I am very new to unit testing when it comes to databases and especially entity framework and I am now stuck. I am using NUnit to test and mock the entities used and am working using a generic repository. My entity framework has a full set of POCO classes and the bit I am currently testing looks like this:
campaignRepoMock = new DynamicMock(typeof(IRepository<Campaign>));
campaignRepoMock.ExpectAndReturn("First", testCampaign, new Func<Campaign, bool>(c => c.CampaignID == testCampaign.CampaignID));
CampaignService campaignService = new CampaignService((IRepository<Campaign>)campaignRepoMock.MockInstance);
Campaign campaign = campaignService.GetCampaign(testCampaign.Key, ProjectId);
Assert.AreEqual(testCampaign, campaign);
testCampaign is a single POCO campaign test object. The method "First" in the IRepository looks like the following:
public T First(Func<T, bool> predicate)
{
return _objectSet.FirstOrDefault<T>(predicate);
}
The error I am getting from Nunit is
CampaignServiceTests.Campaign_Get_Campaign:
Expected: <System.Func`2[Campaign,System.Boolean]>
But was: <System.Func`2[Campaign,System.Boolean]>
So it is basically saying that it is getting what it is expecting, but its throwing an error? Maybe my understanding of this is all wrong, I just want to test the searching for a Campaign based on its key and the project it is linked to. The GetCampaigns method just search the repository sent to it for a campaign that has both of those items.
Can anyone point me to what I am doing wrong? Thanks in advance.
If I understand your code, over here
campaignRepoMock.ExpectAndReturn("First", testCampaign, new Func<Campaign, bool>(c => c.CampaignID == testCampaign.CampaignID));
you are setting up your mock object to return a function that is not identical to your testCampaign.
Assert.AreEqual() tests for strict equality. testCampaign and campaign are of the same type and have the same content, but refer to different objects.
What mocking framework are you using? Looks pretty complicated and confusing to me. For starting I would recommend something like Moq
Related
I am in the process of writing unit tests for a service class. This service class calls MyDomain.findAllByIdNotInList. The issue I am facing is that grails does not recognize NotInList as a dynamic finder for a mocked domain. I tried Metaclass-ing this functionality out, but was having issues with it.
Any creative ways for bypassing this short of turning the Unit Test into an Integration test? I would like to avoid this for multiple reasons (time to run, Only our Unit tests run at build time, etc)
Also, it is possible my metaclassing is written poorly:
MyDomain.metaClass.findAllByIdNotInList = {ArrayList list ->
return []
}
Edit: Using grails 1.3.7.
also tried
MyDomain.metaClass.findAllByIdNotInList = {deflist ->
return []
}
Bug report here:
http://jira.grails.org/browse/GRAILS-8593
#Sagar V's comment is correct you should be able to utilize all dynamic finders when a Domain is properly mocked. If you're using a version of Grails before 2.0 you'd have to extend GrailsUnitTestCase and call MockDomain(MyDomain) before attempting to invoke the dynamic finders. As an FYI your metaClassing is not written properly (in my opinion you should use the mocking framework to get your test working I'm providing the correct syntax so you can use it properly in the future).
MyDomain.metaClass.'static'.findAllByIdNotInList = {defList ->
[]
}
When the method that you're overriding is static you need to add the .'static'. inbetween the metaClass and the method name.
Short version of my questions:
Can anyone point me toward some good, detailed sources from which I
can learn how to implement testing in my MVC 3 application, using
NUnit, Ninject 2, and Moq?
Can anyone here help clarify for me how Controller-Repository
decoupling, mocking, and dependency injection work together?
Longer version of my questions:
What I'm trying to do ...
I am currently beginning to create an MVC 3 application, which will use Entity Framework 4, with a database first approach. I want to do this right, so I am trying to design the classes, layers, etc., to be highly testable. But, I have little to no experience with unit testing or integration testing, other than an academic understanding of them.
After lots of research, I've settle on using
NUnit as my testing framework
Ninject 2 as my dependency injection framework
Moq as my mocking framework.
