I am creating a CustomRepeat by extending CustomLoopTest. It never breaks in the IF condition.
Because break happens only for concrete class LoopTestStep, is it possible to modify LoopTestStep inside the IF condition by an interface? So we can implement that interface in our CustomLoopTestStep.
Another possiblity is to help to provide an alternative way.
public abstract class CustomLoopTestStep : CustomTestStep
{
protected CancellationTokenSource breakLoopToken { get; private set; }
[Browsable(false)]
protected CancellationToken BreakLoopRequested { get { return breakLoopToken.Token; } }
public CustomLoopTestStep()
{
breakLoopToken = new CancellationTokenSource();
}
public void BreakLoop()
{
breakLoopToken.Cancel();
}
/// <summary> Always call base.Run in LoopTestStep inheritors. </summary>
public override void Run()
{
breakLoopToken = new CancellationTokenSource();
}
}
At the moment (OpenTAP v9.4 and earlier), you need to inherit from LoopTestStep to interact with the If Verdict step. Otherwise if you prefer to achieve this by implementing an interface, you can submit a feature request here to add an interface in OpenTAP.
Related
When there are multiple named implementations for a given interface, how does the container (I am using Unity in a Prism application) know which one to inject unless I call the container.Resolve with the registered name? Here is a simple example:
public interface IDependencyClass
{
void DoSomething();
}
public class DependencyClassA : IDependencyClass
{
void DoSomething() { }
}
public class DependencyClassB : IDependencyClass
{
void DoSomething() { }
}
public interface IConsumer
{
void TakeUserSpecificAction();
}
public class Consumer : IConsumer
{
IDependencyClass dependencyInstance;
public Consumer(IDependencyClass _dependencyInstance)
{
dependencyInstance = _dependencyInstance;
}
public void TakeUserSpecificAction()
{
dependencyInstance.DoSomething();
}
}
public class MyBootStrapper : UnityBootstrapper
{
protected override void ConfigureContainer()
{
base.ConfigureContainer();
Container.RegisterType<IDependencyClass, DependencyClassA>( "InstanceA" );
Container.RegisterType<IDependencyClass, DependencyClassB>( "InstanceB" );
Container.RegisterType<IConsumer, Consumer>();
}
}
and here is my MainViewModel from my application. The "RaiseSomeCommand" command is not enabled until the user has logged in. When it is enabled, it can execute the ReaiseConsumerCommandRequest, which in turn calls the consumer. Here is my ViewModel.
public class MainWindowViewModel
{
private readonly IRegionManager regionManager;
private readonly ILoginService loginService;
private readonly IConsumer consumer;
public ICommand RaiseSomeCommand { get; set; }
public MainWindowViewModel( IRegionManager regMgr, ILoginService _loginService, IConsumer _consumer )
{
regionManager = regMgr;
loginService = _loginService;
consumer = _consumer;
NavigateCommand = new DelegateCommand<string>( Navigate );
LoginViewRequest = new InteractionRequest<INotification>();
RaiseSomeCommand = new DelegateCommand( RaiseConsumerCommandRequest );
}
private void RaiseConsumerCommandRequest()
{
consumer.TakeUserSpecificAction();
}
}
So, when I execute
consumer.TakeUserSpecificAction();
which DependencyClass instance am I using? DependencyClassA or DependencyClassB. Also, If I want to use specifically say DependencyClassB, What do I need to do to make it happen. I don't want to call
container.Reslove<IDependencyClass>("InstanceB")
in my ViewModel because I am then using the container as a service locator. I am also passing the container reference around.
I have seen in some code examples that the constructor parameter for the consumer class is decorated with a Dependency attribute like below.
public class Consumer
{
IDependencyClass dependencyInstance;
public Consumer([Dependency("InstanceB")]IDependencyClass _dependencyInstance)
{
dependencyInstance = _dependencyInstance;
}
}
But then, I am putting a hard constraint on the Consumer to use only the "InstanceB" implementation. Secondly, I am creating a dependency to Unity. Thirdly, now I have to clone the Consumer class to use "InstanceA" Implementation. That goes against the DRY principle.
I have heard that these conditions are application decisions and not an IoC related logic. I can agree with that argument. But then, where and how in the application would I resolve the right implementation without violating one rule or another?
I can't see how I can inject the right concrete instance unless I choose to use one of the above two options. Container.Resolve or Dependency attribute. Can anybody help please?
