you don't need to mock RallyDbContext, hence NSubstitute is not needed for this particular test. You would need NSubstitute to mock the service when testing a controller or application using the service.
Below is your Test1 written using in-memory database.
public class UnitTest1
{
private readonly DbContextOptions<RallyDbContext> _options;
public UnitTest1()
{
// Use GUID for in-memory DB names to prevent any possible name conflicts
_options = new DbContextOptionsBuilder<RallyDbContext>()
.UseInMemoryDatabase(Guid.NewGuid().ToString())
.Options;
}
[Fact]
public async Task Test1()
{
using (var context = new RallyDbContext(_options))
{
//Given 2 records in database
await context.AddRangeAsync(new Rally { Name = "rally1" }, new Rally { Name = "rally2" });
await context.SaveChangesAsync();
}
using (var context = new RallyDbContext(_options))
{
//When retrieve all rally records from the database
var service = new RallyService(context);
var rallies = service.GetAllRallies();
//Then records count should be 2
Assert.Equal(2, rallies.Count());
}
}
}
A working test application with this unit test is in my GitHub for your reference. I used SQL Express in the actual app.
I don't think it is standard to have a unit test constructor with a parameter. The unit test runner will new up this class, and unless you are using something that will auto-inject that parameter I think the test will fail to run.
Here is a standard fixture layout:
public class SampleFixture {
[Fact]
public void SampleShouldWork() {
// Arrange stuff we need for the test. This may involved configuring
// some dependencies, and also creating the subject we are testing.
var realOrSubstitutedDependency = new FakeDependency();
realOrSubstitutedDependency.WorkingItemCount = 42;
var subject = new Subject(realOrSubstitutedDependency);
// Act: perform the operation we are testing
var result = subject.DoWork();
// Assert: check the subject's operation worked as expected
Assert.Equal(42, result);
}
[Fact]
public void AnotherTest() { /* ... */ }
}
If you need a common setup between tests, you can use a parameterless constructor and do common initialisation there.
In terms of the specific class you are trying to test, you need to make sure your RallyDbContext is in a known state to repeatably and reliably test. You may want to look up answers specific to testing Entity Framework for more information.

