I using StructureMap to create instances of ModuleData
I have many classes that inherit from ModuleData(class A,B,C...) and each of them get Config1 or Config2 in coustructor
In Registry(located in file1.cs) I scan all types of ModuleData.
In Get(lacated in file2.cs) I get the instance.
I want that when ObjectFactory creates Config1/Config2 while creating instance of ModuleData it will pass "param" to Config1/Config2 constructors.
How I can configure structuremap to do this?
P.S. Registry & Get methods are located in different files!!!
Thank you
public class Config1
{
Config1(string param)
{
}
}
public class Config2
{
Config2(string param)
{
}
}
//.....//
public class A : ModuleData
{
A(Config1 c)
{
}
}
public class B : ModuleData
{
A(Config2 c)
{
}
}
//....//
//located in file1.cs
public Registry()
{
Scan(x =>
{
x.TheCallingAssembly();
x.AddAllTypesOf<ModuleData>();
});
ObjectFactory.Initialize(x =>
{
x.For<Config1>().Use<Config1>();
x.For<Config2>().Use<Config2>();
});
}
//....//
//located in file2.cs
public ModuleData Get(object o)
{
var module = o as PageModule;
var t = Type.GetType(string.Format("{0}.{1},{2}", Settings.Namespace, module.Name, Settings.Assembly));
return ObjectFactory.With("param").EqualTo(module.Parameters).GetInstance(t) as ModuleData;
}
I can't think of a good way to do what you want, I think its a bit of a design problem... I think you would have to explain a bit more about why you need to do this for me to help you.
What is a page module? Why is your config objects dependent on it?
Based on your comment, I think what you need is a factory object that creates ModuleData objects for you. Since they are objects it does not make much sense to get them from the container. Think about using a data access technology like Entity Framework, it would not make sense to get those objects from the container. From what I can tell, this is a similar case.
Related
I am busy developing my first non-example Orchard module. It is a handful of controllers and views, with custom (EF) data access, and is largely independent of Orchard content types and parts. Normally I set up mappings in an Application_Start handler, but as the actions in this MVC module will be invoked in the context of the Orchard application, I no longer have that point of entry. My most obvious and immediate solution is to move mapping initialization into static constructors for mapped view models, e.g.
public class ApplicantPersonalDetailsModel : MappedViewModel<Applicant>
{
static ApplicantPersonalDetailsModel()
{
Mapper.CreateMap<Applicant, ApplicantPersonalDetailsModel>().Bidirectional();
}
....
}
How else can I do this? is there a better way to do this in MVC3/4 in general, or preferably, an event or hook I can grab in the Orchard application to also achieve this on applicaion startup?
The way I have done it is by implementing IOrchardShellEvents
public class MenuOrchardShellEvents : IOrchardShellEvents
{
public void Activated()
{
Mapper.CreateMap<YSRB.Menu.Models.Records.Customer, YSRB.Menu.Models.ViewModels.CustomerViewModel>()
.ForMember(c => c.CustomerType,
m => m.MapFrom(
x => (CustomerTypes)x.CustomerType
)
);
Mapper.CreateMap<YSRB.Menu.Models.ViewModels.CustomerViewModel, YSRB.Menu.Models.Records.Customer>()
.ForMember(c => c.CustomerType,
m => m.MapFrom(
x => (int)x.CustomerType
)
);
}
public void Terminating()
{
//Do nothing
}
}
Hope this helps.
The Handler is the best place for initializing your variables, even if you haven't defined any part inside your module you can define one without a driver but with handler.
public class InitPartHandler : ContentHandler
{
public InitPartHandler(IRepository<InitPartRecord> repository)
{
OnInitializing<InitPart>((context, part) =>
// do your initialization here
);
}
}
EDIT
InitPart and InitPartRecord would be
public class InitPart : ContentPart<InitPartRecord>
{
}
public class InitPartRecord : ContentPartRecord
{
}
I am about to switch from Windsor to Structuremap for an existing project with ~100 registered components (mostly singletons).
All components inherit from a common base class that provides logging and health tracking and for this reason, contains a "Name" property used to identify component instances.
