I'm developing an API which communicates with MongoDB and I need to create some statistics from one collection. I have the following service:
public class BoxService : IBoxService
{
private readonly IMongoCollection<Box> _boxCollection;
public BoxService(IOptions<DbSettings> dbSettings, IMongoClient mongoClient)
{
var mongoDatabase = mongoClient.GetDatabase(dbSettings.Value.DatabaseName);
_boxCollection = mongoDatabase.GetCollection<Box>(dbSettings.Value.BoxCollectionName);
}
public async Task<List<BoxStatisticsDto>> GetBoxNumberStatisticsAsync()
{
var boxNumberStatisticsList = new List<BoxStatisticsDto>();
var results = await _boxCollection.AsQueryable()
.Select(box => new { box.WarehouseId, Content = box.Content ?? string.Empty })
.ToListAsync();
// More calculations with the results list
return boxNumberStatisticsList;
}
}
And the following test:
public class BoxServiceTest
{
private readonly IMongoCollection<Box> _boxCollection;
private readonly List<Box> _boxes;
private readonly IBoxService _boxService;
public BoxServiceTest()
{
_boxCollection = A.Fake<IMongoCollection<Box>>();
_boxes = new List<Box> {...};
var mockOptions = A.Fake<IOptions<DbSettings>>();
var mongoClient = A.Fake<IMongoClient>();
var mongoDb = A.Fake<IMongoDatabase>();
A.CallTo(() => mongoClient.GetDatabase(A<string>._, default)).Returns(mongoDb);
A.CallTo(() => mongoDb.GetCollection<Box>(A<string>._, default)).Returns(_boxCollection);
_boxService = new BoxService(mockOptions, mongoClient);
}
}
This is working so far, the BoxService is created with the fake parameters and I can test other functionalities of the service (FindAll, FindById, Create, etc.) but how can I test the GetBoxNumberStatisticsAsync function? I can't fake the AsQueryable because it's an extension method.
As you've noted, you can't fake an extension method. This question is asked every once in a while. For example, see Faking an Extension Method in a 3rd Party Library. There are a few approaches:
if the static method is simple enough, to divine what it does and fake the non-static methods that it calls
add a layer of indirection: wrap the call to the extension method in an interface that you can fake
don't fake the database. Instead, replace it with some in-memory analogue, if one exists (I don't know what's available for Mongo)
Here is what I ended up with. A base interface for all my services:
public interface IBaseService<T>
{
//generic method definitions for all services: Findall, FindById, Create, Update
}
An abstract class to have a generic constructor:
public abstract class BaseService<T> : IBaseService<T>
{
protected BaseService(IOptions<DbSettings> dbSettings, IMongoClient mongoClient, string collectionName)
{
var mongoDatabase = mongoClient.GetDatabase(dbSettings.Value.DatabaseName);
Collection = mongoDatabase.GetCollection<T>(collectionName);
}
protected IMongoCollection<T> Collection { get; }
// abstract method definitions for IBaseService stuff
public virtual async Task<List<T>> CollectionToListAsync()
{
return await Collection.AsQueryable().ToListAsync();
}
}
An interface for my BoxService:
public interface IBoxService : IBaseService<Box>
{
public Task<List<BoxStatisticsDto>> GetBoxNumberStatisticsAsync();
}
The service itself:
public class BoxService : BaseService<Box>, IBoxService
{
public BoxService(IOptions<DbSettings> dbSettings, IMongoClient mongoClient)
: base(dbSettings, mongoClient, dbSettings.Value.BoxCollectionName)
{
}
public async Task<List<BoxStatisticsDto>> GetBoxNumberStatisticsAsync()
{
var boxNumberStatisticsList = new List<BoxStatisticsDto>();
var list = await CollectionToListAsync();
var results = list.Select(box => new { box.WarehouseId, Content = box.Content ?? string.Empty }).ToList();
//...
