ServiceStack.Funq.Quartz cannot instantiating type? - servicestack

ServiceStack.Funq.Quartz Sample Code is
public class MyServices : Service
{
public object Any(Hello request)
{
return new HelloResponse { Result = "Hello, {0}!".Fmt(request.Name) };
}
}
public class HelloJob : IJob
{
private MyServices MyServices { get; set; }
public HelloJob(MyServices myServices)
{
MyServices = myServices;
}
public void Execute(IJobExecutionContext context)
{
var response = MyServices.Any(new ServiceModel.Hello
{
Name = "CodeRevver"
});
response.PrintDump();
}
}
The above is works fine. if I in the MyServices Class, removed the Any function, and comment the Execute inner code.
public class MyServices : Service
{
}
the quartz.net will get the error:
[Quartz.Core.ErrorLogger】 An error occurred instantiating job to be executed. job= 'JobGroup1.GetUserJob111' Problem instantiating type 'ServiceStackWithQuartz.HelloJob'
why the class must have public object Any(Hello request) function ?

Thanks for using the package – I had no idea that other people would find it useful.
So If I understand correctly, in your situation you have:
public class MyServices : Service
{
}
And you’re trying to resolve this Service via constructor injection, which is effectively doing a:
container.Resolve<MyServices>();
This will fail because of the way the ServiceStack Funq IoC works. You can’t resolve a ServiceStack Service that has nothing in it (you'd probably never want to either) – It has to at least have one service implementation, It doesn’t matter what the implementation is.
Also, if you want to improve ServiceStack.Funq.Quartz, feel free to contribute to the code base.
Edit: It's probably worth mentioning that you can inject a "Non-Service" class with your logic in it if you want. You can resolve other classes that aren't based off of ServiceStack.Service even if there's nothing in them.
Edit 2: Responding to your "Service wont dispose" problem. This is the same across ServiceStack and has nothing to do with your Quartz Job. If you call a:
container.Resolve<MyServices>().Any(new new ServiceModel.Hello { });
from AppHost for example, your service wont dispose by itself. If you want it to dispose you can wrap it in a using statement. e.g.
using (var service = MyServices)
{
var response = MyServices.Any(new ServiceModel.Hello { });
}
The using will ensure that your service will be disposed afterwards.
Alternatively you can add the interface "IDispose" on to your Quartz Job and implement a Dispose() method that will do a:
MyServices.Dispose();
This will be called after a job has executed.

Related

Why does ServiceStack burden the DTOs with routing concerns?