With Windsor, it was possible to set the component's Name property to the name that was used to register the component in the IOC container (We used a Facility for this).
My question: Is something like this possible with Structuremap?
(I dream of a call to c.For<IFoo>.Use<Bar>.Named("Doe") that magically results in instanceOfBar.Name = "Doe" somewhere.)
Here is what I tried:
using System;
using StructureMap;
using StructureMap.Interceptors;
using System.Diagnostics;
namespace ConsoleApplication1
{
interface IServiceA { }
interface IServiceB { }
class Base
{
public string Name { get; set; }
}
class ComponentA : Base, IServiceA { }
class ComponentB : Base, IServiceB
{
public ComponentB(IServiceA serviceA)
{
this.ServiceA = serviceA;
}
public IServiceA ServiceA { get; private set; }
}
class SetNameInterceptor : TypeInterceptor
{
public bool MatchesType(Type type) { return true; }
public object Process(object target, IContext context)
{
// *** Any other way? This does not work...
string name = context.BuildStack.Current != null ? context.BuildStack.Current.Name : context.RequestedName;
((Base)target).Name = name;
return target;
}
}
class Program
{
static void Main(string[] args)
{
Container container = new Container(c =>
{
c.RegisterInterceptor(new SetNameInterceptor());
c.For<IServiceA>().Use<ComponentA>().Named("A");
c.For<IServiceB>().Use<ComponentB>().Named("B");
});
var b = container.GetInstance<IServiceB>();
// both Fail:
Debug.Assert(((ComponentB)b).Name == "B");
Debug.Assert(((ComponentA)((ComponentB)b).ServiceA).Name == "A");
}
}
}
The above obviously does not work, I tried several variations but had no luck. The registered name of the target object does not seem to be consistently reachable via IContext.
My second best approach would be to define a new "NamedComponent(...)" extension method that resolves to Named(name).WithProperty(x => x.Name).EqualTo(name), but I wonder if this can be avoided to keep component registration as "structuremap-like" as possible?
Am I missing something?
I've never used WithProperty before but if it works the way I'd expect it should do the trick for you.
I think I would favor using EnrichWith though. Something like:
c.For<IFoo>().Use<Foo>().Named(name).EnrichWith(f => f.Name = name);
EnrichWith is a bit more explicit about what it's doing IMO, and lets you call any code on your instance before returning it to the caller. I like that this lets you do a straightforward assignment as well.
There is also a more complex handler you can use with EnrichWith that gives access to the context of the request - this would allow you to do something like this:
c.For<IFoo>().Use<Foo>().Named(name)
.EnrichWith((c, i) => {
i.Name = c.RequestedName;
return i;
});
This may be overkill for your situation but the contextual awareness can be pretty useful.
How do I handle classes with static methods with Ninject?
That is, in C# one can not have static methods in an interface, and Ninject works on the basis of using interfaces?
My use case is a class that I would like it to have a static method to create an
unpopulated instance of itself.
EDIT 1
Just to add an example in the TopologyImp class, in the GetRootNodes() method, how would I create some iNode classes to return? Would I construct these with normal code practice or would I somehow use Ninject? But if I use the container to create then haven't I given this library knowledge of the IOC then?
public interface ITopology
{
List<INode> GetRootNodes();
}
public class TopologyImp : ITopology
{
public List<INode> GetRootNodes()
{
List<INode> result = new List<INode>();
// Need code here to create some instances, but how to without knowledge of the container?
// e.g. want to create a few INode instances and add them to the list and then return the list
}
}
public interface INode
{
// Parameters
long Id { get; set; }
string Name { get; set; }
}
class NodeImp : INode
{
public long Id
{
get { throw new NotImplementedException(); }
set { throw new NotImplementedException(); }
}
public string Name
{
get { throw new NotImplementedException(); }
set { throw new NotImplementedException(); }
}
}
// Just background to highlight the fact I'm using Ninject fine to inject ITopology
public partial class Form1 : Form
{
private ITopology _top;
public Form1()
{
IKernel kernal = new StandardKernel(new TopologyModule());
_top = kernal.Get<ITopology>();
InitializeComponent();
}
}
If you're building a singleton or something of that nature and trying to inject dependencies, typically you instead write your code as a normal class, without trying to put in lots of (probably incorrect) code managing the singleton and instead register the object InSingletonScope (v2 - you didnt mention your Ninject version). Each time you do that, you have one less class that doesnt surface its dependencies.
