I'm a beginner at writing unit tests and I have a test I'm trying to get working. I'll start of by explaining what I'm trying to test.
I'm trying to test a method which saves messages in a Mvc 4 project. The method is called SaveMessage and is shown below.
namespace ChatProj.Service_Layer
{
public class UserService : IUserService
{
public MessageContext messageContext = new MessageContext();
public UserService()
{
_messageRepository = new MessageRepository(messageContext);
}
private IMessageRepository _messageRepository;
-> public void SaveMessage(Message message)
{
messageContext.Messages.Add(message);
_messageRepository.Save();
}
The _messageRepository.Save in the SaveMessage method is implemented in my DAL layer MessageRepository and looks like this:
public void Save()
{
context.SaveChanges();
}
This way of saving will seem a bit overcomplicated, but I structured the project this way because I didn't want the service layer (IUserService & UserService) to handle operations that could & should (i think) be handled by the Data Access Layer (IMessageRepository & MessageRepository).
Now comes the tricky part. I've been trying to understand how I could unit test this. This is my try:
namespace ChatProj.Tests
{
[TestFixture]
class MessageRepositoryTests
{
[SetUp]
public void Setup()
{
}
[Test]
public void SaveMessage_SaveWorking_VerifyUse()
{
//Arrange
var userServiceMock = new Mock<UserService>();
var message = new Message { MessageID = 0, Name = "Erland", MessageString = "Nunit Test", MessageDate = DateTime.Now };
var repositoryMock = new Mock<IMessageRepository>();
var contextMock = new Mock<MessageContext>();
MessageRepository messageRepository = new MessageRepository(contextMock.Object);
UserService userService = new UserService();
//Act
userService.SaveMessage(message);
//Assert
repositoryMock.Verify(m => m.Save());
userServiceMock.Verify(m => m.SaveMessage(message));
}
}
I get this error: Imgur link , and I'm not quite sure how to solve it. I've tried looking at several other SO posts but I fail to make the test work.
So I'm wondering, how do I practically get my Unit Test to work?
You should setup your MessageContext properties to return fake data and don't make real Db call with SaveChanges method.
Right now it still tries to access a real DB.
But you can setup only virtual properties or if it will be an inteface.
So the best solution is to extract an interface from your MessageContext and inject it into repository. Then you can easily mock your IMessageContext interface and force it to return appropriate in-memory data.
Take a look at these two lines:
UserService userService = new UserService();
//Act
userService.SaveMessage(message);
You're creating a userService instance, and then immediately saving your message. Now jump into the SaveMessage code.
public void SaveMessage(Message message)
{
messageContext.Messages.Add(message);
_messageRepository.Save();
}
Ok, now you're adding stuff to messageContext, and then calling _messageRepository.Save(). But where are messageContext and _messageRepository instantiated?
public MessageContext messageContext = new MessageContext();
public UserService()
{
_messageRepository = new MessageRepository(messageContext);
}
You're creating them at instantiation. The mocks that you've created in your test aren't being used. Instead of creating instances of these objects in the constructor, you might consider passing them into the UserService constructor as arguments. Then, you can pass in mocked instances in your test.
Related
I have an Azure Function as below. In the following code, I'm adding a product to the database using Repository & EF Core. Is there any way we can test it using Xunit? Currently, I'm testing this using Azure Service Bus Explorer.
[FunctionName("SaveProductData")]
public void Run([ServiceBusTrigger("mytopicname", Connection = "ServiceBusConnectionString")]
ProductItemUpdate message, ILogger log)
{
var product = new Domain.Entities.Product()
{
... prop init goes here.....
};
log.LogInformation($"Processed Product - Sain: {message.ProductId}");
_productRepository.Add(product);
}
To elaborate on scottdavidwalker's comment with a full example:
public class SaveProductDataTests
{
private readonly Mock<IProductRepository> _mockProductRepository = new Mock<IProductRepository>();
private readonly Mock<ILogger> _mockLogger = new Mock<ILogger>();
private readonly SaveProductData _saveProductData;
public SaveProductDataTests()
{
_saveProductData = new SaveProductData(_mockProductRepository.Object);
}
[Fact]
public void Given_When_Then()
{
// arrange
var productItemUpdate = new ProductItemUpdate();
// act
_saveProductData.Run(productItemUpdate, _mockLogger.Object);
// assert
_mockProductRepository.Verify(x => x.Add(It.Is<Product>(p => p.SomeProperty == "xyz")));
}
}
You need to create an instance of the class you are testing and mock the dependencies.
