With the interface below:
public interface IRepository<T>
{
T FirstOrDefault(Func<T, bool> predicate);
}
Implemented like so:
private IRepository<Foo> Repository {get;set;}
public FooService(IRepository<Foo> repository)
{
Repository = repository;
}
public void Foo(int bar)
{
var result = Repository.FirstOrDefault(x => x.Id.Equals(bar));
if (result == null)
{
throw new Exception("Returned null, not what I expected!");
}
}
If I write a test like this:
repos = MockRepository.GenerateMock<IRepository<Foo>>(null);
repos.Expect(x => x.FirstOrDefault(y => y.Id.Equals(Arg<int>.Is.Anything))).Throw(new Exception("This exception should be thrown!"));
FooService f = new FooService(repos);
f.Foo(1);
//expecting exception to be thrown
I do not get the expected exception thrown, so I am presuming that mocked call is being ignored/not called.
However if I add IgnoreArguments() it is called and I do get the expected exception.
repos.Expect(x => x.FirstOrDefault(y => y.Id.Equals(Arg<int>.Is.Anything))).IgnoreArguments().Throw(new Exception("This exception should be thrown!"));
Any thoughts as to what it is I am doing wrong?
Related
I have a .Net Core 3 application and am trying to test calls to ILogger in my method:
public class MyClass
{
private readonly ILogger<MyClass> _logger;
public MyClass(ILogger<MyClass> logger)
{
_logger = logger;
}
public void MyMethod(string message)
{
_logger.LogError(message);
}
}
Having found answers here on SO and on blogs, I know that I have to test against the interface method, not the extension method, so I have this test:
[TestMethod]
public void MyMethodTest()
{
// Arrange
var logger = Substitute.For<ILogger<MyClass>>();
var myClass = new MyClass(logger);
var message = "a message";
// Act
myClass.MyMethod(message);
// Assert
logger.Received(1).Log(
LogLevel.Error,
Arg.Any<EventId>(),
Arg.Is<object>(o => o.ToString() == message),
null,
Arg.Any<Func<object, Exception, string>>());
}
However, this isn't working and I get this error:
Test method MyLibrary.Tests.MyClassTests.MyMethodTest threw exception:
NSubstitute.Exceptions.ReceivedCallsException: Expected to receive exactly 1 call matching:
Log<Object>(Error, any EventId, o => (o.ToString() == value(MyLibrary.Tests.MyClassTests+<>c__DisplayClass0_0).message), <null>, any Func<Object, Exception, String>)
Actually received no matching calls.
at NSubstitute.Core.ReceivedCallsExceptionThrower.Throw(ICallSpecification callSpecification, IEnumerable`1 matchingCalls, IEnumerable`1 nonMatchingCalls, Quantity requiredQuantity)
at NSubstitute.Routing.Handlers.CheckReceivedCallsHandler.Handle(ICall call)
at NSubstitute.Routing.Route.Handle(ICall call)
at NSubstitute.Core.CallRouter.Route(ICall call)
at NSubstitute.Proxies.CastleDynamicProxy.CastleForwardingInterceptor.Intercept(IInvocation invocation)
at Castle.DynamicProxy.AbstractInvocation.Proceed()
at NSubstitute.Proxies.CastleDynamicProxy.ProxyIdInterceptor.Intercept(IInvocation invocation)
at Castle.DynamicProxy.AbstractInvocation.Proceed()
at Castle.Proxies.ObjectProxy.Log[TState](LogLevel logLevel, EventId eventId, TState state, Exception exception, Func`3 formatter)
at MyLibrary.Tests.MyClassTests.MyMethodTest() in D:\Source\Scratch\MyLibrary\MyLibrary.Tests\MyClassTests.cs:line 25
What am I doing wrong?