I'm learning ServiceStack, and from reading this page, a couple of things aren't clear to me.
So, considering this DTO pair:
[Route("/hello")]
[Route("/hello/{Name}")]
public class Hello : IReturn<HelloResponse>
{
public string Name { get; set; }
}
public class HelloResponse
{
public string Result { get; set; }
}
And this service:
public class MyService : Service
{
public object Any(Hello request)
{
return new HelloResponse { Result = $"Hello, {request.Name}!" };
}
}
Why is it the responsibility of Hello to specify the return-type using the marker interface IReturn<HelloResponse>?
It seems like this could be inferred from the return-type of MyService - except that it's conventional to use a return-type of object, which also requires type-casts in tests and client-code. Why?
And why are the Route attributes applied to the model Hello, rather than to the service MyService, where the request is actually handled?
It seems like both of these facts are more relevant to the service than to the model.
For one, a person reading the service declaration would more readily find the information pertaining to the service, instead of having to find it in the model.
For another, accepted HTTP methods are implicitly declared by the service via method-naming conventions - so it seems like the facts about service routing/dispatch are sort of scattered between two layers.
From that point of view, I was probably expecting something more along the lines of this:
// NON-VALID EXAMPLE
public class Hello
{
public string Name { get; set; }
}
public class HelloResponse
{
public string Result { get; set; }
}
public class MyService : Service
{
[Route("/hello")]
[Route("/hello/{Name}")]
public HelloResponse Any(Hello request)
{
return new HelloResponse { Result = $"Hello, {request.Name}!" };
}
}
What is the reason or the design thinking behind the conventions?
(Please don't take this as merely an attempt at critique - there's a lot of things I enjoy about this framework, and I am genuinely trying to understand the thinking behind these conventions.)
Why does ServiceStack burden the DTOs with routing concerns?
Note no routing concern burden is required at all in ServiceStack and all user-defined Routes are optional where all clients are able to call Services utilizing their automatic pre-defined routes.
Why is it the responsibility of Hello to specify the return-type using the marker interface IReturn?
It provides better typed access for client libraries like the generic C#/.NET Service Clients who are able to re-use the existing SericeModel DTOs to enable its optimal typed API without any code-gen, e.g:
var client = new JsonServiceClient(baseUrl);
var response = client.Get(new Hello { Name = "World" });
Or if you're not sharing DTOs it's also useful for Add ServiceStack Reference generated clients as well.
The return type on your Service implementation is meaningless in ServiceStack, i.e. has no behavioral difference, and would prevent the same Service implementation from returning the same Response DTO, or decorated with a custom HTTP Response, e.g:
public object Any(Hello request)
{
return new HelloResponse { Result = $"Hello, {request.Name}!" };
//...
return new HttpResult(new HelloResponse { Result = $"Hello, {request.Name}!" }) {
//... custom
};
}
both return types adhere to the API's IReturn<HelloResponse> contract
It's only useful for calling inter-process Services using the older ResolveService method, but for inter-prcess requests it's recommended to use the Service Gateway instead which also utilizes the type IReturn<T> interface markers for its Typed APIs.
The routes are not an implementation detail, they're apart of your public Service Contract and should be annotated on your DTOs which are used to define your Service Contract.
[Route("/hello")]
[Route("/hello/{Name}")]
public class Hello : IReturn<HelloResponse>
{
public string Name { get; set; }
}
public class HelloResponse
{
public string Result { get; set; }
}
Where they're used by the .NET ServiceStack Clients to send Service Client Requests.
var response = client.Get(new Hello { Name = "World" });
For another, accepted HTTP methods are implicitly declared by the service via method-naming conventions - so it seems like the facts about service routing/dispatch are sort of scattered between two layers.
Please see docs on Routing, the Route definition defines which methods the specific route is active on whilst the most appropriate Service implementation is invoked depending on the Request, e.g:
public object GetJson(Customers request) => ... // ONLY GET JSON Requests
public object Get(Customers request) => ... // All other GET Requests
public object Post(Customers request) => ... // ONLY POST Requests
public object Any(Customers request) => ... // ALL other Requests
What is the reason or the design thinking behind the conventions?
A lot of these issues is trying to blur the explicit typed Service Contract of your APIs and its concrete implementation, in ServiceStack these are distinct explicit concepts where all the information about your public Service Contract should be maintained in your implementation-free ServiceModel project.
Please read the Background Concepts docs to familiarize yourself with ServiceStack's purpose and goals.

ServiceStack: Accessing the IRequest in the Service returns null

I am using Servicestack. I have a base class for my Services, like so:
public abstract class ServiceHandlerBase : Service
and then some methods and properties in there of interest. I already have several methods that accesses the IRequest object, like:
protected AlfaOnline GetContactItem()
{
string deviceUUID = Request.Headers.Get(Constants.DEVICE_UUID); // <-- calling this method from constructor will give NullRef on Request here
string authToken = Request.Headers.Get(Constants.AUTH_TOKEN);
// do stuff
return existingContactItem;
}
which works well inside my service implementations, no problems there.
Now, I wanted to use this exact same method directly from the base class, calling it in the constructor:
public ServiceHandlerBase()
{
AlfaOnline ao = GetContactItem();
}
but I then get a NullReferenceException on the Request object as noted above.
When is the Request object ready to access and use? Because it's not null inside the service implementations.
You can't access any dependencies like IRequest in the constructor before they've been injected, they're only accessible after the Service class has been initialized like when your Service method is called.
You can use a Custom Service Runner to execute custom logic before any Service is Executed, e.g:
public class MyServiceRunner<T> : ServiceRunner<T>
{
public override void OnBeforeExecute(IRequest req, TRequest requestDto) {
// Called just before any Action is executed
}
}
And register it with ServiceStack in your AppHost with:
public override IServiceRunner<TRequest> CreateServiceRunner<TRequest>(ActionContext ctx)
{
return new MyServiceRunner<TRequest>(this, ctx);
}
But if you just want to run some logic for a Service class you can now override OnBeforeExecute() in your base class, e.g:
public abstract class ServiceHandlerBase : Service
{
public override void OnBeforeExecute(object requestDto)
{
AlfaOnline ao = GetContactItem();
}
}
See ServiceFilterTests.cs for a working example.
If you're implementing IService instead of inheriting the Service base class you can implement IServiceBeforeFilter instead.
The new Service Filters is available from v5.4.1 that's now available on MyGet.