return boxNumberStatisticsList;
}
}
And finally the test:
public async Task GetBoxNumberStatisticsAsync_ReturnsStatistics()
{
// Arrange
var expected = new List<BoxStatisticsDto> {...};
var fakeService = A.Fake<BoxService>(options => options.CallsBaseMethods());
A.CallTo(() => fakeService.CollectionToListAsync()).Returns(_boxes);
// Act
var boxList = await ((IBoxService)fakeService).GetBoxNumberStatisticsAsync();
// Assert
}
I'm not a huge fan of making the CollectionToListAsync public, but nothing really worked for me here. I tried creating IQueryable and IEnumerable from my list and convert them to IMongoQueryable but no success. I also tried faking the IMongoQueryable but I couldn't execute the Select on it as it gave an error that the 'collectionNamespace' can't be null and the CollectionNamespace can't be faked, because it's a sealed class.
The original problem I have is that I am writing an integration test for which I want to spoof one small value returned from an IDbConnection instance. I don't want to have to spoof return values for every query. Instead I want all queries to actually hit the database and be processed normally, but for one SELECT I want to tweak the values. I envision it as a man-in-the-middle type of modification for a SELECT query.
I am using the Moq library and perhaps what I am trying to do is not possible. Here's a generic example of what I have tried for a made up interface (the 3rd attempt works but requires me to manually write a wrapper class that am hoping can be avoided):
using Moq;
using System;
namespace ConsoleApp1
{
public interface IProcess
{
string Process1<T>(T t);
string Process2<T, TA>(T t, TA ta);
}
public class Processor : IProcess
{
private Processor() { }
public static Processor CreateProcessorFactoryMethod() { return new Processor(); }
public string Process1<T>(T t) => "Processor.Process1";
public string Process2<T, TA>(T t, TA ta) => "Processor.Process2";
}
public class Program
{
static void Main(string[] args)
{
IProcess existingProcessorInstance = Processor.CreateProcessorFactoryMethod();
IProcess objectToTest = null;
Mock<IProcess> mock = null;
int attemptNumber = 3; //set this to the attempt you wish to try
switch (attemptNumber)
{
case 1: //This doesn't work. First argument is actually a constructor parameter, but I want it to be the underlying instance to use.
mock = new Mock<IProcess>(existingProcessorInstance, MockBehavior.Loose);
objectToTest = mock.Object;
break;
case 2: //This also doesn't work. It thinks the first parameter is a parameter for the Processor constructor, but I want it to be the underlying instance to use.
var mockProcessor = new Mock<Processor>(existingProcessorInstance) { CallBase = true};
objectToTest = mockProcessor.Object;
break;
case 3:
//this works, but I have to write a whole new Wrapper class for each interface I need to do this for, which is kind of a pain.
var wrapper = new WrapperForIProcess(existingProcessorInstance);
mock = wrapper.Mockery;
objectToTest = wrapper;
break;
default:
throw new NotImplementedException();
}
//I want to mock this one specific call, but everything else should go through to the existingProcessorInstance.
mock.Setup(m => m.Process1<string>(It.Is<string>(s => s == string.Empty)))
.Returns((string t) => "Mock of Process1");
Console.WriteLine(objectToTest.Process1<string>(string.Empty)); //expect: "Mock of Process1"
Console.WriteLine(objectToTest.Process1<string>("asdf")); //expect: "Processor.Process1"
Console.WriteLine(objectToTest.Process2<int, double>(42, 1.0)); //expect: "Processor.Process2"
}
/// <summary>
/// Created for attempt #3
/// </summary>
public class WrapperForIProcess : IProcess
{
private readonly IProcess _processor;
public WrapperForIProcess(IProcess processor)
{
_processor = processor;
Mockery = new Mock<IProcess>(MockBehavior.Strict);
}
public Mock<IProcess> Mockery { get; }
public string Process1<T>(T t) => WrapFunctionCall<string>(() => Mockery.Object.Process1(t), () => _processor.Process1(t));
public string Process2<T, TA>(T t, TA ta) => WrapFunctionCall<string>(()=>Mockery.Object.Process2(t, ta), ()=>_processor.Process2(t,ta));
private static T WrapFunctionCall<T>(Func<T> mockFunction, Func<T> wrappedObjectFunction)
{
try
{
return mockFunction.Invoke();
}
catch(MockException)
{
//assuming this is thrown due to no implementation provided in the mock (and strict behavior)
//so fall back to the behavior of the object we are wrapping.
return wrappedObjectFunction.Invoke();
}
}
}
}
}
Is there a better approach I should be taking? Is this even possible with Moq?