netcoreapp3.0 / Microsoft.Extensions.Logging 3.1.2 / NSubstitute 4.2.1
UPDATE: I have tried the match with Arg.Any<>() and get the same result:
logger.Received(1).Log(
Arg.Any<LogLevel>(),
Arg.Any<EventId>(),
Arg.Any<object>(),
Arg.Any<Exception>(),
Arg.Any<Func<object, Exception, string>>());
UPDATE 2: I have tried the same test using Moq and get the same result:
logger.Verify(l => l.Log(
LogLevel.Error,
It.IsAny<EventId>(),
It.Is<object>(o => o.ToString() == message),
null,
It.IsAny<Func<object, Exception, string>>()),
Times.Once);
Result:
Test method MyLibrary.Tests.Moq.MyClassTests.MyMethodTest threw exception:
Moq.MockException:
Expected invocation on the mock once, but was 0 times: l => l.Log<object>(LogLevel.Error, It.IsAny<EventId>(), It.Is<object>(o => o.ToString() == "a message"), null, It.IsAny<Func<object, Exception, string>>())
Performed invocations:
Mock<ILogger<MyClass>:1> (l):
ILogger.Log<FormattedLogValues>(LogLevel.Error, 0, a message, null, Func<FormattedLogValues, Exception, string>)
at Moq.Mock.Verify(Mock mock, LambdaExpression expression, Times times, String failMessage)
at Moq.Mock`1.Verify(Expression`1 expression, Times times)
at Moq.Mock`1.Verify(Expression`1 expression, Func`1 times)
at MyLibrary.Tests.Moq.MyClassTests.MyMethodTest() in D:\Source\Scratch\MyLibrary\MyLibrary.Tests.Moq\MyClassTests.cs:line 25
The main issue unit testing ILogger invocations with .NET Core 3.* is that FormattedLogValues was changed to internal, it complicates things.
The Moq workaround is to use It.IsAnyType:
public class TestsUsingMoq
{
[Test]
public void MyMethod_String_LogsError()
{
// Arrange
var logger = Mock.Of<ILogger<MyClass>>();
var myClass = new MyClass(logger);
var message = "a message";
// Act
myClass.MyMethod(message);
//Assert
Mock.Get(logger)
.Verify(l => l.Log(LogLevel.Error,
It.IsAny<EventId>(),
It.Is<It.IsAnyType>((o, t) => ((IReadOnlyList<KeyValuePair<string, object>>) o).Last().Value.ToString().Equals(message)),
It.IsAny<Exception>(),
(Func<It.IsAnyType, Exception, string>) It.IsAny<object>()),
Times.Once);
}
}
NSubstitute doesn't have an It.IsAnyType equivalent at the moment as far as I am aware, which presents an issue when trying to use the Received method. There is a workaround however as it does provide a ReceivedCalls method which you can iterate over and do you own invocation check.
public class TestsUsingNSubstitute
{
[Test]
public void MyMethod_String_LogsError()
{
// Arrange
var logger = Substitute.For<ILogger<MyClass>>();
var myClass = new MyClass(logger);
var message = "a message";
// Act
myClass.MyMethod(message);
//Assert
Assert.That(logger.ReceivedCalls()
.Select(call => call.GetArguments())
.Count(callArguments => ((LogLevel) callArguments[0]).Equals(LogLevel.Error) &&
((IReadOnlyList<KeyValuePair<string, object>>) callArguments[2]).Last().Value.ToString().Equals(message)),
Is.EqualTo(1));
}
}
As a workaround, it's not a bad one, and could be easily bundled up into an extension method.
FormattedLogValues implements IReadOnlyList<KeyValuePair<string, object>>. The last item in this list is the original message that you specified.
Working sample
I tried wrapping the Logger around an adapter, more like a proxy class.
You can mock the adapter interface and that would return what log function has been called.
public class LoggerAdapter<TType> : ILoggerAdapter<TType>
{
private readonly ILogger<TType> _logger;
public LoggerAdapter(ILogger<TType> logger)
{
_logger = logger;
}
public void LogInformation(string message, params object[] args)
{
_logger.LogInformation(message,args);
}
public void LogError(string message, params object[] args)
{
_logger.LogError(message, args);
}
}
private readonly ILoggerAdapter<PosUpdateService> _logger = Substitute.For<ILoggerAdapter<PosUpdateService>>();
_logger.Received(1).LogInformation("User with Id {id} was fetched in {0} milliseconds",
Arg.Is(Id),
Arg.Any<long>());
I am trying to write Unit test to the handler function, I followed the example from the Spring project. Can someone help me why the following test is throwing UnsupportedMediaTypeStatusException?