I'm trying to implement IoC in my windows form application. My choice fell on Simple Injector, because it's fast and lightweight. I also implement unit of work and repository pattern in my apps. Here is the structure:
DbContext:
public class MemberContext : DbContext
{
public MemberContext()
: base("Name=MemberContext")
{ }
public DbSet<Member> Members { get; set; }
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
base.OnModelCreating(modelBuilder);
modelBuilder.Conventions.Remove<PluralizingTableNameConvention>();\
}
}
Model:
public class Member
{
public int MemberID { get; set; }
public string Name { get; set; }
}
GenericRepository:
public abstract class GenericRepository<TEntity> : IGenericRepository<TEntity>
where TEntity : class
{
internal DbContext context;
internal DbSet<TEntity> dbSet;
public GenericRepository(DbContext context)
{
this.context = context;
this.dbSet = context.Set<TEntity>();
}
public virtual void Insert(TEntity entity)
{
dbSet.Add(entity);
}
}
MemberRepository:
public class MemberRepository : GenericRepository<Member>, IMemberRepository
{
public MemberRepository(DbContext context)
: base(context)
{ }
}
UnitOfWork:
public class UnitOfWork : IUnitOfWork
{
public DbContext context;
public UnitOfWork(DbContext context)
{
this.context = context;
}
public void SaveChanges()
{
context.SaveChanges();
}
private bool disposed = false;
protected virtual void Dispose(bool disposing)
{
if (!this.disposed)
{
if (disposing)
{
context.Dispose();
}
}
this.disposed = true;
}
public void Dispose()
{
Dispose(true);
GC.SuppressFinalize(this);
}
}
MemberService:
public class MemberService : IMemberService
{
private readonly IUnitOfWork unitOfWork;
private readonly IMemberRepository memberRepository;
public MemberService(IUnitOfWork unitOfWork, IMemberRepository memberRepository)
{
this.unitOfWork = unitOfWork;
this.memberRepository = memberRepository;
}
public void Save(Member member)
{
Save(new List<Member> { member });
}
public void Save(List<Member> members)
{
members.ForEach(m =>
{
if (m.MemberID == default(int))
{
memberRepository.Insert(m);
}
});
unitOfWork.SaveChanges();
}
}
In Member Form I only add a textbox to input member name and a button to save to database. This is the code in member form:
frmMember:
public partial class frmMember : Form
{
private readonly IMemberService memberService;
public frmMember(IMemberService memberService)
{
InitializeComponent();
this.memberService = memberService;
}
private void btnSave_Click(object sender, EventArgs e)
{
Member member = new Member();
member.Name = txtName.Text;
memberService.Save(member);
}
}
I implement the SimpleInjector (refer to http://simpleinjector.readthedocs.org/en/latest/windowsformsintegration.html) in Program.cs as seen in the code below:
static class Program
{
private static Container container;
[STAThread]
static void Main()
{
Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);
Bootstrap();
Application.Run(new frmMember((MemberService)container.GetInstance(typeof(IMemberService))));
}
private static void Bootstrap()
{
container = new Container();
container.RegisterSingle<IMemberRepository, MemberRepository>();
container.Register<IMemberService, MemberService>();
container.Register<DbContext, MemberContext>();
container.Register<IUnitOfWork, UnitOfWork>();
container.Verify();
}
}
When I run the program and add a member, it doesn't save to database. If I changed container.Register to container.RegisterSingle, it will save to database. From the documentation, RegisterSingle will make my class to be a Singleton. I can't using RegisterLifeTimeScope because it will generate an error
"The registered delegate for type IMemberService threw an exception. The IUnitOfWork is registered as 'Lifetime Scope' lifestyle, but the instance is requested outside the context of a Lifetime Scope"
1) How to use SimpleInjector in Windows Form with UnitOfWork & Repository pattern?
2) Do I implement the patterns correctly?
The problem you have is the difference in lifestyles between your service, repository, unitofwork and dbcontext.
Because the MemberRepository has a Singleton lifestyle, Simple Injector will create one instance which will be reused for the duration of the application, which could be days, even weeks or months with a WinForms application. The direct consequence from registering the MemberRepository as Singleton is that all dependencies of this class will become Singletons as well, no matter what lifestyle is used in the registration. This is a common problem called Captive Dependency.
As a side note: The diagnostic services of Simple Injector are able to spot this configuration mistake and will show/throw a Potential Lifestyle Mismatch warning.