Using StructureMap[4.7.0] Setter Injection in my MVC5 Controller

I am trying to inject the IApplicationConfigurationSection implementation into this MVC5 Controller, so that I can have access to some of the information (various strings) from my web.config custom section in all of my views:
public class BaseController : Controller
{
public IApplicationConfigurationSection AppConfig { get; set; }
public BaseController()
{
ViewBag.AppConfig = AppConfig; // AppConfig is always null
}
}
I want to use setter injection so I don't have to clutter up my derived Controller constructors with parameters that they don't really care about.
Note: If there is a better way to inject base class dependencies, please let me know. I admit I may not be on the right track here.
In my Global.asax I load my StructureMap configurations:
private static IContainer _container;
protected void Application_Start()
{
_container = new Container();
StructureMapConfig.Configure(_container, () => Container ?? _container);
// redacted other registrations
}
My StructureMapConfig class loads my registries:
public class StructureMapConfig
{
public static void Configure(IContainer container, Func<IContainer> func)
{
DependencyResolver.SetResolver(new StructureMapDependencyResolver(func));
container.Configure(cfg =>
{
cfg.AddRegistries(new Registry[]
{
new MvcRegistry(),
// other registries redacted
});
});
}
}
My MvcRegistry provides the mapping for StructureMap:
public class MvcRegistry : Registry
{
public MvcRegistry()
{
For<BundleCollection>().Use(BundleTable.Bundles);
For<RouteCollection>().Use(RouteTable.Routes);
For<IPrincipal>().Use(() => HttpContext.Current.User);
For<IIdentity>().Use(() => HttpContext.Current.User.Identity);
For<ICurrentUser>().Use<CurrentUser>();
For<HttpSessionStateBase>()
.Use(() => new HttpSessionStateWrapper(HttpContext.Current.Session));
For<HttpContextBase>()
.Use(() => new HttpContextWrapper(HttpContext.Current));
For<HttpServerUtilityBase>()
.Use(() => new HttpServerUtilityWrapper(HttpContext.Current.Server));
For<IApplicationConfigurationSection>()
.Use(GetConfig());
Policies.SetAllProperties(p => p.OfType<IApplicationConfigurationSection>());
}
private IApplicationConfigurationSection GetConfig()
{
var config = ConfigurationManager.GetSection("application") as ApplicationConfigurationSection;
return config; // this always returns a valid instance
}
}
I have also "thrown my hands up" and tried using the [SetterProperty] attribute on the BaseController - that technique failed as well.
Despite my best efforts to find a solution, the AppConfig property in my controller's constructor is always null. I thought that
`Policies.SetAllProperties(p => p.OfType<IApplicationConfigurationSection>());`
would do the trick, but it didn't.
I have found that if I discard setter injection and go with constructor injection, it works as advertised. I'd still like to know where I'm going wrong, but I'd like to stress that I'm not a StructureMap guru - there may be a better way to avoid having to constructor-inject my base class dependencies. If you know how I should be doing this but am not, please share.
While constructor injection in this scenario appears to be the better solution to the stated problem as it follows The Explicit Dependencies Principle
Methods and classes should explicitly require (typically through method parameters or constructor parameters) any collaborating objects they need in order to function correctly.
The mention of only needing to access the AppConfig in your views leads me to think that this is more of an XY problem and a cross cutting concern.
It appears that the controllers themselves have no need to use the dependency so stands to reason that there is no need to be injecting them into the controller explicitly just so that the dependency is available to the View.
Consider using an action filter that can resolve the dependency and make it available to the View via the same ViewBag as the request goes through the pipeline.
public class AccessesAppConfigAttribute : ActionFilterAttribute {
public override void OnActionExecuting(ActionExecutingContext filterContext) {
var resolver = DependencyResolver.Current;
var appConfig = (IApplicationConfigurationSection)resolver.GetService(typeof(IApplicationConfigurationSection));
filterContext.Controller.ViewBag.AppConfig = appConfig;
}
}
This now makes the required information available to the views with out tight coupling of the controllers that may have a use for it. Removing the need to inject the dependency into derived classes.
Either via adorning Controller/Action with the filter attribute
[AccessesAppConfig] //available to all its actions
public class HomeController : Controller {
//[AccessesAppConfig] //Use directly if want to isolate to single action/view
public ActionResult Index() {
//...
return View();
}
}
or globally for all requests.
public class FilterConfig {
public static void RegisterGlobalFilters(GlobalFilterCollection filters) {
filters.Add(new AccessesAppConfigAttribute());
}
}
At this point it really does not matter which IoC container is used. Once the dependency resolver has been configured, Views should have access to the required information in the ViewBag

Approach on mocking ServiceStack service being called by another ServiceStack service