I know the topic of which framework is best, etc., could enter into this, but at this point I really don't know enough about any of it to form a solid opinion. So, I just decided to go with these free solutions which seem to be well liked and well maintained.
What I've learned so far ...
I've spent some time working through some of this stuff, reading resources such as:
Implementing the Repository and Unit of Work Patterns in an
ASP.NET MVC Application
Building Testable ASP.NET MVC Applications
NerdDinner Step 12: Unit Testing
Using Repository and Unit of Work patterns with Entity Framework
4.0
From these resources, I've managed to workout the need for a Repository pattern, complete with repository interfaces, in order to decouple my controllers and my data access logic. I have written some of that into my application already, but I admit I am not clear as to the mechanics of the whole thing, and whether I am doing this decoupling in support of mocking, or dependency injection, or both. As such, I certainly wouldn't mind hearing from you guys about this too. Any clarity I can gain on this stuff will help me at this point.
Where things got muddy for me ...
I thought I was grasping this stuff pretty well until I started trying to wrap my head around Ninject, as described in Building Testable ASP.NET MVC Applications, cited above. Specifically, I got completely lost around the point in which the author begins describing the implementation of a Service layer, about half way into the document.
Anyway, I am now looking for more resources to study, in order to try to get various perspectives around this stuff until it begins to make sense to me.
Summarizing all of this, boiling it down to specific questions, I am wondering the following:
Can anyone point me toward some good, detailed sources from which I
can learn how to implement testing in my MVC 3 application, using
NUnit, Ninject 2, and Moq?
Can anyone here help clarify for me how Controller-Repository
decoupling, mocking, and dependency injection work together?
EDIT:
I just discovered the Ninject official wiki on Github, so I'm going to start working through that to see if it starts clarifying things for me. But, I'm still very interested in the SO community thoughts on all of this :)
If you are using the Ninject.MVC3 nuget package, then some of the article you linked that was causing confusion will not be required. That package has everything you need to start injecting your controllers which is probably the biggest pain point.
Upon installing that package, it will create a NinjectMVC3.cs file in the App_Start folder, inside that class is a RegisterServices method. This is where you should create the bindings between your interfaces and your implementations
private static void RegisterServices(IKernel kernel)
{
kernel.Bind<IRepository>().To<MyRepositoryImpl>();
kernel.Bind<IWebData>().To<MyWebDAtaImpl>();
}
Now in your controller you can use constructor injection.
public class HomeController : Controller {
private readonly IRepository _Repo;
private readonly IWebData _WebData;
public HomeController(IRepository repo, IWebData webData) {
_Repo = repo;
_WebData = webData;
}
}
If you are after very high test coverage, then basically anytime one logical piece of code (say controller) needs to talk to another (say database) you should create an interface and implementation, add the definition binding to RegisterService and add a new constructor argument.
This applies not only to Controller, but any class, so in the example above if your repository implementation needed an instance of WebData for something, you would add the readonly field and the constructor to your repository implementation.
Then when it comes to testing, what you want to do is provide mocked version of all required interfaces, so that the only thing you are testing is the code in the method you are writing the test for. So in my example, say that IRepository has a
bool TryCreateUser(string username);
Which is called by a controller method
public ActionResult CreateUser(string username) {
if (_Repo.TryCreateUser(username))
return RedirectToAction("CreatedUser");
else
return RedirectToAction("Error");
}
What you are really trying to test here is that if statement and the return types, you do not want to have to create a real repository that will return true or false based on special values you give it. This is where you want to mock.
public void TestCreateUserSucceeds() {
var repo = new Mock<IRepository>();
repo.Setup(d=> d.TryCreateUser(It.IsAny<string>())).Returns(true);
var controller = new HomeController(repo);
var result = controller.CreateUser("test");
Assert.IsNotNull(result);
Assert.IsOfType<RedirectToActionResult>(result)
Assert.AreEqual("CreatedUser", ((RedirectToActionResult)result).RouteData["Action"]);
}
^ That won't compile for you as I know xUnit better, and do not remember the property names on RedirectToActionResult from the top of my head.