So the MemberRepository is Singleton and has one and the same DbContext throughout the application lifetime. But the UnitOfWork, which has a dependency also on DbContext will receive a different instance of the DbContext, because the registration for DbContext is Transient. This context will, in your example, never save the newly created Member because this DbContext does not have any newly created Member, the member is created in a different DbContext.
When you change the registration of DbContext to RegisterSingleton it will start working, because now every service, class or whatever depending on DbContext will get the same instance.
But this is certainly not the solution because having one DbContext for the lifetime of the application will get you into trouble, as you probably already know. This is explained in great detail in this post.
The solution you need is using a Scoped instance of the DbContext, which you already tried. You are missing some information on how to use the lifetime scope feature of Simple Injector (and most of the other containers out there). When using a Scoped lifestyle there must be an active scope as the exception message clearly states. Starting a lifetime scope is pretty simple:
using (ThreadScopedLifestyle.BeginScope(container))
{
// all instances resolved within this scope
// with a ThreadScopedLifestyleLifestyle
// will be the same instance
}
You can read in detail here.
Changing the registrations to:
var container = new Container();
container.Options.DefaultScopedLifestyle = new ThreadScopedLifestyle();
container.Register<IMemberRepository, MemberRepository>(Lifestyle.Scoped);
container.Register<IMemberService, MemberService>(Lifestyle.Scoped);
container.Register<DbContext, MemberContext>(Lifestyle.Scoped);
container.Register<IUnitOfWork, UnitOfWork>(Lifestyle.Scoped);
and changing the code from btnSaveClick() to:
private void btnSave_Click(object sender, EventArgs e)
{
Member member = new Member();
member.Name = txtName.Text;
using (ThreadScopedLifestyle.BeginScope(container))
{
var memberService = container.GetInstance<IMemberService>();
memberService.Save(member);
}
}
is basically what you need.
But we have now introduced a new problem. We are now using the Service Locator anti pattern to get a Scoped instance of the IMemberService implementation. Therefore we need some infrastructural object which will handle this for us as a Cross-Cutting Concern in the application. A Decorator is a perfect way to implement this. See also here. This will look like:
public class ThreadScopedMemberServiceDecorator : IMemberService
{
private readonly Func<IMemberService> decorateeFactory;
private readonly Container container;
public ThreadScopedMemberServiceDecorator(Func<IMemberService> decorateeFactory,
Container container)
{
this.decorateeFactory = decorateeFactory;
this.container = container;
}
public void Save(List<Member> members)
{
using (ThreadScopedLifestyle.BeginScope(container))
{
IMemberService service = this.decorateeFactory.Invoke();
service.Save(members);
}
}
}
You now register this as a (Singleton) Decorator in the Simple Injector Container like this:
container.RegisterDecorator(
typeof(IMemberService),
typeof(ThreadScopedMemberServiceDecorator),
Lifestyle.Singleton);
The container will provide a class which depends on IMemberService with this ThreadScopedMemberServiceDecorator. In this the container will inject a Func<IMemberService> which, when invoked, will return an instance from the container using the configured lifestyle.
Adding this Decorator (and its registration) and changing the lifestyles will fix the issue from your example.
I expect however that your application will in the end have an IMemberService, IUserService, ICustomerService, etc... So you need a decorator for each and every IXXXService, not very DRY if you ask me. If all services will implement Save(List<T> items) you could consider creating an open generic interface:
public interface IService<T>
{
void Save(List<T> items);
}
public class MemberService : IService<Member>
{
// same code as before
}
You register all implementations in one line using Batch-Registration:
container.Register(typeof(IService<>),
new[] { Assembly.GetExecutingAssembly() },
Lifestyle.Scoped);
And you can wrap all these instances into a single open generic implementation of the above mentioned ThreadScopedServiceDecorator.
It would IMO even be better to use the command / handler pattern (you should really read the link!) for this type of work. In very short: In this pattern every use case is translated to a message object (a command) which is handled by a single command handler, which can be decorated by e.g. a SaveChangesCommandHandlerDecorator and a ThreadScopedCommandHandlerDecorator and LoggingDecorator and so on.