How to use Moq to Prove that the Method under test Calls another Method

I am working on a unit test of an instance method. The method happens to be an ASP.NET MVC 4 controller action, but I don't think that really matters much. We just found a bug in this method, and I'd like to use TDD to fix the bug and make sure it doesn't come back.
The method under test calls a service which returns an object. It then calls an internal method passing a string property of this object. The bug is that under some circumstances, the service returns null, causing the method under test to throw a NullReferenceException.
The controller uses dependency injection, so I have been able to mock the service client to have it return a null object. The problem is that I want to change the method under test so that when the service returns null, the internal method should be called with a default string value.
The only way I could think to do this is to use a mock for the class under test. I want to be able to assert, or Verify that this internal method has been called with the correct default value. When I try this, I get a MockException stating that the invocation was not performed on the mock. Yet I was able to debug the code and see the internal method being called, with the correct parameters.
What's the right way to prove that the method under test calls another method passing a particular parameter value?
I think there's a code smell here. The first question I'll ask myself in such a situation is, is the "internal" method really internal/ private to the controller under test. Is it the controller's responsibility to do the "internal" task? Should the controller change when the internal method's implementation changes? May be not.
In that case, I would pull out a new targeted class, which has a public method which does the stuff which was until now internal to the controller.
With this refactoring in place, I would use the callback mechanism of MOQ and assert the argument value.
So eventually, you will end up mocking two dependancies:
1. The external service
2. The new targeted class which has the controller's internal implementation
Now your controller is completely isolated and can be unit tested independently. Also, the "internal" implementation becomes unit testable and should have its own set of unit tests too.
So your code and test would look something like this:
public class ControllerUnderTest
{
private IExternalService Service { get; set; }
private NewFocusedClass NewFocusedClass { get; set; }
const string DefaultValue = "DefaultValue";
public ControllerUnderTest(IExternalService service, NewFocusedClass newFocusedClass)
{
Service = service;
NewFocusedClass = newFocusedClass;
}
public void MethodUnderTest()
{
var returnedValue = Service.ExternalMethod();
string valueToBePassed;
if (returnedValue == null)
{
valueToBePassed = DefaultValue;
}
else
{
valueToBePassed = returnedValue.StringProperty;
}
NewFocusedClass.FocusedBehvaior(valueToBePassed);
}
}
public interface IExternalService
{
ReturnClass ExternalMethod();
}
public class NewFocusedClass
{
public virtual void FocusedBehvaior(string param)
{
}
}
public class ReturnClass
{
public string StringProperty { get; set; }
}
[TestClass]
public class ControllerTests
{
[TestMethod]
public void TestMethod()
{
//Given
var mockService = new Mock<IExternalService>();
mockService.Setup(s => s.ExternalMethod()).Returns((ReturnClass)null);
var mockFocusedClass = new Mock<NewFocusedClass>();
var actualParam = string.Empty;
mockFocusedClass.Setup(x => x.FocusedBehvaior(It.IsAny<string>())).Callback<string>(param => actualParam = param);
//when
var controller = new ControllerUnderTest(mockService.Object, mockFocusedClass.Object);
controller.MethodUnderTest();
//then
Assert.AreEqual("DefaultValue", actualParam);
}
}
Edit: Based on the suggestion in the comments to use "verify" instead of callback.
Easier way to verify the parameter value is by using strict MOQ behavior and a verify call on the mock after system under test is executed.
Modified test could look like below:
[TestMethod]
public void TestMethod()
{
//Given
var mockService = new Mock<IExternalService>();
mockService.Setup(s => s.ExternalMethod()).Returns((ReturnClass)null);
var mockFocusedClass = new Mock<NewFocusedClass>(MockBehavior.Strict);
mockFocusedClass.Setup(x => x.FocusedBehvaior(It.Is<string>(s => s == "DefaultValue")));
//When
var controller = new ControllerUnderTest(mockService.Object, mockFocusedClass.Object);
controller.MethodUnderTest();
//Then
mockFocusedClass.Verify();
}
"The only way I could think to do this is to use a mock for the class under test."
I think you should not mock class under test. Mock only external dependencies your class under test has. What you could do is to create a testable-class. It would be a class which derives from your CUT and here you can catch the calls to the another method and verify it's parameter later. HTH
Testable class in the example is named MyTestableController
Another method is named InternalMethod.
Short example:
[TestClass]
public class Tests
{
[TestMethod]
public void MethodUnderTest_WhenServiceReturnsNull_CallsInternalMethodWithDefault()
{
// Arrange
Mock<IService> serviceStub = new Mock<IService>();
serviceStub.Setup(s => s.ServiceCall()).Returns((ReturnedFromService)null);
MyTestableController testedController = new MyTestableController(serviceStub.Object)
{
FakeInternalMethod = true
};
// Act
testedController.MethodUnderTest();
// Assert
Assert.AreEqual(testedController.SomeDefaultValue, testedController.FakeInternalMethodWasCalledWithThisParameter);
}
private class MyTestableController
: MyController
{
public bool FakeInternalMethod { get; set; }
public string FakeInternalMethodWasCalledWithThisParameter { get; set; }
public MyTestableController(IService service)
: base(service)
{ }
internal override void InternalMethod(string someProperty)
{
if (FakeInternalMethod)
FakeInternalMethodWasCalledWithThisParameter = someProperty;
else
base.InternalMethod(someProperty);
}
}
}
The CUT could look something like this:
public class MyController : Controller
{
private readonly IService _service;
public MyController(IService service)
{
_service = service;
}
public virtual string SomeDefaultValue { get { return "SomeDefaultValue"; }}
public EmptyResult MethodUnderTest()
{
// We just found a bug in this method ...
// The method under test calls a service which returns an object.
ReturnedFromService fromService = _service.ServiceCall();
// It then calls an internal method passing a string property of this object
string someStringProperty = fromService == null
? SomeDefaultValue
: fromService.SomeProperty;
InternalMethod(someStringProperty);
return new EmptyResult();
}
internal virtual void InternalMethod(string someProperty)
{
throw new NotImplementedException();
}
}

How to pass JSON to route from unit test?