Thanks
Handler function
public Mono<ServerResponse> handle(ServerRequest serverRequest) {
log.info("{} Processing create request", serverRequest.exchange().getLogPrefix());
return ok().body(serverRequest.bodyToMono(Person.class).map(p -> p.toBuilder().id(UUID.randomUUID().toString()).build()), Person.class);
}
Test Class
#SpringBootTest
#RunWith(SpringRunner.class)
public class MyHandlerTest {
#Autowired
private MyHandler myHandler;
private ServerResponse.Context context;
#Before
public void createContext() {
HandlerStrategies strategies = HandlerStrategies.withDefaults();
context = new ServerResponse.Context() {
#Override
public List<HttpMessageWriter<?>> messageWriters() {
return strategies.messageWriters();
}
#Override
public List<ViewResolver> viewResolvers() {
return strategies.viewResolvers();
}
};
}
#Test
public void handle() {
Gson gson = new Gson();
MockServerWebExchange exchange = MockServerWebExchange.from(
MockServerHttpRequest.post("/api/create")
.body(gson.toJson(Person.builder().firstName("Jon").lastName("Doe").build())));
MockServerHttpResponse mockResponse = exchange.getResponse();
ServerRequest serverRequest = ServerRequest.create(exchange, HandlerStrategies.withDefaults().messageReaders());
Mono<ServerResponse> serverResponseMono = myHandler.handle(serverRequest);
Mono<Void> voidMono = serverResponseMono.flatMap(response -> {
assertThat(response.statusCode()).isEqualTo(HttpStatus.OK);
boolean condition = response instanceof EntityResponse;
assertThat(condition).isTrue();
return response.writeTo(exchange, context);
});
StepVerifier.create(voidMono)
.expectComplete().verify();
StepVerifier.create(mockResponse.getBody())
.consumeNextWith(a -> System.out.println(a))
.expectComplete().verify();
assertThat(mockResponse.getHeaders().getContentType()).isEqualTo(MediaType.APPLICATION_JSON);
}
}
Error Message:
java.lang.AssertionError: expectation "expectComplete" failed (expected: onComplete(); actual: onError(org.springframework.web.server.UnsupportedMediaTypeStatusException: 415 UNSUPPORTED_MEDIA_TYPE "Content type 'application/octet-stream' not supported for bodyType=com.example.demo.Person"))
I found that I missed .contentType(MediaType.APPLICATION_JSON) to my mock request.
MockServerWebExchange.from(
MockServerHttpRequest.post("/api/create").contentType(MediaType.APPLICATION_JSON)
.body(gson.toJson(Person.builder().firstName("Jon").lastName("Doe").build())));
fixed my issue.
I am writing unit tests for DocumentDBRepository but I got a null reference exception. I use Moq framework and XUnit.
Here's my methods in DocumentDBRepository class.
public class DocumentDBRepository<T> : IRepository<T> where T: class
{
private static string DatabaseId;
private static string CollectionId;
private static IDocumentClient client;
public DocumentDBRepository(IDocumentClient documentClient, string databaseId, string collectionId)
{
DatabaseId = databaseId;
CollectionId = collectionId;
client = documentClient;
CreateDatabaseIfNotExistsAsync().Wait();
CreateCollectionIfNotExistsAsync().Wait();
}
public async Task<IDocumentQuery<T>> GetQuery(Expression<Func<T, bool>> predicate)
{
try
{
IDocumentQuery<T> query = client.CreateDocumentQuery<T>(
UriFactory.CreateDocumentCollectionUri(DatabaseId, CollectionId),
new FeedOptions { MaxItemCount = -1, EnableCrossPartitionQuery = true })
.Where(predicate)
.AsDocumentQuery();
return query;
}
catch (Exception e) {
throw;
}
}
public async Task<IEnumerable<T>> GetEntities(IDocumentQuery<T> query)
{
try
{
List<T> results = new List<T>();
while (query.HasMoreResults)
{
results.AddRange(await query.ExecuteNextAsync<T>());
}
return results;
}
catch (Exception e)
{
throw;
}
}
}
Here's my test code:
public interface IFakeDocumentQuery<T> : IDocumentQuery<T>, IOrderedQueryable<T>
{
}
[Fact]
public async virtual Task Test_GetBooksById()
{
var expected = new List<Book> {
new Book { ID = "123", Description = "HarryPotter"},