Your example would then look like:
public interface ICommandHandler<TCommand>
{
void Handle(TCommand command);
}
public class CreateMemberCommand
{
public string MemberName { get; set; }
}
With the following handlers:
public class CreateMemberCommandHandler : ICommandHandler<CreateMemberCommand>
{
//notice that the need for MemberRepository is zero IMO
private readonly IGenericRepository<Member> memberRepository;
public CreateMemberCommandHandler(IGenericRepository<Member> memberRepository)
{
this.memberRepository = memberRepository;
}
public void Handle(CreateMemberCommand command)
{
var member = new Member { Name = command.MemberName };
this.memberRepository.Insert(member);
}
}
public class SaveChangesCommandHandlerDecorator<TCommand>
: ICommandHandler<TCommand>
{
private ICommandHandler<TCommand> decoratee;
private DbContext db;
public SaveChangesCommandHandlerDecorator(
ICommandHandler<TCommand> decoratee, DbContext db)
{
this.decoratee = decoratee;
this.db = db;
}
public void Handle(TCommand command)
{
this.decoratee.Handle(command);
this.db.SaveChanges();
}
}
And the form can now depend on ICommandHandler<T>:
public partial class frmMember : Form
{
private readonly ICommandHandler<CreateMemberCommand> commandHandler;
public frmMember(ICommandHandler<CreateMemberCommand> commandHandler)
{
InitializeComponent();
this.commandHandler = commandHandler;
}
private void btnSave_Click(object sender, EventArgs e)
{
this.commandHandler.Handle(
new CreateMemberCommand { MemberName = txtName.Text });
}
}
This can all be registered as follows:
container.Register(typeof(IGenericRepository<>),
typeof(GenericRepository<>));
container.Register(typeof(ICommandHandler<>),
new[] { Assembly.GetExecutingAssembly() });
container.RegisterDecorator(typeof(ICommandHandler<>),
typeof(SaveChangesCommandHandlerDecorator<>));
container.RegisterDecorator(typeof(ICommandHandler<>),
typeof(ThreadScopedCommandHandlerDecorator<>),
Lifestyle.Singleton);
This design will remove the need for UnitOfWork and a (specific) service completely.
Within MVC Web Application DbContext binding work properly with InRequestScope()
kernel.Bind<DbContext>().ToSelf().InRequestScope();
kernel.Bind<IUnitOfWork<DbContext>>().To<UnitOfWork<DbContext>>();
But from a Task Scheduler call DbContext in InRequestScope() unable to update Db Table (without any error), until I change Binding to InSingletonScope() OR InThreadScope()
Question: So is their any way change scope to InSingletonScope() / InThreadScope() for a Task Scheduler Call. ?
// For Task Scheduler Call, I tried bellow bind, but not working properly
kernel.Bind<DbContext>().ToSelf()
.When(request => request.Target.Type.Namespace.StartsWith("NameSpace.ClassName"))
.InSingletonScope();
** And probably I miss some thing. Need help.
Code Snippet Updated
#region Commented Code
public EmailTask() : this
( DependencyResolver.Current.GetService<IMessageManager>(),
, DependencyResolver.Current.GetService<IUnitOfWork<DbContext>>()) { }
#endregion
public EmailTask(IMessageManager messageManager, IUnitOfWork<DbContext> unitOfWork)
{
this._messageManager = messageManager;
this._unitOfWork = unitOfWork;
ProcessEmail();
}
public class NonRequestScopedParameter : IParameter { ... }
public void ProcessEmail()
{
var temp = SomeRepository.GetAll();
SendEmail(temp);
temp.Date = DateTime.Now;
SomeRepository.Update(temp);
unitOfWork.Commit();
}
public class ExecuteEmailTask : ITask
{
private readonly IResolutionRoot _resolutionRoot;
private int _maxTries = 5;
public ExecuteEmailTask(IResolutionRoot resolutionRoot)
{
_resolutionRoot = resolutionRoot;
}
public void Execute(XmlNode node)
{
XmlAttribute attribute1 = node.Attributes["maxTries"];
if (attribute1 != null && !String.IsNullOrEmpty(attribute1.Value))
{
this._maxTries = int.Parse(attribute1.Value);
}
/// send email messages
var task = _resolutionRoot.Get<EmailTask>(new NonRequestScopedParameter());
}
}
In Web.Config
<ScheduleTasks>
<Thread seconds="60">
<task name="ExecuteEmailTask" type="namespace.ExecuteEmailTask, AssemblyName" enabled="true" stopOnError="false" maxTries="5"/>
</Thread>
</ScheduleTasks>
In Global.asax
protected void Application_Start()
{
/* intialize Task */
TaskConfig.Init();
TaskManager.Instance.Initialize(TaskConfig.ScheduleTasks);
TaskManager.Instance.Start();
}
Ninject Bind Syntax
kernel.Bind<DbContext>().ToSelf().InRequestScope(); // Default bind
kernel.Bind<DbContext>().ToSelf()
.When(x => x.Parameters.OfType<NonRequestScopedParameter>().Any())
.InCallScope(); // For Scheduler
Note: EmailTask class also have SomeReposity as a Constructor Argument.