I've a class with several services injected in its constructor. I'm using Autofixture with xUnit.net and NSubstitute, and created an attribute to setup the global customization.
public class AutoDbDataAttribute : AutoDataAttribute
{
public AutoDbDataAttribute() : base(() => new Fixture().Customize(new AutoNSubstituteCustomization()))
{
}
public AutoDbDataAttribute(Type customizationType) : base(() =>
{
var customization = Activator.CreateInstance(customizationType) as ICustomization;
var fixture = new Fixture();
fixture.Customize(new AutoNSubstituteCustomization());
fixture.Customize(customization);
return fixture;
})
{
}
}
I also have a custom customization class that setups the common customization for the test methods in the same class.
public class RevenueProviderCustomization : ICustomization
{
public void Customize(IFixture fixture)
{
fixture.Register<IRevenueContextService>(() =>
{
var contextService = Substitute.For<IRevenueContextService>();
contextService.GetContext().Returns(fixture.Create<RevenueContext>());
return contextService;
});
fixture.Register<ICompanyService>(() =>
{
var companyService = Substitute.For<ICompanyService>();
companyService.Get(Arg.Any<Guid>()).Returns(fixture.Create<Company>());
return companyService;
});
}
}
Now, some of my tests depend on modifying specific properties in the objects returned by the services. So in some cases, I want to modify the RevenueContext and in some cases, I want to modify the Company data.
What I did was creating another object inside the test itself and modify the Returns of the service with the new object, like this:
[Theory]
[AutoDbData(typeof(RevenueProviderCustomization))]
public void ShouldReturnCompanyRevenue(RevenueProvider sut, Company company, [Frozen]IRevenueContextService contextService)
{
var fixture = new Fixture();
RevenueContext context = fixture.Build<RevenueContext>().With(c => c.DepartmentId, null).Create();
contextService.GetContext().Returns(context);
sut.GetRevenue().Should().Be(company.Revenue);
}
But this doesn't work. The RevenueContext from the RevenueProviderCustomization is still used.
Does anyone know how I can override the return from the service? I don't want to setup the fixture one by one in my test, so I was hoping to be able to create a 'general setup' and modify as needed according to the test case.
UPDATE 1
Trying the answer from Mark, I changed the test to
[Theory]
[AutoDbData(typeof(RevenueProviderCustomization))]
public void ShouldReturnCompanyRevenue([Frozen]IRevenueContextService contextService, [Frozen]Company company, RevenueProvider sut, RevenueContext context)
{
context.DepartmentId = null;
contextService.GetContext().Returns(context);
sut.GetRevenue().Should().Be(company.Revenue);
}
The problem is because the RevenueContext is called in the RevenueProvider constructor. So my modification to the DepartmentId happens after the call was made.
public RevenueProvider(IRevenueContextService contextService, ICompanyService companyService)
{
_contextService = contextService;
_companyService = companyService;
_company = GetCompany();
}
public double GetRevenue()
{
if (_hasDepartmentContext)
return _company.Departments.Single(d => d.Id == _departmentId).Revenue;
else
return _company.Revenue;
}
private Company GetCompany()
{
RevenueContext context = _contextService.GetContext();
if (context.DepartmentId.HasValue)
{
_hasDepartmentContext = true;
_departmentId = context.DepartmentId.Value;
}
return _companyService.Get(context.CompanyId);
}
Assuming that RevenueProvider essentially looks like this:
public class RevenueProvider
{
private readonly ICompanyService companySvc;
public RevenueProvider(ICompanyService companySvc)
{
this.companySvc = companySvc;
}
public object GetRevenue()
{
var company = this.companySvc.Get(Guid.Empty);
return company.Revenue;
}
}
Then the following test passes:
[Theory]
[AutoDbData(typeof(RevenueProviderCustomization))]
public void ShouldReturnCompanyRevenue(
[Frozen]ICompanyService companySvc,
RevenueProvider sut,
Company company)
{
companySvc.Get(Arg.Any<Guid>()).Returns(company);
var actual = sut.GetRevenue();
Assert.Equal(company.Revenue, actual);
}
This scenario is exactly what the [Frozen] attribute is designed to handle. The various attributes that AutoFixture defines are applied in the order of the arguments. This is by design, because it enables you to pull out a few values from the argument list before you freeze a type.