new Book { ID = "124", Description = "HarryPotter2"} };
var response = new FeedResponse<Book>(expected);
var mockDocumentQuery = new Mock<IFakeDocumentQuery<Book>>();
mockDocumentQuery.SetupSequence(_ => _.HasMoreResults)
.Returns(true)
.Returns(false);
mockDocumentQuery.Setup(_ => _.ExecuteNextAsync<Book>(It.IsAny<CancellationToken>()))
.ReturnsAsync(response);
var client = new Mock<IDocumentClient>();
client.Setup(_ => _.CreateDocumentQuery<Book>(It.IsAny<Uri>(), It.IsAny<FeedOptions>()))
.Returns(mockDocumentQuery.Object);
var documentsRepository = new DocumentDBRepository<Book>(client.Object, "123", "123");
//Act
var query = await documentsRepository.GetQuery(t => t != null);
var entities = await documentsRepository.GetEntities(query);
//Assert
if (entities != null)
{
entities.Should().BeEquivalentTo(expected);
}
}
Here's the error message after running the test method:
Message: System.NullReferenceException : Object reference not set to
an instance of an object.
When I stepped through the code, the error happens right after the the test code called GetQuery() method:
IDocumentQuery<T> query = client.CreateDocumentQuery<T>(
UriFactory.CreateDocumentCollectionUri(DatabaseId, CollectionId),
new FeedOptions { MaxItemCount = -1, EnableCrossPartitionQuery = true })
.Where(predicate)
.AsDocumentQuery();
Here's my thought process: when I stepped through the entire code, I do not see any null variables. But in the 'response' variable from the second line of the test method, it does show a lot of the properties are null exception but result view shows the 'expected' variable.
My question is, is it because of the response variable that caused the null reference exception? Or somewhere else?
PS: Test code reference from here
I also tried turning on the Mock behavior to strict and saw this error message.
Message: System.AggregateException : One or more errors occurred.
(IDocumentClient.ReadDatabaseAsync(dbs/123, null) invocation failed
with mock behavior Strict. All invocations on the mock must have a
corresponding setup.)
---- Moq.MockException : IDocumentClient.ReadDatabaseAsync(dbs/123, null) invocation failed with mock behavior Strict. All invocations on
the mock must have a corresponding setup.
As suspected the problem is .Where(predicate). I ran a test with the provided example and removed the .Where clause and it executed to completion.
The fake interface inherits from both IOrderedQueryable and IDocumentQuery. The issue is that the Where is converting it back to a plain IEnumerable because of the List data source and the AsDocumentQuery is crapping out as it is expecting an IDocumentQuery
I am not a fan of tightly coupling to APIs I can't control. I would abstract my way around such implementation details for that very reason.
The work around involved having to provide a fake Linq IQueryProvider to bypass any queries and return a type that derives from IDocumentQuery so as to allow AsDocumentQuery to behave as intended.
But first I refactored GetEntities and made GetQuery private to stop the repository from being a leaky abstraction.
private IDocumentQuery<T> getQuery(Expression<Func<T, bool>> predicate) {
var uri = UriFactory.CreateDocumentCollectionUri(DatabaseId, CollectionId);
var feedOptions = new FeedOptions { MaxItemCount = -1, EnableCrossPartitionQuery = true };
var queryable = client.CreateDocumentQuery<T>(uri, feedOptions);
IQueryable<T> filter = queryable.Where(predicate);
IDocumentQuery<T> query = filter.AsDocumentQuery();
return query;
}
public async Task<IEnumerable<T>> GetEntities(Expression<Func<T, bool>> predicate) {
try {
IDocumentQuery<T> query = getQuery(predicate);
var results = new List<T>();
while (query.HasMoreResults) {
results.AddRange(await query.ExecuteNextAsync<T>());
}
return results;
} catch (Exception e) {
throw;
}
}
Note that getQuery is not doing anything async so it should not be returning a Task<> anyway.