Queries:-
But what is the bind syntax to resolve TaskScheduler(IResolutionRoot resolutionRoot) ?
What is the configuration code to run TaskScheduler ?
As say to put IFakeDbContext directly into constructor, can this work with IUnitOfWork<FakeDbContext> ?
Problem
Task unable to call with Overloaded Constructor , it is only able to call TaskScheduler default Constructor.
Question 4: Can any way to invoke TaskScheduler(IResolutionRoot resolutionRoot) from TaskScheduler default constructor ?
Sample Code Snippet to create Task & run using System.Threading.Timer
private ITask createTask()
{
if (this.Enabled && (this._task == null))
{
if (this._taskType != null)
{
this._task = Activator.CreateInstance(this._taskType) as ITask;
}
this._enabled = this._task != null;
}
return this._task;
}
Question 5: Can I resolve TaskScheduler(IResolutionRoot resolutionRoot) here ?
Solved
public ExecuteEmailTask() :
this(DependencyResolver.Current.GetService<IResolutionRoot>())
OR
public ExecuteEmailTask() : this(new Bootstrapper().Kernel) { }
public ExecuteEmailTask(IResolutionRoot resolutionRoot)
{
_resolutionRoot = resolutionRoot;
}
First of, you should note that InSingletonScope() is usually a bad idea for DbContext's/Sessions. What happens if some other service changes data in the meantime? I would recommend investigating what effects this has.
For the scenario you first described, a correctly formulated .When(...) should work.
As an alternative to the .When(...) binding you could also use a .Named("FooBar") binding.
The constructor of the scheduled task would then need to look like:
ctor(Named["FooBar"] DbContext dbContext);
However, note, that this only (easily) works in case you need to inject the DbContext into a single constructor. If the task features dependencies and these need the same DbContext instance, too, it gets a bit tricker.
Since you updated your answer and say that this is the case, i would recommend an entirely different approach: Using a request parameter as basis for the When(...) condition combined with InCallScope binding. See below for an example.
Brace yourself, this is ab it of code :) The implementation requires the ninject.extensions.NamedScope extension (nuget).
I've also used xUnit and FluentAssertions nuget packages to execute the tests.
public class Test
{
// the two implementations are just for demonstration and easy verification purposes. You will only use one DbContext type.
public interface IFakeDbContext { }
public class RequestScopeDbContext : IFakeDbContext { }
public class CallScopeDbContext : IFakeDbContext { }
public class SomeTask
{
public IFakeDbContext FakeDbContext { get; set; }
public Dependency1 Dependency1 { get; set; }
public Dependency2 Dependency2 { get; set; }
public SomeTask(IFakeDbContext fakeDbContext, Dependency1 dependency1, Dependency2 dependency2)
{
FakeDbContext = fakeDbContext;
Dependency1 = dependency1;
Dependency2 = dependency2;
}
}
public class Dependency1
{
public IFakeDbContext FakeDbContext { get; set; }
public Dependency1(IFakeDbContext fakeDbContext)
{
FakeDbContext = fakeDbContext;
}
}
public class Dependency2
{
public IFakeDbContext FakeDbContext { get; set; }
public Dependency2(IFakeDbContext fakeDbContext)
{
FakeDbContext = fakeDbContext;
}
}
public class TaskScheduler
{
private readonly IResolutionRoot _resolutionRoot;
public TaskScheduler(IResolutionRoot resolutionRoot)
{
_resolutionRoot = resolutionRoot;
}
public SomeTask CreateScheduledTaskNow()
{
return _resolutionRoot.Get<SomeTask>(new NonRequestScopedParameter());
}
}
public class NonRequestScopedParameter : Ninject.Parameters.IParameter
{
public bool Equals(IParameter other)
{
if (other == null)
{
return false;
}
return other is NonRequestScopedParameter;
}
public object GetValue(IContext context, ITarget target)
{
throw new NotSupportedException("this parameter does not provide a value");
}
public string Name
{
get { return typeof(NonRequestScopedParameter).Name; }
}
// this is very important
public bool ShouldInherit
{
get { return true; }
}
}
[Fact]
public void FactMethodName()
{
var kernel = new StandardKernel();
// this is the default binding
kernel.Bind<IFakeDbContext>().To<RequestScopeDbContext>();
// this binding is _only_ used when the request contains a NonRequestScopedParameter
// in call scope means, that all objects built in the a single request get the same instance
kernel.Bind<IFakeDbContext>().To<CallScopeDbContext>()
.When(x => x.Parameters.OfType<NonRequestScopedParameter>().Any())
.InCallScope();
// let's try it out!