I am unit testing my Laravel 4 Controller by mocking my repository that the controller expects. The problem is with the "store" function. This is the function that is called by Laravel when I do a POST to the given controller. The function gets called, but it is expected itemData as an input but I don't know how to provide that. Here is what I've tried:
ItemEntryController
class ItemEntryController extends BaseController
{
protected $itemRepo;
public function __construct(ItemEntryRepositoryInterface $itemRepo)
{
$this->itemRepo = $itemRepo;
}
public function store()
{
if(Input::has('itemData'))
{
$data = Input::get('itemData');
return $this->itemRepo->createAndSave($data);
}
}
}
Test class
<?php
use \Mockery as m;
class ItemEntryRouteAndControllerTest extends TestCase {
protected $testItemToStore = '{"test":12345}';
public function setUp()
{
parent::setUp();
$this->mock = $this->mock('Storage\ItemEntry\ItemEntryRepositoryInterface');
}
public function mock($class)
{
$mock = m::mock($class);
$this->app->instance($class, $mock);
return $mock;
}
public function testItemStore()
{
Input::replace($input = ['itemData' => $this->testItemToStore]);
$this->mock
->shouldReceive('createAndSave')
->once()
->with($input);
$this->call('POST', 'api/v1/tools/itementry/items');
}
Well, you got a few options.
Integration testing
You may want to follow the unit testing docs, which actually has a call() method which allows you set all of this. This bootstraps the app and will use your databases, etc.
This is more of an integration test than unit test, as it uses your actual class implementations.
This may actually be preferable, as Unit testing controllers may not actually make much sense (it doesn't do much, in theory, but call other already-unit-tested classes). But this gets into unit testing vs integration testing vs acceptance testing and all the nuances that apply therein. (Read up!)
Unit Testing
If you're actually looking to unit test, then you need to make your controller unit-testable (ha!). This (likely) means injecting all dependencies:
class ItemEntryController extends BaseController
{
protected $itemRepo;
// Not pictured here is actually making sure an instance of
// Request is passed to this controller (via Service Provider or
// IoC binding)
public function __construct(ItemEntryRepositoryInterface $itemRepo, Request $input)
{
$this->itemRepo = $itemRepo;
$this->request = $input;
}
public function store()
{
if($this->input->has('itemData'))
{
// Get() is actually a static method so we use
// the Request's way of getting the $_GET/$_POST variables
// see note below!
$data = $this->input->input('itemData');
return $this->itemRepo->createAndSave($data);
}
}
}
Sidenote: The Input facade is actually an instance of Request objet with an extra static method get()!
So now that we aren't using Input any longer, and are injecting the Request object, we can unit test this class by mocking the Request object.
Hope that helps!

Castle Windsor: unit test component lifecycle

I would like to write a non-regression test to validate that transient components are well released. Some are created by a direct injection in ctor, other by typed factories.
I thought that I could do this way:
// Given
var rootComponent = container.Resolve<IRootComponent>();
var c1 = rootComponent.C1;
var c2 = c1.C2;
etc.
Assert.True(Container.Kernel.ReleasePolicy.HasTrack(c1));
Assert.True(Container.Kernel.ReleasePolicy.HasTrack(c2));
// When
c1.Close();
// Then
Assert.False(Container.Kernel.ReleasePolicy.HasTrack(c1));
Assert.False(Container.Kernel.ReleasePolicy.HasTrack(c2));
HasTrack() always returns false, although if I look at the container in debug mode, I can see my components well tracked. Why is that? Do you have any suggestion for such a test?
Thx for your help
The reason that your components are not tracked is that the component and it's dependencies have no decomissioning requirements. In this case there is no reason for windsor to track them.
When using windsor in general you should only resolve on your container once to obtain your top level component. All other component are either injected or created by a factory. There is no need to worry about the live time of injected components. The container will handle it for you.
For transient components that you create with a factory you should be aware that they will never live (be tracked) longer then the factory it self. So if you don't mind that your components live at long as your factory there is no need to release them (using a destroy method on a factory).
For component that I want to make sure that I release them, I generally I create unit test for which I stub out the factory. That way it is easy to test that destroy is called.
I think with the approach that you are taking you are not just testing your code but also the container. IMHO windsor is already well tested, and test should focus on your own code.
Good luck,
Marwijn.
Two years too late, but here's a test.
public class DependsOnSomethingDisposable
{
private readonly SomethingDisposable _disposable;
public Boolean SomethingDisposableIsDisposed { get { return _disposable.Disposed; } }
public DependsOnSomethingDisposable(SomethingDisposable disposable)
{
_disposable = disposable;
}
}
public class SomethingDisposable : IDisposable
{
public Boolean Disposed { get; private set; }
public void Dispose()
{
Disposed = true;
}
}
[TestClass]
public class WindsorLifestyleTests
{
private IWindsorContainer _container;
[TestInitialize]
public void Setup()
{
_container = new WindsorContainer();
}
[TestCleanup]
public void Cleanup()
{
_container.Dispose();
}
[TestMethod]
public void TransientDependencyIsDisposed()
{
_container.Register(
Component.For<DependsOnSomethingDisposable>().LifestyleTransient(),
Component.For<SomethingDisposable>().LifestyleTransient()
);
var resolved = _container.Resolve<DependsOnSomethingDisposable>();
_container.Release(resolved);
Assert.IsTrue(resolved.SomethingDisposableIsDisposed);
}
[TestMethod]
public void NonTransientDependencyIsNotDisposed()
{
_container.Register(
Component.For<DependsOnSomethingDisposable>().LifestyleTransient(),
Component.For<SomethingDisposable>().LifestyleSingleton()
);
var resolved = _container.Resolve<DependsOnSomethingDisposable>();
_container.Release(resolved);
Assert.IsFalse(resolved.SomethingDisposableIsDisposed);
}
}