In the OP, [Frozen] is only applied after sut, which is the reason the configuration of the mock doesn't apply within the SUT.
TL;DR - I'm looking for xUnit's equivalent of MSTest's AssemblyInitialize (aka the ONE feature it has that I like).
Specifically I'm looking for it because I have some Selenium smoke tests which I would like to be able to run with no other dependencies. I have a Fixture that will launch IisExpress for me and kill it on disposal. But doing this before every test hugely bloats runtime.
I would like to trigger this code once at the start of testing, and dispose of it (shutting down the process) at the end. How could I go about doing that?
Even if I can get programmatic access to something like "how many tests are currently being run" I can figure something out.
As of Nov 2015 xUnit 2 is out, so there is a canonical way to share features between tests. It is documented here.
Basically you'll need to create a class doing the fixture:
public class DatabaseFixture : IDisposable
{
public DatabaseFixture()
{
Db = new SqlConnection("MyConnectionString");
// ... initialize data in the test database ...
}
public void Dispose()
{
// ... clean up test data from the database ...
}
public SqlConnection Db { get; private set; }
}
A dummy class bearing the CollectionDefinition attribute.
This class allows Xunit to create a test collection, and will use the given fixture for all test classes of the collection.
[CollectionDefinition("Database collection")]
public class DatabaseCollection : ICollectionFixture<DatabaseFixture>
{
// This class has no code, and is never created. Its purpose is simply
// to be the place to apply [CollectionDefinition] and all the
// ICollectionFixture<> interfaces.
}
Then you need to add the collection name over all your test classes.
The test classes can receive the fixture through the constructor.
[Collection("Database collection")]
public class DatabaseTestClass1
{
DatabaseFixture fixture;
public DatabaseTestClass1(DatabaseFixture fixture)
{
this.fixture = fixture;
}
}
It's a bit more verbose than MsTests AssemblyInitialize since you have to declare on each test class which test collection it belongs, but it's also more modulable (and with MsTests you still need to put a TestClass on your classes)
Note: the samples have been taken from the documentation.
To execute code on assembly initialize, then one can do this (Tested with xUnit 2.3.1)
using Xunit.Abstractions;
using Xunit.Sdk;
[assembly: Xunit.TestFramework("MyNamespace.MyClassName", "MyAssemblyName")]
namespace MyNamespace
{
public class MyClassName : XunitTestFramework
{
public MyClassName(IMessageSink messageSink)
:base(messageSink)
{
// Place initialization code here
}
public new void Dispose()
{
// Place tear down code here
base.Dispose();
}
}
}
See also https://github.com/xunit/samples.xunit/tree/master/AssemblyFixtureExample
Create a static field and implement a finalizer.
You can use the fact that xUnit creates an AppDomain to run your test assembly and unloads it when it's finished. Unloading the app domain will cause the finalizer to run.
I am using this method to start and stop IISExpress.
public sealed class ExampleFixture
{
public static ExampleFixture Current = new ExampleFixture();
private ExampleFixture()
{
// Run at start
}
~ExampleFixture()
{
Dispose();
}
public void Dispose()
{
GC.SuppressFinalize(this);
// Run at end
}
}
Edit: Access the fixture using ExampleFixture.Current in your tests.
It's not possible to do in the framework today. This is a feature planned for 2.0.
In order to make this work before 2.0, it would require you to perform significant re-architecture on the framework, or write your own runners that recognized your own special attributes.
I use AssemblyFixture (NuGet).
What it does is it provides an IAssemblyFixture<T> interface that is replacing any IClassFixture<T> where you want the object's lifetime to be as the testing assembly.