Next in the test the mocked IDocumentQuery was set up to allow the test to flow to completion. This was done by providing a mocked IQueryProvider the would return the mocked IDocumentQuery when Linq queries are invoked against it. (which was the cause of the problem to begin with)
public async virtual Task Test_GetBooksById() {
//Arrange
var id = "123";
Expression<Func<Book, bool>> predicate = t => t.ID == id;
var dataSource = new List<Book> {
new Book { ID = id, Description = "HarryPotter"},
new Book { ID = "124", Description = "HarryPotter2"}
}.AsQueryable();
var expected = dataSource.Where(predicate);
var response = new FeedResponse<Book>(expected);
var mockDocumentQuery = new Mock<IFakeDocumentQuery<Book>>();
mockDocumentQuery
.SetupSequence(_ => _.HasMoreResults)
.Returns(true)
.Returns(false);
mockDocumentQuery
.Setup(_ => _.ExecuteNextAsync<Book>(It.IsAny<CancellationToken>()))
.ReturnsAsync(response);
var provider = new Mock<IQueryProvider>();
provider
.Setup(_ => _.CreateQuery<Book>(It.IsAny<System.Linq.Expressions.Expression>()))
.Returns((Expression expression) => {
if (expression != null) {
dataSource = dataSource.Provider.CreateQuery<Book>(expression);
}
mockDocumentQuery.Object;
});
mockDocumentQuery.As<IQueryable<Book>>().Setup(x => x.Provider).Returns(provider.Object);
mockDocumentQuery.As<IQueryable<Book>>().Setup(x => x.Expression).Returns(() => dataSource.Expression);
mockDocumentQuery.As<IQueryable<Book>>().Setup(x => x.ElementType).Returns(() => dataSource.ElementType);
mockDocumentQuery.As<IQueryable<Book>>().Setup(x => x.GetEnumerator()).Returns(() => dataSource.GetEnumerator());
var client = new Mock<IDocumentClient>();
client.Setup(_ => _.CreateDocumentQuery<Book>(It.IsAny<Uri>(), It.IsAny<FeedOptions>()))
.Returns(mockDocumentQuery.Object);
var documentsRepository = new DocumentDBRepository<Book>(client.Object, "123", "123");
//Act
var entities = await documentsRepository.GetEntities(predicate);
//Assert
entities.Should()
.NotBeNullOrEmpty()
.And.BeEquivalentTo(expected);
}
This allowed the test to be exercised to completion, behave as expected, and pass the test.
Currently, whenever I need to fail a test in response to an exception thrown in another thread, I write something like this:
package com.example;
import java.util.ArrayList;
import java.util.List;
import org.testng.annotations.Test;
import static java.util.Arrays.asList;
import static java.util.Collections.synchronizedList;
import static org.testng.Assert.fail;
public final class T {
#Test
public void testFailureFromLambda() throws Throwable {
final List<Throwable> errors = synchronizedList(new ArrayList<>());
asList("0", "1", "2").parallelStream().forEach(s -> {
try {
/*
* The actual code under test here.
*/
throw new Exception("Error " + s);
} catch (final Throwable t) {
errors.add(t);
}
});
if (!errors.isEmpty()) {
errors.forEach(Throwable::printStackTrace);
final Throwable firstError = errors.iterator().next();
fail(firstError.getMessage(), firstError);
}
}
}
A synchronized list may be replaced with an AtomicReference<Throwable>, but in general the code remains pretty much the same.
Is there any standard (and less verbose) way of doing the same using any of test frameworks available in Java (TestNG, JUnit, Hamcrest, AssertJ, etc.)?
By default TestNG fails a test method when an exception is thrown from it. I believe the same thing happens with JUnit as well, wherein it marks a test as errored, if it throws an unexpected exception.
If you are to be dealing with Streams, then you would need to wrap it up within a RuntimeException variant, so that Java doesn't complain. TestNG would automatically fail the test.
Here's a sample :
#Test
public void testFailureFromLambdaRefactored() {
asList("0", "1", "2").parallelStream().forEach(s -> {
try {
/*
* The actual code under test here.
*/
if (s.equals("2")) {
throw new Exception("Error " + s);
}
} catch (final Throwable t) {
throw new RuntimeException(t);
}
});
}
This was for scenarios that involve lambdas and streams. In general if you would like to know about an exception that happens in a new thread spun off from a #Test method, then you would need to use ExecutorService.