The Azure function is essentially a method (.Run()) inside the class which you can call on the instance.
In your unit test, you create the data to trigger the method and then make assertions on your mocks for what you expect to happen when the code runs for real.
I have the following (simplified) code.
public class Controller
{
private readonly IService _service;
public Controller(IService service)
{
_service = service;
}
public async Task<IHttpActionResult> Create(MyObject object)
{
var result = _service.method(object);
if (!result.Succeeded)
{
return this.GetErrorResult(object);
}
}
}
and SimpleInjector is used to inject the dependency between _service and its implementation class, like this:
public static void Register(Container container)
{
container.Register<IService, Service>();
}
As a note, injection and unit testing are new to me so I do not fully understand them, but am learning.
If I run the application through Swagger, all is working fine.
As a note, the Register function is called when I run the application through Swagger.
Now, I am trying to setup some unit tests using NUnit, and am Mocking the IService object like this:
var Service = new Mock<IService>();
Controller _controller = new Controller(Service.Object);
_controller.Create(new MyObject object());
which seems to be correct to me so far - although I am not sure?
The problem is that for the unit test, result is always null - I think the is because there is a problem with my Mock of the interface - it does not seem to be finding the method - it never steps into it and does not show up int he debugger.
As a note, for the unit test, the Register method does not get called. I did try calling it to register the dependency, but it does not help.
As I said above, this is all new to me and I am on the edge of my understanding on all of this.
I am out of ideas and do not know where to look from here, so any help would be greatly appreciated.
EDIT:
The original question had the following:
public async Task<IHttpActionResult> Create(string content)
which I have updated to:
public async Task<IHttpActionResult> Create(MyObject object)
Can anyone advise how I can pass in a generic reference to MyObject on the setup, without having to make an instance of this class.
So basically I want to tell it that an instance of this class will be passed in, without creating that instance.
I have tried the following:
Service.Setup(x => x.method(It.IsAny<MyObject>())
but it says cannot convert MethodGroup to MyObject
and here is the definition of IService:
public interface IService
{
IdentityResult method(ApplicationUser user, UserLoginInfo login);
}
You need to configure the Mock object to return something for IService.method as follows:
var Service = new Mock<IService>();
Service.Setup(x => x.method(It.IsAny<string>())
.Returns<string>(str => **whatever result you need**);
With the addition of your actual IService definition, you should change the Setup call to:
Service.Setup(x => x.method(It.IsAny<ApplicationUser>(), It.IsAny<UserLoginInfo>())
.Returns<ApplicationUser, UserLoginInfo>((user, login) => new IdentityResult(true));
The setup method has to be called on the Mock object.
var Service = new Mock<IService>();
Service.Setup(x=>x.method("argument")).Returns(YourReturnObject)
Controller _controller = new Controller(Service.Object);
Using your simplified example
public class Controller
{
private readonly IService _service;
public Controller(IService service)
{
_service = service;
}
public async Task<IHttpActionResult> Create(string content)
{
var result = await _service.method(content);
if (!result.Succeeded)
{
return this.GetErrorResult(result);
}
return Ok();
}
}
Lets assume IService is defined as
public interface IService {
Task<Result> method(string input);
}
public class Result {
public bool Succeeded { get; set; }
}
For the unit test you need to setup the mock to fake the actions wanted for the test
public async Task Controller_Given_Content_Should_Return_Ok() {
//Arrange
var input = "content";
var mockService = new Mock<IService>();
mockService
.Setup(m => m.method(input))
.ReturnAsync(new Result { Succeeded = true });
var _controller = new Controller(mockService.Object);
//Act
var result = await _controller.Create(input);
//Assert
Assert.IsNotNull(result);
Assert.IsInstanceOfType(result,typeof(OkResult));
}
Given that the method under test is asynchronous you would want to setup the test to be asynchronous as well.
My apologies in advanced for not knowing the technical name of this scenario. I am mocking for unit test and that is all fine. However on this section of code I have run into a scenario that exceeds my mocking knowledge. Basically I have MethodA that takes 3 parameters. One of the parameters is passed as another method's output.
When I step through the method passed as a parameter is executed
My difficulty is that the passed method is being executed BEFORE my mocked object. Now it seems like a simple solution...mock the second method as well...that is where my knowledge falls down. I don't know how to get the "second" method mock into the testing context.