Example:
public class Singleton { }
public class TestClass1 : IAssemblyFixture<Singleton>
{
readonly Singletone _Singletone;
public TestClass1(Singleton singleton)
{
_Singleton = singleton;
}
[Fact]
public void Test1()
{
//use singleton
}
}
public class TestClass2 : IAssemblyFixture<Singleton>
{
readonly Singletone _Singletone;
public TestClass2(Singleton singleton)
{
//same singleton instance of TestClass1
_Singleton = singleton;
}
[Fact]
public void Test2()
{
//use singleton
}
}
I was quite annoyed for not having the option to execute things at the end of all the xUnit tests. Some of the options here are not as great, as they involve changing all your tests or putting them under one collection (meaning they get executed synchronously). But Rolf Kristensen's answer gave me the needed information to get to this code. It's a bit long, but you only need to add it into your test project, no other code changes necessary:
using Siderite.Tests;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Reflection;
using System.Text;
using Xunit;
using Xunit.Abstractions;
using Xunit.Sdk;
[assembly: TestFramework(
SideriteTestFramework.TypeName,
SideriteTestFramework.AssemblyName)]
namespace Siderite.Tests
{
public class SideriteTestFramework : ITestFramework
{
public const string TypeName = "Siderite.Tests.SideriteTestFramework";
public const string AssemblyName = "Siderite.Tests";
private readonly XunitTestFramework _innerFramework;
public SideriteTestFramework(IMessageSink messageSink)
{
_innerFramework = new XunitTestFramework(messageSink);
}
public ISourceInformationProvider SourceInformationProvider
{
set
{
_innerFramework.SourceInformationProvider = value;
}
}
public void Dispose()
{
_innerFramework.Dispose();
}
public ITestFrameworkDiscoverer GetDiscoverer(IAssemblyInfo assembly)
{
return _innerFramework.GetDiscoverer(assembly);
}
public ITestFrameworkExecutor GetExecutor(AssemblyName assemblyName)
{
var executor = _innerFramework.GetExecutor(assemblyName);
return new SideriteTestExecutor(executor);
}
private class SideriteTestExecutor : ITestFrameworkExecutor
{
private readonly ITestFrameworkExecutor _executor;
private IEnumerable<ITestCase> _testCases;
public SideriteTestExecutor(ITestFrameworkExecutor executor)
{
this._executor = executor;
}
public ITestCase Deserialize(string value)
{
return _executor.Deserialize(value);
}
public void Dispose()
{
_executor.Dispose();
}
public void RunAll(IMessageSink executionMessageSink, ITestFrameworkDiscoveryOptions discoveryOptions, ITestFrameworkExecutionOptions executionOptions)
{
_executor.RunAll(executionMessageSink, discoveryOptions, executionOptions);
}
public void RunTests(IEnumerable<ITestCase> testCases, IMessageSink executionMessageSink, ITestFrameworkExecutionOptions executionOptions)
{
_testCases = testCases;
_executor.RunTests(testCases, new SpySink(executionMessageSink, this), executionOptions);
}
internal void Finished(TestAssemblyFinished executionFinished)
{
// do something with the run test cases in _testcases and the number of failed and skipped tests in executionFinished
}
}
private class SpySink : IMessageSink
{
private readonly IMessageSink _executionMessageSink;
private readonly SideriteTestExecutor _testExecutor;
public SpySink(IMessageSink executionMessageSink, SideriteTestExecutor testExecutor)
{
this._executionMessageSink = executionMessageSink;
_testExecutor = testExecutor;
}
public bool OnMessage(IMessageSinkMessage message)
{
var result = _executionMessageSink.OnMessage(message);
if (message is TestAssemblyFinished executionFinished)
{
_testExecutor.Finished(executionFinished);
}
return result;
}
}
}
}
The highlights:
assembly: TestFramework instructs xUnit to use your framework, which
proxies to the default one
SideriteTestFramework also wraps the executor into a custom class
that then wraps the message sink
in the end, the Finished method is executed, with the list of tests
run and the result from the xUnit message
More work could be done here. If you want to execute stuff without caring about the tests run, you could inherit from XunitTestFramework and just wrap the message sink.