var task = kernel.Get<SomeTask>(new NonRequestScopedParameter());
// verify that the correct binding was used
task.FakeDbContext.Should().BeOfType<CallScopeDbContext>();
// verify that all children of the task get injected the same task instance
task.FakeDbContext.Should()
.Be(task.Dependency1.FakeDbContext)
.And.Be(task.Dependency2.FakeDbContext);
}
}
Since, as you say, the task scheduler does not make use of the IoC to create the task, it only supports a parameterless constructor. In that case you can make use DependencyResolver.Current (however, note that i'm in no way an expert on asp.net /MVC so i'm not making any claims that this is thread safe or working 100% reliably):
public class TaskExecutor : ITask
{
public TaskExecutor()
: this(DependencyResolver.Current.GetService<IResolutionRoot>())
{}
internal TaskExecutor(IResolutionRoot resolutionRoot)
{
this.resolutionRoot = resolutionRoot;
}
public void Execute()
{
IFooTask actualTask = this.resolution.Get<IFooTask>(new NonRequestScopedParameter());
actualTask.Execute();
}
}
I'm having serious issues in how to deploy a WCF client in a MVC site which is easily testable. I'm struggling to set up a mock of the service without actually accessing a endpoint.
Example Controller of site under test
public class ProfileController : ControllerExtended
{
public ProfileController(IUserService membershipService, IDropDownService dropdownService, ISiteService siteService)
{
WCFService.Instance.Client = siteService; //Should maybe be a serpate service.
_membershipService = membershipService;
_dropDownService = dropdownService;
_siteService = siteService;
}
public ActionResult Index()
{
UserComp profile = _siteService.ProfileGet(_sharedContext.CurrentUser.id);
return View(new ProfileViewModel { Profile = profile });
}
}
WCF Singleton (I think my implementation of WCF is my issue, should it be in a interface?)
public sealed class WCFService
{
public SiteServiceI Client { get; set; }
#region Singleton
static readonly WCFService query = new WCFService();
static WCFService()
{
}
WCFService()
{
}
public static WCFService Instance
{
get { return query; }
}
#endregion
}
UnitTest
[TestFixture]
public class UnitTest1
{
private Mock<SiteService> mockSiteService;
private Mock<IUserService> mockMembershipService;
private Mock<IDropDownService> mockDropDown;
private Mock<SiteServiceIClient> mockServiceClient; //new Mock<SiteServiceIClient>();
//private Mock<WebService> mockWebService;
[SetUp]
public void SetUp()
{
mockSiteService = new Mock<ISiteService>();
mockMembershipService = new Mock<IUserService>();
mockDropDown = new Mock<IDropDownService>();
mockServiceClient = new Mock<SiteServiceIClient>();
mockWebService = new Mock<WebService>(mockServiceClient);
}
[Test]
public void CheckHomeIndex_Controller()
{
var controller = new HomeController(mockMembershipService.Object, mockDropDown.Object, mockPTSearch.Object, mockServiceClient.Object); // mockServiceClient times out.
Assert.AreEqual("this", "this");
}
}
I assume the errors are occurring because the singleton sets the service up as soon as it is initialised. I've tried to implement a separate service purely for called to WCF but not had success in implementing it in a testable manner. Not too sure if this is to vague but I've read a lot on it and not an closer.