So to sum up, if you want one piece of code to talk to another, whack an interface in between. This then allows you to mock the second piece of code so that when you test the first you can control the output and be sure you are testing only the code in question.
I think it was this point that really made the penny drop for me with all this, you do this not necessarily becase the code demands it, but because the testing demands it.
One last piece of advice specific to MVC, any time you need to access the basic web objects, HttpContext, HttpRequest etc, wrap all these behind an interface as well (like the IWebData in my example) because while you can mock these using the *Base classes, it becomes painful very quickly as they have a lot of internal dependencies you also need to mock.
Also with Moq, set the MockBehaviour to Strict when creating mocks and it will tell you if anything is being called that you have not provided a mock for.
Here is the application that I'm creating. It is open source and available on github, and utilizes all of the required stuff - MVC3, NUnit, Moq, Ninject - https://github.com/alexanderbeletsky/trackyt.net/tree/master/src
Contoller-Repository decoupling is simple. All data operations are moved toward the Repository. Repository is an implementation of some IRepository type. The controller never creates repositories inside itself (with the new operator) but rather receives them either by constructor argument or property.
.
public class HomeController {
public HomeController (IUserRepository users) {
}
}
This technique is called "Inversion of Control." To support inversion of control you have to provide some "Dependency Injection" framework. Ninject is a good one. Inside Ninject you associate some particular interface with an implementation class:
Bind<IUserRepository>().To<UserRepository>();
You also substitute the default controller factory with your custom one. Inside the custom one you delegate the call to the Ninject kernel:
public class TrackyControllerFactory : DefaultControllerFactory
{
private IKernel _kernel = new StandardKernel(new TrackyServices());
protected override IController GetControllerInstance(
System.Web.Routing.RequestContext requestContext,
Type controllerType)
{
if (controllerType == null)
{
return null;
}
return _kernel.Get(controllerType) as IController;
}
}
When the MVC infrastructure is about to create a new controller, the call is delegated to the custom controller factory GetControllerInstance method, which delegates it to Ninject. Ninject sees that to create that controller the constructor has one argument of type IUserRepository. By using the declared binding, it sees that "I need to create a UserRepository to satisfy the IUserRepository need." It creates the instance and passes it to the constructor.
The constructor is never aware of what exact instance would be passed inside. It all depends on the binding you provide for that.
Code examples:
https://github.com/alexanderbeletsky/trackyt.net/blob/master/src/Web/Infrastructure/TrackyServices.cs https://github.com/alexanderbeletsky/trackyt.net/blob/master/src/Web/Infrastructure/TrackyControllerFactory.cs https://github.com/alexanderbeletsky/trackyt.net/blob/master/src/Web/Controllers/LoginController.cs
Check it out : DDD Melbourne video - New development workflow
The whole ASP.NET MVC 3 development process was very well presented.
The third party tools I like most are:
Using NuGet to install Ninject to enable DI throughout the MVC3
framework
Using NuGet to install nSubstite to create mocks to enable unit
testing
This is a tough one because not too many people use Pex & Moles or so I think (even though Pex is a really great product - much better than any other unit testing tool)
I have a Data project that has a very simple model with just one entity (DBItem). I've also written a DBRepository within this project, that manipulates this EF model. Repository has a method called GetItems() that returns a list of business layer items (BLItem) and looks similar to this (simplified example):
public IList<BLItem> GetItems()
{
using (var ctx = new EFContext("name=MyWebConfigConnectionName"))
{
DateTime limit = DateTime.Today.AddDays(-10);
IList<DBItem> result = ctx.Items.Where(i => i.Changed > limit).ToList();
return result.ConvertAll(i => i.ToBusinessObject());
}
}
So now I'd like to create some unit tests for this particular method. I'm using Pex & Moles. I created my moles and stubs for my EF object context.
I would like to write parametrised unit test (I know I've first written my production code, but I had to, since I'm testing Pex & Moles) that tests that this method returns valid list of items.