You can use IUseFixture interface to make this happen. Also all of your test must inherit TestBase class. You can also use OneTimeFixture directly from your test.
public class TestBase : IUseFixture<OneTimeFixture<ApplicationFixture>>
{
protected ApplicationFixture Application;
public void SetFixture(OneTimeFixture<ApplicationFixture> data)
{
this.Application = data.Fixture;
}
}
public class ApplicationFixture : IDisposable
{
public ApplicationFixture()
{
// This code run only one time
}
public void Dispose()
{
// Here is run only one time too
}
}
public class OneTimeFixture<TFixture> where TFixture : new()
{
// This value does not share between each generic type
private static readonly TFixture sharedFixture;
static OneTimeFixture()
{
// Constructor will call one time for each generic type
sharedFixture = new TFixture();
var disposable = sharedFixture as IDisposable;
if (disposable != null)
{
AppDomain.CurrentDomain.DomainUnload += (sender, args) => disposable.Dispose();
}
}
public OneTimeFixture()
{
this.Fixture = sharedFixture;
}
public TFixture Fixture { get; private set; }
}
EDIT: Fix the problem that new fixture create for each test class.
Does your build tool provide such a feature?
In the Java world, when using Maven as a build tool, we use the appropriate phases of the build lifecycle. E.g. in your case (acceptance tests with Selenium-like tools), one can make good use of the pre-integration-test and post-integration-test phases to start/stop a webapp before/after one's integration-tests.
I'm pretty sure the same mechanism can be set up in your environment.
The method described by Jared Kells
does not work under Net Core, because, well it is not guaranteed that finalizers will be called. And, in fact, it is not called for the code above. Please, see:
Why does the Finalize/Destructor example not work in .NET Core?
https://github.com/dotnet/runtime/issues/16028
https://github.com/dotnet/runtime/issues/17836
https://github.com/dotnet/runtime/issues/24623
So, based on the great answer above, here is what I ended up doing (replace saving to file as necessary):
public class DatabaseCommandInterceptor : IDbCommandInterceptor
{
private static ConcurrentDictionary<DbCommand, DateTime> StartTime { get; } = new();
public void ReaderExecuted(DbCommand command, DbCommandInterceptionContext<DbDataReader> interceptionContext) => Log(command, interceptionContext);
public void NonQueryExecuted(DbCommand command, DbCommandInterceptionContext<int> interceptionContext) => Log(command, interceptionContext);
public void ScalarExecuted(DbCommand command, DbCommandInterceptionContext<object> interceptionContext) => Log(command, interceptionContext);
private static void Log<T>(DbCommand command, DbCommandInterceptionContext<T> interceptionContext)
{
var parameters = new StringBuilder();
foreach (DbParameter param in command.Parameters)
{
if (parameters.Length > 0) parameters.Append(", ");
parameters.Append($"{param.ParameterName}:{param.DbType} = {param.Value}");
}
var data = new DatabaseCommandInterceptorData
{
CommandText = command.CommandText,
CommandType = $"{command.CommandType}",
Parameters = $"{parameters}",
Duration = StartTime.TryRemove(command, out var startTime) ? DateTime.Now - startTime : TimeSpan.Zero,
Exception = interceptionContext.Exception,
};
DbInterceptorFixture.Current.LogDatabaseCall(data);
}
public void NonQueryExecuting(DbCommand command, DbCommandInterceptionContext<int> interceptionContext) => OnStart(command);
public void ReaderExecuting(DbCommand command, DbCommandInterceptionContext<DbDataReader> interceptionContext) => OnStart(command);
public void ScalarExecuting(DbCommand command, DbCommandInterceptionContext<object> interceptionContext) => OnStart(command);
private static void OnStart(DbCommand command) => StartTime.TryAdd(command, DateTime.Now);
}
public class DatabaseCommandInterceptorData
{
public string CommandText { get; set; }
public string CommandType { get; set; }
public string Parameters { get; set; }
public TimeSpan Duration { get; set; }
public Exception Exception { get; set; }
}
/// <summary>
/// All times are in milliseconds.