If you're feeling especially bloody-minded and are certain that you want to go against that general flow, the main tools Ninject gives you is Kernel.Inject, which one can use after you (or someone else) has newd up an instance to inject the dependencies. But then to locate one's Kernelm you're typically going to be using a Service Locator, which is likely to cause as much of a mess as it is likely to solve.
EDIT: Thanks for following up - I see what you're after. Here's a hacky way to approximate the autofac automatic factory mechanism :-
/// <summary>
/// Ugly example of a not-very-automatic factory in Ninject
/// </summary>
class AutomaticFactoriesInNinject
{
class Node
{
}
class NodeFactory
{
public NodeFactory( Func<Node> createNode )
{
_createNode = createNode;
}
Func<Node> _createNode;
public Node GenerateTree()
{
return _createNode();
}
}
internal class Module : NinjectModule
{
public override void Load()
{
Bind<Func<Node>>().ToMethod( context => () => Kernel.Get<Node>() );
}
}
[Fact]
public void CanGenerate()
{
var kernel = new StandardKernel( new Module() );
var result = kernel.Get<NodeFactory>().GenerateTree();
Assert.IsType<Node>( result );
}
}
The ToMethod stuff is a specific application of the ToProvider pattern -- here's how you'd do the same thing via that route:-
...
class NodeProvider : IProvider
{
public Type Type
{
get { return typeof(Node); }
}
public object Create( IContext context )
{
return context.Kernel.Get<Node>();
}
}
internal class Module : NinjectModule
{
public override void Load()
{
Bind<Func<Node>>().ToProvider<NodeProvider>();
}
}
...
I have not thought this through though and am not recommending this as A Good Idea - there may be far better ways of structuring something like this. #Mark Seemann? :P
I believe Unity and MEF also support things in this direction (keywords: automatic factory, Func)
EDIT 2: Shorter syntax if you're willing to use container-specific attributes and drop to property injection (even if Ninject allows you to override the specific attributes, I much prefer constructor injection):
class NodeFactory
{
[Inject]
public Func<Node> NodeFactory { private get; set; }
public Node GenerateTree()
{
return NodeFactory();
}
}
EDIT 3: You also need to be aware of this Ninject Module by #Remo Gloor which is slated to be in the 2.4 release
EDIT 4: Also overlapping, but not directly relevant is the fact that in Ninject, you can request an IKernel in your ctor/properties and have that injected (but that doesn't work directly in a static method).
public class TheController : Controller
{
IThe the;
public TheController( IThe the)
{
//when User.IsInRole("r1") The1 should be injected else r2
this.the = the;
}
}
public class The1 : IThe{}
public class The2 : IThe{}
//anybody knows a good way of doing this ?
IHandlerSelector is the way to go. See this post for an example of usage.
Alternatively if you prefer AutoFac-like experience you can use factory for that:
container.Register(Component.For<IThe>().UsingFactoryMethod(
c => HttpContext.Current.User.IsInRole("r1") ?
c.Resolve<IThe>("r1") :
c.Resolve<IThe>("r2"));
Or if you want to use specific IThe just in one context, you can use DynamicParameters:
container.Register(Component.For<TheFactory>().Lifestyle.Transient.DynamicParameters(
(c, d) => HttpContext.Current.User.IsInRole("r1") ?
d["the"] = c.Resolve<IThe>("r1") :
c.Resolve<IThe>("r2"));
However the most correct way of doing this is IHandlerSelector
The container-agnostic approach obviously employs an Abstract Factory:
public interface ITheFactory
{
IThe Create(IPrincipal user);
}
You can take a dependency on ITheFactory instead of IThe:
public class TheController : Controller
{
private readonly IThe the;
public TheController(ITheFactory theFactory)
{
if (theFactory == null)
{
throw new ArgumentNullException("theFactory");
}
this.the = theFactory.Create(this.User);
}
}
I can't really remember if this.User is populated at this time, but if it isn't, you can just keep a reference to the factory and lazily resolve your dependency the first time it's requested.