This is my test class:
[PexClass]
public class RepoTest
{
[PexMethod]
public void GetItemsTest(ObjectSet<DBItem> items)
{
MEFContext.ConstructorString = (#this, name) => {
var mole = new SEFContext();
};
DBRepository repo = new DBRepository();
IList<BLItem> result = repo.GetItems();
IList<DBItem> manual = items.Where(i => i.Changed > DateTime.Today.AddDays(-10));
if (result.Count != manual.Count)
{
throw new Exception();
}
}
}
Then I run Pex Explorations for this particular parametrised unit test, but I get an error path bounds exceeded. Pex starts this test by providing null to this test method (so items = null). This is the code, that Pex is running:
[Test]
[PexGeneratedBy(typeof(RepoTest))]
[Ignore("the test state was: path bounds exceeded")]
public void DBRepository_GetTasks22301()
{
this.GetItemsTest((ObjectSet<DBItem>)null);
}
This was additional comment provided by Pex:
The test case ran too long for these inputs, and Pex stopped the analysis. Please notice: The method Oblivious.Data.Test.Repositories.TaskRepositoryTest.b__0 was called 50 times; please check that the code is not stuck in an infinite loop or recursion. Otherwise, click on 'Set MaxStack=200', and run Pex again.
Update attribute [PexMethod(MaxStack = 200)]
Question
Am I doing this the correct way or not? Should I use EFContext stub instead? Do I have to add additional attributes to test method so Moles host will be running (I'm not sure it does now). I'm running just Pex & Moles. No VS test or nUnit or anything else.
I guess I should probably set some limit to Pex how many items should it provide for this particular test method.
Moles is not designed to test the parts of your application that have external dependencies (e.g. file access, network access, database access, etc). Instead, Moles allows you to mock these parts of your app so that way you can do true unit testing on the parts that don't have external dependencies.
So I think you should just mock your EF objects and queries, e.g., by creating in-memory lists and having query methods return fake data from those lists based on whatever criteria is relevant.
I am just getting to grips with pex also ... my issues surrounded me wanting to use it with moq ;)
anyway ...
I have some methods similar to your that have the same problem. When i increased the max they went away. Presumably pex was satisfied that it had sufficiently explored the branches. I have methods where i have had to increase the timeout on the code contract validation also.
One thing that you should probably be doign though is passing in all the dependant objects as parameters ... ie dont instantiate the repo in the method but pass it in.
A general problem you have is that you are instantiating big objects in your method. I do the same in my DAL classes, but then i am not tryign to unit test them in isolation. I build up datasets and use this to test my data access code against.
I use pex on my business logic and objects.
If i were to try and test my DAL code id have to use IOC to pass the datacontext into the methods - which would then make testing possible as you can mock the data context.
You should use Entity Framework Repository Pattern: http://www.codeproject.com/KB/database/ImplRepositoryPatternEF.aspx
I'm working on a web application that is built over Sitecore CMS. I was wondering if we could unit test for example a method that takes some data from Sitecore makes some processing with it and spits out a result. I would like to test all the logic within the method via a unit test.
I pretty confused after searching the internet wide and deep. Some say that this kind of testing is actually integration testing and not unit testing and I should test only the code that has no Sitecore calls, others say that this is not possible because the Sitecore context would be missing.
I would like to ask for your help experienced fellow programmers:
Can I unit test a method that contains Sitecore calls ? If YES, how ? If NO, why ? Is there any workaround ?
The project is at its beginning, so there will be no problem in choosing between unit testing frameworks such as MSTest or Nunit, if it is the case that the solution is related to the unit testing framework of choice.
It's pretty hard to find out anything about Sitecore without providing email and living through the sales pitch, so I'll just provide a generic approach on how to do something like this.
First and foremost, you assume that the Sitecore API is guaranteed to work - i.e. it's a framework - and you don't unit test it. You should be unit testing your interactions with it.
Then, download MOQ and read the quick start on how to use it. This is my preferred mocking framework. Feel free to use other frameworks if you wish.