/// </summary>
public record DatabaseCommandStatisticalData
{
public string CommandText { get; }
public int CallCount { get; init; }
public int ExceptionCount { get; init; }
public double Min { get; init; }
public double Max { get; init; }
public double Mean { get; init; }
public double StdDev { get; init; }
public DatabaseCommandStatisticalData(string commandText)
{
CommandText = commandText;
CallCount = 0;
ExceptionCount = 0;
Min = 0;
Max = 0;
Mean = 0;
StdDev = 0;
}
/// <summary>
/// Calculates k-th moment for n + 1 values: M_k(n + 1)
/// based on the values of k, n, mkn = M_k(N), and x(n + 1).
/// The sample adjustment (replacement of n -> (n - 1)) is NOT performed here
/// because it is not needed for this function.
/// Note that k-th moment for a vector x will be calculated in Wolfram as follows:
/// Sum[x[[i]]^k, {i, 1, n}] / n
/// </summary>
private static double MknPlus1(int k, int n, double mkn, double xnp1) =>
(n / (n + 1.0)) * (mkn + (1.0 / n) * Math.Pow(xnp1, k));
public DatabaseCommandStatisticalData Updated(DatabaseCommandInterceptorData data) =>
CallCount == 0
? this with
{
CallCount = 1,
ExceptionCount = data.Exception == null ? 0 : 1,
Min = data.Duration.TotalMilliseconds,
Max = data.Duration.TotalMilliseconds,
Mean = data.Duration.TotalMilliseconds,
StdDev = 0.0,
}
: this with
{
CallCount = CallCount + 1,
ExceptionCount = ExceptionCount + (data.Exception == null ? 0 : 1),
Min = Math.Min(Min, data.Duration.TotalMilliseconds),
Max = Math.Max(Max, data.Duration.TotalMilliseconds),
Mean = MknPlus1(1, CallCount, Mean, data.Duration.TotalMilliseconds),
StdDev = Math.Sqrt(
MknPlus1(2, CallCount, Math.Pow(StdDev, 2) + Math.Pow(Mean, 2), data.Duration.TotalMilliseconds)
- Math.Pow(MknPlus1(1, CallCount, Mean, data.Duration.TotalMilliseconds), 2)),
};
public static string Header { get; } =
string.Join(TextDelimiter.VerticalBarDelimiter.Key,
new[]
{
nameof(CommandText),
nameof(CallCount),
nameof(ExceptionCount),
nameof(Min),
nameof(Max),
nameof(Mean),
nameof(StdDev),
});
public override string ToString() =>
string.Join(TextDelimiter.VerticalBarDelimiter.Key,
new[]
{
$"\"{CommandText.Replace("\"", "\"\"")}\"",
$"{CallCount}",
$"{ExceptionCount}",
$"{Min}",
$"{Max}",
$"{Mean}",
$"{StdDev}",
});
}
public class DbInterceptorFixture
{
public static readonly DbInterceptorFixture Current = new();
private bool _disposedValue;
private ConcurrentDictionary<string, DatabaseCommandStatisticalData> DatabaseCommandData { get; } = new();
private static IMasterLogger Logger { get; } = new MasterLogger(typeof(DbInterceptorFixture));
/// <summary>
/// Will run once at start up.
/// </summary>
private DbInterceptorFixture()
{
AssemblyLoadContext.Default.Unloading += Unloading;
}
/// <summary>
/// A dummy method to call in order to ensure that static constructor is called
/// at some more or less controlled time.