My controller being tested (simplified of course):
public class OrderController : ApiController
{
public OrderController(IRepositoryK repositoryk)
{}
public HttpResponseMessage NewOrder()
{
...snip....
string x = repositoryk.MethodA("stuff", "moreStuff", MethodB("junk"));
}
public string MethodB(string data)
{
using (var client = new HttpClient())
{...make call to Google API...}
}
}
My test:
[TestMethod]
public void AddOrder_CorrectResponse()
{
private Mock<IRepositoryK> _repK = new Mock<IRepositoryK>();
_repK.Setup(x => x.MethodA(It.IsAny<string>(), It.IsAny<string>(), It.IsAny<string>()))
.Returns("Yippe");
//of course I've left out all the controller buildup and execution stuff.
}
So I really have no desire to dive into MethodB but it seems to be doing it anyway. What am I doing wrong?
TIA
Thank you for your responses. I understand completely what you are saying. I'm trying to get some testing coverage in place before refactoring. So is there no way of keeping methodB from executing and just let my repositoryK mock just return what I've specified in the setup.
Your code is not easy to test, because it has hard dependency on HttpClient. You have nicely separated repository implementation, but if you want to easily test the code you should also separate code which calls Google API. The idea is to have something like this:
// Add interfece for accessing Google API
public interface IGoogleClient
{
string GetData(string data);
}
// Then implementation is identical to MethodB implementation:
public class GoogleClient : IGoogleClient
{
public string GetData(string data)
{
using (var client = new HttpClient())
{
//...make call to Google API...
}
}
}
// Your controller should look like this:
public class OrderController : ApiController
{
private readonly IRepositoryK repositoryk;
private readonly IGoogleClient googleClient;
public OrderController(IRepositoryK repositoryk, IGoogleClient googleClient)
{
this.googleClient = googleClient;
this.repositoryk = repositoryk;
}
public HttpResponseMessage NewOrder()
{
//...snip....
string x = repositoryk.MethodA("stuff", "moreStuff", MethodB("junk"));
}
public string MethodB(string data)
{
return googleClient.GetData(data);
}
}
If you have such setup you can easily mock both IRepositoryK and IGoogleClient:
Mock<IRepositoryK> repK = new Mock<IRepositoryK>();
Mock<IGoogleClient> googleClient = new Mock<IGoogleClient>();
repK.Setup(x => x.MethodA(It.IsAny<string>(), It.IsAny<string>(), It.IsAny<string>())).Returns("Yippe");
googleClient.Setup(It.IsAny<string>()).Returns("something");
var controller = new OrderController(repK.Object, googleClient.Object);
// Test what you want on controller object
However, if you want to keep your code tightly coupled you can mock the call to MethodB with small changes.
First, you need to make method MethodB virtual, so it could be overridden in mock:
public virtual string MethodB(string data)
{
// your code
}
Then in your test instead of instantiating controller, instantiate and use mock of your controller:
var repK = new Mock<IRepositoryK>();
// create mock and pass the same constructor parameters as actual object
var controllerMock = new Mock<OrderController>(repK.Object);
controllerMock.CallBase = true;
// mock MethodB method:
controllerMock.Setup(x => x.MethodB(It.IsAny<string>())).Returns("data");
// call the method on mock object
// instead of calling MethodB you will get a mocked result
var result = controllerMock.Object.NewOrder();
I have a method CreateAccount to test. I am using Moq for the same.
Under CreateAccount method, there are multiple table insertion methods which belongs to two classes AccountRepository and BillingRepository
I have setup the Moq but don't know how to use multiple moq objects.
Below is some code snippet
Mock<AccountRepository> moq = new Mock<AccountRepository>();
Mock<BillingRepository> moqBill = new Mock<BillingRepository>();
moq.Setup(x => x.AddTable_1(new AddTable_1 { }));
moq.Setup(x => x.AddTable_2(new AddTable_2 { }));
moqBill.Setup(x => x.Table_3());
CreateAccount method takes four parameters and its under ApplicationService class
public class ApplicationService
{
public CreateAccountServiceResponse CreateAccount(AuthenticateApp App, CustomerInfo Customer, ServiceInfo Service, Optional op)
{
// SOME VALIDATION CODE
//.....................
// SOME CODE TO SAVE DATA INTO TABLES
obj_1.AddTable_1(objdata_1);
obj_1.AddTable_2(objdata_2);
obj_2.AddTable_3(objdata_3);
}
}
Please suggest some solution. How can these three methods will be skipped ?