Let's say we have a situation where a service would call other services in ServiceStack.
From reading around, this is how one would call another service:
public class CompanyService : Service
{
public SetupCompanyResponse Any(SetupCompany request)
{
var employeeService = base.ResolveService<EmployeeService>();
// Do something with employeeService
var response = employeeService.Any(new SetupEmployees());
return new SetupCompanyResponse { NumOfEmployeesCreated = response.Count };
}
}
Question: How do I mock EmployeeService if I'm unit-testing CompanyService?
Easiest way I could think of is to generate an IEmployeeService interface so that it's easily mockable. However I'm not sure if base.ResolveService<T> will be able to properly resolve and auto-wire a ServiceStack service, given its interface instead, like so:
var employeeService = base.ResolveService<IEmployeeService>();
Especially when we are registering services this way (which I assume is configuring the object resolution based on concrete class, and not the interface e.g IEmployeeService)
public HelloAppHost() : base("Hello Web Services", typeof(HelloService).Assembly) { }
Update:
Apparently I'm able to somewhat achieve this simply by:
1) Registering the service interface with its implementation
public static void SetupServices(Container container)
{
container.RegisterAs<EmployeeService, IEmployeeService>();
}
2) Using the same exact code to resolve, except now I pass in the interface. The service is successfully resolved.
var employeeService = base.ResolveService<IEmployeeService>();
3) All I need to do now is to override the resolver, and the service dependency should be totally mockable.
Question: Is this also a valid approach? Why or why not?
ServiceStack's Service class resolves all its dependencies from an IResolver, defined by:
public interface IResolver
{
T TryResolve<T>();
}
This can be injected in ServiceStack's Service class in an number of ways as seen by the implementation:
public class Service : IService, IServiceBase, IDisposable
{
public static IResolver GlobalResolver { get; set; }
private IResolver resolver;
public virtual IResolver GetResolver()
{
return resolver ?? GlobalResolver;
}
public virtual Service SetResolver(IResolver resolver)
{
this.resolver = resolver;
return this;
}
public virtual T TryResolve<T>()
{
return this.GetResolver() == null
? default(T)
: this.GetResolver().TryResolve<T>();
}
...
}
Which you can use to control how Services resolve dependencies.
An easy way to unit test Services is to use a BasicAppHost as seen on the Testing wiki, i.e:
appHost = new BasicAppHost().Init();
var container = appHost.Container;
container.Register<IDbConnectionFactory>(
new OrmLiteConnectionFactory(":memory:", SqliteDialect.Provider));
container.RegisterAutoWired<CompanyService>();
container.RegisterAutoWiredAs<StubEmployeeService, EmployeeService>();
Where StubEmployeeService is your stub implementation of EmployeeService, e.g:
public class StubEmployeeService : EmployeeService
{
public SetupEmployeesResponse Any(SetupEmployees request)
{
return new SetupEmployeesResponse { ... };
}
}
You can also register Services using any of the registration methods ServiceStack's IOC Supports if you prefer to use your own mocking library.

How should container behave when it is disposed?

Should it throw an exception, pass resolution to its parent or something else?
My favorite container Autofac raises an exception - which is the only thing I don't like about it.
I think that it should pass resolution to its parent which should resolve my issue with this code
class LazyClass
{
public void DoSomething() { }
}
class SomeClass
{
public event EventHandler WatchOut = (s, ea) => { };
public void Start()
{
WatchOut(this, EventArgs.Empty);
}
}
class LazyInterceptor
{
Lazy<LazyClass> lazy;
public LazyInterceptor(Lazy<LazyClass> lazy)
{
this.lazy = lazy;
}
public void Register(SomeClass some)
{
some.WatchOut += (s, ea) => lazy.Value.DoSomething();
}
}
[TestMethod]
public void LazyAndEvents()
{
var builder = new ContainerBuilder();
builder.RegisterType<LazyClass>().SingleInstance();
var container = builder.Build();
var someClass = new SomeClass();
using (var inner = container.BeginLifetimeScope(cb =>
cb.RegisterType().SingleInstance()))
{
var interceptor = inner.Resolve();
interceptor.Register(someClass);
}
someClass.Start();
}
I know of three workarounds around this, but they all seem just wrong
not disposing container - this is what I currently do, but that's just to make Autofac happy
explicitly registering lazy - seems just wrong and I don't even know what will be resolved
taking ownership for dispose - it doesn't seem as bad, but I don't use object in that way, so again it looks like a workaround. Also, in Autofac it introduces dependency which is not nice
The whole point of lifetime scopes is that to control the lifetime of the contained instances. Building on the Disposable pattern, disposing the container is a clean and well-established way of releasing the resources governed by that container. Thus, when a lifetime scope is disposed you should no longer depend on instances resolved from that lifetime scope.
So I would say that you are definitively using Autofac the wrong way here. Perhaps if you explained why you want to use the scope like that, we could figure out the proper usage.

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