Create a Partial Stub in Microsoft Moles

I am pulling my hair out with this one. I have looked and cannot find a simple, clear example of creating and using a partial stub with Microsoft Moles. Maybe I'm missing somethimg, or have my code architected poorly, but I can't seem to get this to work.
Here's my class (simplified):
public class AccountService : IAccountService {
private readonly webServiceProxy IExternalWebServiceProxy;
public AccountService(IExternalWebServiceProxy webServiceProxy) {
this.webServiceProxy = webServiceProxy;
}
public List<AccountModel> GetAccounts(string customerId) {
var returnList = new List<AccountModel>();
var xmlResponse = webServiceProxy.GetAllCustomerAccounts(customerId);
var accountNodes = xmlResponse.SelectNodes("//AccountNodes");
if (accountNodes != null)
{
foreach (XmlNode node in accountNodes)
{
var account = this.MapAccountFromXml(node);
if (!string.IsNullOrEmpty(account.AccountNumber))
{
returnList.Add(account);
}
}
}
return returnList;
}
public AccountModel MapAccountFromXml(XmlNode node) {
if (!IsValidAccount(node) {
return null;
}
// This performs a lot of XML manipulation getting nodes based on attributes
// and mapping them to the various properties of the AccountModel. It's messy
// and I didn't want it inline with the other code.
return populatedAccountModel;
{
public bool IsValidAccount(XmlNode node)
{
var taxSelectValue = node.SelectSingleNode("//FORMAT/Field[#taxSelect='1']").First().Value;
var accountStatus = // similar to first line in that it gets a single node using a specific XPath
var maturityDate = // similar to first line in that it gets a single node using a specific XPath
var maturityValue = // similar to first line in that it gets a single node using a specific XPath
return taxSelectValue != string.Empty && taxSelectValue != "0" && (accountStatusValue != "CL" || (maturityDate.Year >= DateTime.Now.AddYears(-1).Year));
}
}
What I want to do is test my GetAccounts() method. I can stub out the IExternalWebServiceProxy call and return fake XML, but I have internal calls happening in my service since my GetAccounts() method calls MapAccountFromXml() which in turn calls IsValidAccount().
Perhaps the solution is to not worry about breaking out the long and involved MapAccountFromXml() and IsValidAccount() code and just put them inline into the GetAccount() call, but I would rather leave them broken out for code readability.
I have my Moles assembly created, and know I can create a stub version of my class like this
var stubWebService = SIExternalWebServiceProxy {
GetAllCustomerAccounts = delegate {
return SomeHelper.GetFakeXmlDocument();
}
}
var stubAccountService = new SAccountService() { callsBase = true; }
My problem is I don't know how to then override the internal calls to MapAccountFromXml and IsValidAccount and I don't want my Unit Test to be testing thos methods, I'd like to isolate GetAccounts for the test. I read somewhere the methods need to be virtual to be overriden in a partial stub, but could not find anything that then showed how to create a stub that overrides a few methods while calling the base for the one I want to test.
Peer put me on the right track, thank you.
It turned out that what I was looking for is called Detours in Moles. Rather than stub an interface using
var stubAccountService = new SIAccountService();
what I needed to do was create an instance of my AccountService and then detour all calls to the methods I wanted to mock, like this
var accountService = new AccountService();
MAccountService.AllInstances.MapAccountFromXmlXmlNode = delegate {
return new AccountModel();
};
The MAccountService is provided by Moles when you Mole your assembly. The only missing piece to this is that for this to work you need to add the following attribute to your test method:
[HostType("Moles")]
This worked for me locally, but in the end I had trouble getting TFS to do automated builds
UPDATE
I just stumbled on another way of doing this, while looking at Rhino Mocks. If the methods in the class being mocked are virtual then you can override them in the mock, like this:
var accountService = new SAccountService();
accountService.MapAccountFromXmlXmlNode = delegate
{
return new AccountModel();
}
Now I can call
accountService.GetMemberAccounts();
and when accountService makes its call to MapAccountFromXml it will be caught by the stub and processed as I deem necessary. No messing with HostType and it works like a charm.
To test methods in you class in issolation you do this with moles by making a mole for the IsValidAccount and MapAccountFromXml methods. Or make a stub implementation with stubs where you let the stub call the orriginal methode using base. Or what I think is a nicer solution, make a test class which overrides the methods you do want to stub (this is the same what a stub would do, except you see all what is happening in your own code):
public class TestHelperAccountService : AccountService {
public override AccountModel MapAccountFromXml(XmlNode node) {
return new AccountModel(){
//Accountmodelstub
};
{
public override bool IsValidAccount(XmlNode node)
{
return true;
}
}
This way you can do your test for the GetAccount method on your TestHelperAccountService class where you GetAccount method runs in full issolation. You can do the same for the methods like MapAccountFromXml to test them seperatly.