Hopefully, Sitecore API provides a way for you to create data objects without dealing with persistence - i.e. to simply create a new instance of whatever it is you are interested in. Here is my imaginary API:
public class Post {
public string Body {get;set;}
public DateTime LastModified {get;set;}
public string Title {get;set;}
}
public interface ISiteCorePosts {
public IEnumerable<Post> GetPostsByUser(int userId);
}
In this case unit testing should be fairly easy. With a bit of Dependency Injection, you can inject the SiteCore interfaces into your component and then unit test it.
public class MyPostProcessor {
private readonly ISiteCorePosts m_postRepository;
public MyPostProcessor(ISiteCorePosts postRepository) {
m_postRepository = postRepository;
}
public void ProcessPosts(int userId) {
var posts = m_postRepository.GetPostsByUser(userId);
//do something with posts
}
}
public class MyPostProcessorTest {
[TestMethod]
ProcessPostsShouldCallGetPostsByUser() {
var siteCorePostsMock = new Mock<ISiteCorePosts>();
//Sets up the mock to return a list of posts when called with userId = 5
siteCorePostsMock.Setup(m=>m.GetPostsByUser(5)).Returns(new List<Post>{/*fake posts*/});
MyPostProcessor target = new MyPostProcessor(siteCorePostsMock.Object);
target.ProcessPosts(5);
//Verifies that all setups are called
siteCorePostsMock.VerifyAll();
}
}
If ISiteCorePosts is not, in fact, an interface and is a concrete class whose methods are not virtual and thus cannot be mocked, you will need to use Facade pattern to wrap the SiteCore interaction to make it more testing friendly.
public class SiteCorePostsFacade {
SiteCorePosts m_Posts = new SiteCorePosts();
//important - make this method virtual so it can be mocked without needing an interface
public virtual IEnumerable<Post> GetPostsByUser(int userId) {
return m_Posts.GetPostsByUser(userId);
}
}
You then proceed to use SiteCorePostsFacade as though it was an interface in the previous example. Good thing about MOQ is that it allows you to mock concrete classes with virtual methods, not just interfaces.
With this approach, you should be able to inject all sorts of data into your application to test all interactions with SiteCore API.
we have used a custom WebControl placed on a WebForm for our integration tests some years now, which wraps the NUnit Test Suite runner functionality much like the NUnit GUI. It show a pretty grid of executed tests with links to fixtures and categories to execute specific tests. Its created much like described here http://adeneys.wordpress.com/2010/04/13/new-technique-for-unit-testing-renderings-in-sitecore/ (the custom test runner part). Our implementation can also return raw NUnit xml for further processing by for example a build server.
I've tried MSTest a while back and it also works when specified that it should launch a WebDev / IIS site to test. It works but is extremely slow compared to above solution.
Happy testing!
Short answer:
You need to mock calls to SiteCore CMS.
Long answer:
I am not aware about SiteCore CMS. But, from your question looks like it is something that is external to your application. Components external to your system should always be used via interface. This has two benefits:
If you want to use another CMS system, you can easily do as your application is just talking to an interface.
It helps you with behavior testing by mocking the interface.
The code you write is your responsibility and hence you should only unit test that piece of code. Your unit tests should ensure that your code calls appropriate SiteCode CMS methods in various scenarios (behavior tests). You can do this using mocking. I use moq for mocking.
As tugga said, it depends upon how tightly the code you want to test is coupled to SiteCore. If it's something like:
SomeSiteCoreService siteCoreDependency = new SomeSiteCoreService()
Then this would be very difficult to test. If SiteCore provides you an interface, then you have more flexibility to unit test it. You could pass the implementation into your method either (contstructor, class property, or method parameter) and then you can send in a fake implementation of that service.
If they do not provide you with an interface, then you have to do a little more work. You would write an adapter interface of your own and the default implementation would delegate to the 3rd party dependency.
public interface ICMSAdapter{
void DoSomethingWithCMS()
}
public class SiteCoreCMSAdapter: ICMSAdapter{
SiteCoreService _cms = new SiteCoreService();
public void DoSomethingWithCMS(){
_cms.DoSomething();
}
That keeps your 3rd party dependencies at arms length and provides seams to all sorts of cool things, like unit tests and you do interception style architecture and do your own thing before and after the call.