The singleton is definitely your problem - testing with singletons is entering a world of pain. You should implement a facade pattern to make this testing friendly. Something like this:
public interface IServiceFacade
{
Profile ProfileGet(int id);
}
public class ServiceFacade : IServiceFacade
{
private WCFService _theRealService = new WCFService();
public Profile ProfileGet(int id)
{
return _theRealService.ProfileGet(id);
}
}
public class Some_Tests()
{
public void Test_Stuff_Whatever()
{
Mock<IServiceFacade> _facade = new Mock<IServiceFacade>();
_facade.SetUp(Whatever.....);
}
}
Your problem is that your service is singleton. The problem of singleton pattern is that it is not testable. You should use Dependency injection to get service.
I've tried to build some base project with above technologies. I wanted maximum flexibility and testability so I tried to use patterns along the way to make this as a base for future projects. However, it seem
something is wrong or whatever and I really need help here. So i have two questions :
Is there anything wrong with my current code? I've applied patterns correctly? Any suggestions or recommendation that would lead me in the right direction?
Why do this code actually connect to the database, create it, but doesn't support insert even if I perform the corrects operation? (Look at the end of the post for details about this error) FIXED
I believe this could also help others since I haven't found enough information in order to make something up correctly. I am pretty sure lots of people try to do it the right way and are not sure like me if what I am doing is right.
I have two entities: Comment and Review
COMMENT
public class Comment
{
[Key]
public virtual int Id { get; set; }
public virtual string Name { get; set; }
public virtual string Author { get; set; }
public virtual string Body { get; set; }
}
REVIEW
public class Review
{
[Key]
public virtual int Id { get; set; }
public virtual string Name { get; set; }
public virtual string Author { get; set; }
public virtual string Body { get; set; }
public virtual bool Visible { get; set; }
public IEnumerable<Comment> Comments { get; set; }
}
I built up a base repository for each of them this way :
GENERIC REPOSITORY
public abstract class EFRepositoryBase<T> : IRepository<T> where T : class
{
private Database _database;
private readonly IDbSet<T> _dbset;
protected IDatabaseFactory DatabaseFactory { get; private set; }
protected Database Database { get { return _database ?? (_database = DatabaseFactory.Get()); } }
public EFRepositoryBase(IDatabaseFactory databaseFactory)
{
DatabaseFactory = databaseFactory;
_dbset = Database.Set<T>();
}
public virtual void Add(T entity)
{
_dbset.Add(entity);
}
public virtual void Delete(T entity)
{
_dbset.Remove(entity);
}
public virtual T GetById(long id)
{
return _dbset.Find(id);
}
public virtual IEnumerable<T> All()
{
return _dbset.ToList();
}
}
For specific operations, I use an interface:
public interface IReviewRepository : IRepository<Review> {
// Add specific review operations
IEnumerable<Review> FindByAuthor(string author);
}
So I am getting the generics operations from the abstract class plus the specific operations:
public class EFReviewRepository : EFRepositoryBase<Review>, IReviewRepository
{
public EFReviewRepository(IDatabaseFactory databaseFactory)
: base(databaseFactory)
{ }
public IEnumerable<Review> FindByAuthor(string author)
{
return base.Database.Reviews.Where(r => r.Author.StartsWith(author))
.AsEnumerable<Review>();
}
}
As you figured out, I also use a database factory will produce the database context :
DATABASE FACTORY
public class DatabaseFactory : Disposable, IDatabaseFactory
{
private Database _database;
public Database Get()
{
return _database ?? (_database = new Database(#"AppDb"));
}
protected override void DisposeCore()
{
if (_database != null)
_database.Dispose();
}
}
DISPOSABLE (Some extensions methods...)
public class Disposable : IDisposable
{
private bool isDisposed;
~Disposable()
{
Dispose(false);
}
public void Dispose()
{
Dispose(true);
GC.SuppressFinalize(this);
}
private void Dispose(bool disposing)
{
if (!isDisposed && disposing)
{
DisposeCore();
}
isDisposed = true;
}
protected virtual void DisposeCore()
{
}
}
DATABASE
public class Database : DbContext
{
private IDbSet<Review> _reviews;
public IDbSet<Review> Reviews
{
get { return _reviews ?? (_reviews = DbSet<Review>()); }
}
public virtual IDbSet<T> DbSet<T>() where T : class
{
return Set<T>();
}
public Database(string connectionString)
: base(connectionString)
{
//_reviews = Reviews;
}
public virtual void Commit()
{
base.SaveChanges();
}
/*
protected override void OnModelCreating(ModelBuilder modelBuilder)
{
// TODO: Use Fluent API Here
}
*/
}
And to finish, I have my unit of work....