/// </summary>
public void Ping()
{
}
public void LogDatabaseCall(DatabaseCommandInterceptorData data) =>
DatabaseCommandData.AddOrUpdate(
data.CommandText,
_ => new DatabaseCommandStatisticalData(data.CommandText).Updated(data),
(_, d) => d.Updated(data));
private void Unloading(AssemblyLoadContext context)
{
if (_disposedValue) return;
GC.SuppressFinalize(this);
_disposedValue = true;
SaveData();
}
private void SaveData()
{
try
{
File.WriteAllLines(
#"C:\Temp\Test.txt",
DatabaseCommandData
.Select(e => $"{e.Value}")
.Prepend(DatabaseCommandStatisticalData.Header));
}
catch (Exception e)
{
Logger.LogError(e);
}
}
}
and then register DatabaseCommandInterceptor once somewhere in the tests:
DbInterception.Add(new DatabaseCommandInterceptor());
I also prefer calling DbInterceptorFixture.Current.Ping() in the base test class, though I don't think that this is needed.
The interface IMasterLogger is just a strongly typed wrapper around log4net, so just replace it with your favorite one.
The value of TextDelimiter.VerticalBarDelimiter.Key is just '|' and it sits in what we call a closed set.
PS If I screwed up with statistics, please, comment and I will update the answer.
Just use the static constructor, that's all you need to do, it runs just once.
I have a class that does some retrieving of contents, and it has a method that requires some inputs (filters) before retrieving it. One of the "input" calls another method, which basically returning an int, how do I mock it using MOQ? Here's an example:
namespace MyNamespace
{
public class ConfigMetaDataColumns : MyModel
{
public int FieldID { get { return ValueInt("FieldID"); } }
public int OrderId { get { return ValueInt("OrderId"); } }
public string Label { get { return ValueString("Label"); } }
public string FieldName { get { return ValueString("FieldName"); } }
public int IsReadOnly { get { return ValueInt("IsReadOnly"); } }
}
public class GetDataClass
{
protected OpenSQLAccessLayer m_WITObject;
// Input Properties
public string GroupID;
public string PageName;
// Output Properties
/// <summary>
/// Get Config meta data
/// </summary>
/// <returns></returns>
public IEnumerable<ConfigMetaDataColumns> GetConfigMetaData()
{
var requester = new ListRequester<OpenSQL, ConfigMetaDataColumns>(m_WITObject, "Result[0].RowCount", "Result[0].Row[{0}].");
return requester.Items;
}
public void InitRequest()
{
User user = (User)HttpContext.Current.User;
m_WITObject = user.NewService<OpenSQLAccessLayer>();
m_WITObject.SetInput("MultipleResultSets", 1);
m_WITObject.SetInput("ClientID", Utils.GetClientID());
m_WITObject.SetInput("GroupID", GroupID);
m_WITObject.SetInput("PageName", PageName);
m_WITObject.Retrieve();
}
}
}
This is the "GetClientID()" method:
public static int GetClientID()
{
User oUser = (User)HttpContext.Current.User;
int nClientID;
string sClientID = string.Empty;
if (String.IsNullOrEmpty(oUser.Session("clientid")))
{
Client oClient = new Client();
}
oUser = (User)HttpContext.Current.User;
sClientID = oUser.Session("clientid");
//If we couldn't retrieve it, throw exception
if ( string.IsNullOrEmpty(sClientID) || !int.TryParse(sClientID, out nClientID))
{
throw new Exception("No clientid found in user session, client not authenticated, please login from main page");
}
return nClientID;
}
I'm just looking for a way for me to pass in a hard-coded value for the ClientID, and use this to do some unit testing with the GetDataClass class.
Thanks.
You cannot mock a static method. You should use some means of dependency injection. Say you make your GetClientId method part of an interface called IUtils like so:
public interface IUtils
{
int GetClientId();
}
And you have your concrete class Utils implemented as above, but without the method being static (and implementing the interface of course).
You now inject an implementation of your interface into the GetDataClass
class by changing its constructor, like so:
public class GetDataClass
{
private readonly IUtils utils;
public GetDataClass(IUtils utils)
{
this.utils = utils;
}
//SNIP
}
In the InitRequest method you change the call Utils.GetClientID() to this.utils.GetClientId().
You are now ready to instantiate your GetDataClass class with a mock, like so:
var utilsMock = new Mock<IUtils>();
utilsMock.Setup(u => u.GetClientId()).Returns(42);
var getDataClass = new GetDataClass(utilsMock.Object);
getDataClass.InitRequest();
And that's it.