Thanks in advance.
You have to provide some means to inject obj_1 and obj_2, since they seem to represent your instances of AccountRepository and BillingRepository, resp.
Typically, you might want to do this by using constructor injection. Extending the snippet you provided, this might look like this:
public class ApplicationService
{
private readonly AccountRepository _accountRepository;
private readonly BillingRepository _billingRepository;
public ApplicationService(AccountRepository accountRepository, BillingRepository billingRepository)
{
_accountRepository = accountRepository;
_billingRepository = billingRepository;
}
public CreateAccountServiceResponse CreateAccount(AuthenticateApp App, CustomerInfo Customer, ServiceInfo Service, Optional op)
{
// SOME VALIDATION CODE
//.....................
// SOME CODE TO SAVE DATA INTO TABLES
_accountRepository.AddTable_1(objdata_1);
_accountRepository.AddTable_2(objdata_2);
_billingRepository.AddTable_3(objdata_3);
}
}
Now you can inject your mocks into the class under test:
public void CreateAccount_WhenCalledLikeThis_DoesSomeCoolStuff()
{
var accountRepoMock = new Mock<AccountRepository>();
// set it up
var billingRepository = new Mock<BillingRepository>();
// set it up
var appService = new ApplicationService(accountRepoMock.Object, billingRepoMock.Objcet);
// More setup
// Act
var response = appService.CreateAccount(...);
// Assert on response and/or verify mocks
}
I always had a problem when unit testing classes that calls other classes, for example I have a class that creates a new user from a phone-number then saves it to the database and sends a SMS to the number provided.
Like the code provided below.
public class UserRegistrationProcess : IUserRegistration
{
private readonly IRepository _repository;
private readonly ISmsService _smsService;
public UserRegistrationProcess(IRepository repository, ISmsService smsService)
{
_repository = repository;
_smsService = smsService;
}
public void Register(string phone)
{
var user = new User(phone);
_repository.Save(user);
_smsService.Send(phone, "Welcome", "Message!");
}
}
It is a really simple class but how would you go about and test it?
At the moment im using Mocks but I dont really like it
[Test]
public void WhenRegistreringANewUser_TheNewUserIsSavedToTheDatabase()
{
var repository = new Mock<IRepository>();
var smsService = new Mock<ISmsService>();
var userRegistration = new UserRegistrationProcess(repository.Object, smsService.Object);
var phone = "07012345678";
userRegistration.Register(phone);
repository.Verify(x => x.Save(It.Is<User>(user => user.Phone == phone)), Times.Once());
}
[Test]
public void WhenRegistreringANewUser_ItWillSendANewSms()
{
var repository = new Mock<IRepository>();
var smsService = new Mock<ISmsService>();
var userRegistration = new UserRegistrationProcess(repository.Object, smsService.Object);
var phone = "07012345678";
userRegistration.Register(phone);
smsService.Verify(x => x.Send(phone, It.IsAny<string>(), It.IsAny<string>()), Times.Once());
}
It feels like I am testing the wrong thing here?
Any thoughts on how to make this better?
Refactoring the mocks out in the way that #Serghei suggests is good.
I also see that the name of the behaviour isn't actually describing the behaviour. I like to use the word "should", as in, "My class should do some stuff".
Your class shouldn't send the user to the database when it's registering a user. It should ask the repository to save the user. That's all. It doesn't know whether the repository sends it to the database, keeps it in memory or nukes it from orbit. It's not your class's responsibility.
By phrasing the behaviour this way, you can explicitly show - and help others understand - where the scope of your class's responsibility ends.
If you rename your method something like WhenRegisteringANewUser_AsksRepositoryToSaveIt() that might make the example you've given feel more natural.
In your case don't need to write
repository.Verify(x => x.Save(It.Is<User>(user => user.Phone == phone)), Times.Once());
because this method doesn't return a value
you can write
repository.VerifyAll();
Also for smsService it's a good way to use Moq.
look at after some refactor
Mock<IRepository<>> repository;
private Mock<ISmsService> smsService;
const string phone = "0768524440";
[SetUp]
public void SetUp()
{
repository = new Mock<IRepository<>>();
smsService = new Mock<ISmsService>();
}
[Test]
public void WhenRegistreringANewUser_TheNewUserIsSavedToTheDatabase()
{
var userRegistration = new UserRegistrationProcess(repository.Object, smsService.Object);
userRegistration.Register(phone);
repository.VerifyAll();
smsService.VerifyAll();
}