UNIT OF WORK
public class UnitOfWork : IUnitOfWork
{
private readonly IDatabaseFactory _databaseFactory;
private Database _database;
public UnitOfWork(IDatabaseFactory databaseFactory)
{
_databaseFactory = databaseFactory;
}
protected Database Database
{
get { return _database ?? (_database = _databaseFactory.Get()); }
}
public void Commit()
{
Database.Commit();
}
}
I also bound using Ninject the interfaces:
NINJECT CONTROLLER FACTORY
public class NinjectControllerFactory : DefaultControllerFactory
{
// A Ninject "Kernel" is the thing that can supply object instances
private IKernel kernel = new StandardKernel(new ReviewsDemoServices());
// ASP.NET MVC calls this to get the controller for each request
protected override IController GetControllerInstance(RequestContext requestContext, Type controllerType)
{
if (controllerType == null)
return null;
return (IController)kernel.Get(controllerType);
}
private class ReviewsDemoServices : NinjectModule
{
public override void Load()
{
// Bindings...
Bind<IReviewRepository>().To<EFReviewRepository>();
Bind<IUnitOfWork>().To<UnitOfWork>();
Bind<IDatabaseFactory>().To<DatabaseFactory>();
Bind<IDisposable>().To<Disposable>();
}
}
}
However, when I call in the constructor (the default action) ...
public class ReviewController : Controller
{
private readonly IReviewRepository _reviewRepository;
private readonly IUnitOfWork _unitOfWork;
public ReviewController(IReviewRepository postRepository, IUnitOfWork unitOfWork)
{
_reviewRepository = postRepository;
_unitOfWork = unitOfWork;
}
public ActionResult Index()
{
Review r = new Review { Id = 1, Name = "Test", Visible = true, Author = "a", Body = "b" };
_reviewRepository.Add(r);
_unitOfWork.Commit();
return View(_reviewRepository.All());
}
}
This seem to create the database but doesnt't insert anything in the database in EF4. It seem that I may figured out the problem.. while looking at the database object.. the connection state is closed and server version throw an exception of this kind :
ServerVersion = '(((System.Data.Entity.DbContext (_database)).Database.Connection).ServerVersion' threw an exception of type 'System.InvalidOperationException'
I am doing the right things? Is there anything wrong in what I've built ?
Also if you have recommandation about the code I posted, I would be glad. I am just trying to the learn the right way for building any kind of application in MVC 3. I want a good a start.
I use :
Entity Framework 4 with Code-First
ASP.NET MVC 3
Ninject as DI Container
SQL Server Express (not R2)
Visual Studio 2010 Web Express
Eww. This one was sneaky. Actually i don't know ninject much so i couldnt figure it out right away.
I found the solution for the SECOND question which was related to the error by finding that ninject actually shoot two instance of the DatabaseFactory, one for the repository and one for the unit of work. Actually, the error was not the problem. It was an internal error in the object database but its normal i think since im using Entity Framework.
The real problem was that Ninject was binding two different instance of IDatabaseFactory which lead to 2 connection open.
The review was added to the first set in _reviewRepostory which was using the first instance of the Database.
When calling commit on the unit of work.. it saved nothing due to the fact that the review wasnt on this database instance. In fact, the unit of work called the databasefactory which lead to creating a new instance since ninject sent a new instance of it.
To fix it simply use :
Bind<IDatabaseFactory>().To<DatabaseFactory>().InSingletonScope();
instead of
Bind<IDatabaseFactory>().To<DatabaseFactory>();
And now all the system work correctly!
Now, would love some answers regarding the first question which was if there anything wrong with my current code ? Ive applied patterns correctly ? Any suggestions or recommendation that would lead me in the right direction ?
One small observation: by having your EFRepositoryBase and IReviewRepository have methods that return an IEnumerable<> instead of an IQueryable<>, you prevent subsequent methods from adding filter expressions/constraints or projections or so on to the query. Instead, by using IEnumerable<>, you will do any subsequent filtering (e.g. using LINQ extension methods) on the full result set, rather than allowing those operations to affect and simplify the SQL statement that gets run against the datastore.
In other words, you are doing further filtering at the webserver level, not at the database level where it really belongs if possible.
Then again, this may be intentional - sometimes using IEnumerable<> is valid if you do want to prevent callers of your function from modifying the SQL that is generated, etc.