Here's a sample :
#Test
public void testFailureInAnotherThread() throws InterruptedException, ExecutionException {
List<String> list = asList("0", "1", "2");
ExecutorService service = Executors.newFixedThreadPool(2);
List<Future<Void>> futures = service.invokeAll(Arrays.asList(new Worker(list)));
for (Future future : futures) {
future.get();
}
}
public static class Worker implements Callable<Void> {
private List<String> list;
public Worker(List<String> list) {
this.list = list;
}
#Override
public Void call() throws Exception {
for (String s : list) {
if (s.equals("2")) {
throw new Exception("Error " + s);
}
}
return null;
}
}
I have this simple Saga in Rebus:
public void MySaga : Saga<MySagaData>
IAmInitiatedBy<Event1>
IHandleMessages<Event2>
{
private IBus bus;
private ILog logger;
public MySaga(IBus bus, ILog logger)
{
if (bus == null) throw new ArgumentNullException("bus");
if (logger == null) throw new ArgumentNullException("logger");
this.bus = bus;
this.logger = logger;
}
protected override void CorrelateMessages(ICorrelationConfig<MySagaData> config)
{
config.Correlate<Event>(m => m.MyObjectId.Id, s => s.Id);
config.Correlate<Event>(m => m.MyObjectId.Id, s => s.Id);
}
public Task Handle(Event1 message)
{
return Task.Run(() =>
{
this.Data.Id = message.MyObjectId.Id;
this.Data.State = MyEnumSagaData.Step1;
var cmd = new ResponseCommandToEvent1(message.MyObjectId);
bus.Send(cmd);
});
}
public Task Handle(Event2 message)
{
return Task.Run(() =>
{
this.Data.State = MyEnumSagaData.Step2;
var cmd = new ResponseCommandToEvent2(message.MyObjectId);
bus.Send(cmd);
});
}
}
and thanks to the kind mookid8000 I can test the saga using FakeBus and a SagaFixture:
[TestInitialize]
public void TestInitialize()
{
var log = new Mock<ILog>();
bus = new FakeBus();
fixture = SagaFixture.For<MySaga>(() => new MySaga(bus, log.Object));
idTest = new MyObjectId(Guid.Parse("1B2E7286-97E5-4978-B5B0-D288D71AD670"));
}
[TestMethod]
public void TestIAmInitiatedBy()
{
evt = new Event1(idTest);
fixture.Deliver(evt);
var testableFixture = fixture.Data.OfType<MySagaData>().First();
Assert.AreEqual(MyEnumSagaData.Step1, testableFixture.State);
// ... more asserts
}
[TestMethod]
public void TestIHandleMessages()
{
evt = new Event2(idTest);
fixture.Deliver(evt);
var testableFixture = fixture.Data.OfType<MySagaData>().First();
Assert.AreEqual(MyEnumSagaData.Step2, testableFixture.State);
// ... more asserts
}
[TestCleanup]
public void TestCleanup()
{
fixture.Dispose();
bus.Dispose();
}
The first test method that check IAmInitiatedBy is correctly executed and no error is thrown, while the second test fail. It looks like a correlation issues since fixture.Data contains no elements and in fixture.LogEvents contains as last elements this error: Could not find existing saga data for message Event2/b91d161b-eb1b-419d-9576-2c13cd9d9c51.
What is this GUID? Is completly different from the one I defined in the unit test? Any ideas? Is legal what I'm tryng to test (since I'm using an in-memory bus)?
This line is bad: this.Data.Id = message.MyObjectId.Id. If you checked the value of Data.Id before you overwrote it, you would have noticed that the property already had a value.
You do not assign the saga ID - Rebus does that. And you should leave that property alone :)
Regarding your error - when Rebus wants to log information about a specific message, it logs a short name for the type and the message ID, i.e. the value of the automatically-assigned rbs2-msg-id header. In other words: It's not the value of the property m.MyObjectId.Id, you're seeing, it's the message ID.
Since the saga fixture is re-initialized for every test run, and you only deliver an Event2 to it (which is not allowed to initiate a new instance), the saga will not be hit.