However, Controller.User is a bit special because it ought to be available as Thread.CurrentPrincipal as well. This means that in this special case you don't actually have to introduce an Abstract Factory. Instead, you can write a Decorator that performs the selection every time it's used:
public class UserSelectingThe : IThe
{
private readonly IThe the1;
private readonly IThe the2;
public UserSelectingThe(IThe the1, IThe the2)
{
if (the1 == null)
{
throw new ArgumentNullException("the1");
}
if (the2 == null)
{
throw new ArgumentNullException("the2");
}
this.the1 = the1;
this.the2 = the2;
}
// Assuming IThe defines the Foo method:
public Baz Foo(string bar)
{
if (Thread.CurrentPrincipal.IsInRole("r1"))
{
return this.the1.Foo(bar);
}
return this.the2.Foo(bar);
}
}
In this case, you would be able to use your original TheController class unchanged.
In Autofac:
var builder = new ContainerBuilder();
// Give the different implementations names
builder.RegisterType<The1>.Named<IThe>("r1");
builder.RegisterType<The2>.Named<IThe>("r2");
// Use a function for the default IThe
builder.Register(
c => HttpContext.Current.User.IsInRole("r1") ?
c.Resolve<IThe>("r1") :
c.Resolve<IThe>("r2"))
.As<IThe>()
.ExternallyOwned();
If you have a lot of roles, you can use a method instead of the inline expression, e.g.:
builder.Register(c => ChooseTheImplementation(c))
(BTW, The "ExternallyOwned" modifier tells the container that the result of the function is disposed elsewhere, e.g. via the concrete components. You can usually leave it out but it makes good documentation :))
I am using windsor castle as my IoC container, and has run in to a bit of a problem. This is best explained in code, so I´ll give it a try.
I have a factory class, that should provide me with implementations of a certain interface:
public interface IObjectCreatorFactory
{
IObjectCreator GetObjectCreator(Type objectType);
}
public interface IObjectCreator
{
T CreateObject<T>(IDataRow data);
bool SupportsType(Type type);
}
Implementation of the factory class could look like this, though I am not sure this is the way to go:
public interface ObjectCreatorFactory:IObjectCreatorFactory
{
IEnumerable specificCreators;
IObjectCreator defaultCreator;
public ObjectCreatorFactory(IEnumerable<IObjectCreator> specificCreators, IObjectCreator defaultCreator)
{
this.specificCreators= specificCreators;
this.defaultCreator= defaultCreator;
}
public IObjectCreator GetObjectCreator(Type objectType)
{
foreach (IObjectCreator creator in specificCreators)
{
if (creator.SupportsType(objectType))
{
return creator;
}
}
return defaultCreator;
}
}
Now this would work out ok, but if I want my IObjectCreator instance to create child objects using a specific IObjectCreator, i would like to call ObjectCreatorFactory, and this obviously results in a circular reference:
public void SpecificObjectCreator:IObjectCreator
{
IObjectCreatorFactory objCreatorFactory;
public SpecificObjectCreator(IObjectCreatorFactory objCreatorFactory)
{
this.objCreatorFactory = objCreatorFactory;
}
T CreateObject<T>(IDataRow data)
{
T obj = new T;
ChildObject childObject = objCreatorFactory.GetObjectCreator(typeof(ChildObject)).CreateObject<ChildObject>(data);
.......
}
bool SupportsType(Type type);
}
This does not work out. What would be the way to go for this scenario, where the created objects are refering back to the factory for child object creators?
I would simply move the factory out of the constructors of the various specific object creators, and introduce a method on the IObjectCreator interface instead, responsible for initialising the creators:
public interface IObjectCreator
{
T CreateObject<T>(IDataRow data);
bool SupportsType(Type type);
void Initialize(IObjectCreatorFactory factory);
}
And then just invoke Initialze(this) on each object creator passed into the factory.
In the past I've used custom life cycle stages to take care of automatically invoking "post-construction" setup of components to both avoid circular dependencies and also to take care of other associated concerns (i.e. applying additional component configuration from an external source like a database) - but it's probably overkill for what you need.