}
I was able to get unit tests to interact with sitecore api in VS 2015. The same test throws a StackOverflow exception when run in VS 2012.
For example, this method call runs fine in VS2015 but not VS2015:
Context.SetActiveSite("mysite");
quick note: this assumes you have a site named mysite setup in your config file
A few weeks ago I jumped on the MEF (ComponentModel) bandwagon, and am now using it for a lot of my plugins and also shared libraries. Overall, it's been great aside from the frequent mistakes on my part, which result in frustrating debugging sessions.
Anyhow, my app has been running great, but my MEF-related code changes have caused my automated builds to fail. Most of my unit tests were failing simply because the modules I was testing were dependent upon other modules that needed to be loaded by MEF. I worked around these situations by bypassing MEF and directly instantiating those objects.
In other words, via MEF I would have something like
[Import]
public ICandyInterface ci { get; set; }
and
[Export(typeof(ICandyInterface))]
public class MyCandy : ICandyInterface
{
[ImportingConstructor]
public MyCandy( [Import("name_param")] string name) {}
...
}
But in my unit tests, I would just use
CandyInterface MyCandy = new CandyInterface( "Godiva");
In addition, the CandyInterface requires a connection to a database, which I have worked around by just adding a test database to my unit test folder, and I have NUnit use that for all of the tests.
Ok, so here are my questions regarding this situation:
Is this a Bad Way to do things?
Would you recommend composing parts in [SetUp]
I haven't yet learned how to use mocks in unit testing -- is this a good example of a case where I might want to mock the underlying database connection (somehow) to just return dummy data and not really require a database?
If you've encountered something like this before, can you offer your experience and the way you solved your problem? (or should this go into the community wiki?)
It sounds like you are on the right track. A unit test should test a unit, and that's what you do when you directly create instances. If you let MEF compose instances for you, they would tend towards integration tests. Not that there's anything wrong with integration tests, but unit tests tend to be more maintainable because you test each unit in isolation.
You don't need a container to wire up instances in unit tests.
I generally recommend against composing Fixtures in SetUp, as it leads to the General Fixture anti-pattern.
It is best practice to replace dependencies with Test Doubles. Dynamic mocks is one of the more versatile ways of doing this, so definitely something you should learn.
I agree that creating the DOCs manually is much better than using MEF composition container to satisfy imports, but regarding the note 'compositing fixtures in setup leads to the general fixture anti pattern' - I want to mention that that's not always the case.
If you’re using the static container and satisfy imports via CompositionInitializer.SatisfyImports you will have to face the general fixture anti pattern as CompositionInitializer.Initialize cannot be called more than once. However, you can always create CompositionContainer, add catalogs, and call SatisyImportOnce on the container itself. In that case you can use a new CompositionContainer in every test and get away with facing the shared/general fixture anti pattern
I blogged on how to do unit tests (not nunit but works just the same) with MEF.
The trick was to use a MockExportProvider and i created a test base for all my tests to inherit from.
This is my main AutoWire function that works for integration and unit tests:
protected void AutoWire(MockExportProvider mocksProvider, params Assembly[] assemblies){
CompositionContainer container = null;
var assCatalogs = new List<AssemblyCatalog>();
foreach(var a in assemblies)
{
assCatalogs.Add(new AssemblyCatalog(a));
}
if (mocksProvider != null)
{
var providers = new List<ExportProvider>();
providers.Add(mocksProvider); //need to use the mocks provider before the assembly ones
foreach (var ac in assCatalogs)
{
var assemblyProvider = new CatalogExportProvider(ac);
providers.Add(assemblyProvider);
}
container = new CompositionContainer(providers.ToArray());
foreach (var p in providers) //must set the source provider for CatalogExportProvider back to the container (kinda stupid but apparently no way around this)
{
if (p is CatalogExportProvider)
{
((CatalogExportProvider)p).SourceProvider = container;
}
}
}
else
{
container = new CompositionContainer(new AggregateCatalog(assCatalogs));
}
container.ComposeParts(this);
}
More info on my post: https://yoavniran.wordpress.com/2012/10/18/unit-testing-wcf-and-mef/