I have tried almost everything, but I cannot get AutoMapper to map A => B when B doesn't have a parameterless constructor.
I'm using Unity and all the dependencies are registered conveniently but, how do I say to AutoMapper "hey, if the target instance needs some dependency in the constructor, ask Unity to build it, and do the mapping later.
I've tried with
Mapper.Initialize(configuration =>
{
configuration.ConstructServicesUsing(container.Resolve);
configuration.CreateMap<Person, PersonViewModel>();
});
But it doesn't work :(
EDIT: In fact, I lied a bit. I'm not using Unity. I'm using Grace, but didn't want to come up with a relatively unknown container asking about advances topics :)
I've solved the problem and it works as smooth as silk. The exact code is like this. Keep in mind that I'm using the Grace IoC Container (which I eagerly recommend).
Bootstrapper.Instance.Configure(new CompositionRoot());
Mapper.Configuration.ConstructServicesUsing(type => Bootstrapper.Instance.Container.Locate(type));
Mapper.CreateMap<Person, PersonViewModel>()
.ConstructUsingServiceLocator();
Like this:
configuration.CreateMap<Person, PersonViewModel>()
.ConstructUsingServiceLocator();
Do this for each mapping that should be created by your service locator.
Related
This is not the first time I work with Inversify, but never had a problem like such. Currently what I have in my project is just a bunch of decorated (properly, constructor injections) services, therefore I assume it's failing on building the metadata.
I'm getting Error: #inject called with undefined this could mean that the class X has a circular dependency problem. You can use a LazyServiceIdentifer to overcome this limitation. whenever I start the application (bear in mind - I don't have a container yet).
Following the "circular dependency problem" part I built a dependency graph using dependency-graph package and it shows no circular dependencies in my project, it also managed to properly generate registration order.
I'm wondering if there's any way to avoid using LazyServiceIdentifier everywhere in the project?
Additionaly I'm trying to understand how is it even possible for this error to occur when using constructor injection (and having no circular dependencies of course)?
I am working with the Owned type as found here: Strong reference of Autofac 2
I'm also using Quartz scheduler, MSMQ, and EF.
My config looks as follows. I've clearly got something wrong as the context that gets injected to the repositories is a different instance than the one given to the service.
builder.RegisterType<EmailAllocationJob>();
builder.RegisterGeneric(typeof(JobWrapper<>));
builder.RegisterType<DataContext>().InstancePerOwned<EmailAllocationJob>();
builder.RegisterType<DataContext>().As<IUnitOfWork>();
builder.RegisterType<EmailAccountRepository>().As<IEmailAccountRepository>();
builder.RegisterType<EmailMessageRepository>().As<IEmailMessageRepository>();
builder.RegisterType<EmailMessageQueue>().As<IEmailMessageQueue>();
builder.RegisterType<EmailAllocationService>().As<IEmailAllocationService>();
I can't for the life of me figure out how to get the configuration fixed. I'd reckon it's the line:
builder.RegisterType<DataContext>().As<IUnitOfWork>();
What I want to say is something like:
builder.RegisterType<DataContext>().As<IUnitOfWork>().InstancePerOwned<EmailAllocationJob>();
Thanks in advance if you can help.
Ok I got it. Needed the line:
builder.RegisterType<DataContext>().InstancePerOwned<EmailAllocationJob>()
.As<IUnitOfWork>().AsSelf();
So it seems important that the DataContext features as the generic argument to RegisterType ONCE, and that the method calls to As<>() and AsSelf() are to be daisy chained in a single statement. Seems obvious now, with a fresh head following yesterday evening.
After migrating to Play-2.1 I stuck into problem that routes compiler stopped working for my routes file. It's been completely fine with Play-2.0.4, but now I'm getting the build error and can't find any workaround for it.
In my project I'm using cake pattern, so controller actions are visible not through <package>.<controller class>.<action>, but through <package>.<component registry>.<controller instance>.<action>. New Play routes compiler is using all action path components except for the last two to form package name that will be used in managed sources (as far as I can get code in https://github.com/playframework/Play20/blob/2.1.0/framework/src/routes-compiler/src/main/scala/play/router/RoutesCompiler.scala). In my case it leads to situation when <package>.<component registry> is chosen as package name, which results in error during build:
[error] server/target/scala-2.10/src_managed/main/com/grumpycats/mmmtg/componentsRegistry/routes.java:5: componentsRegistry is already defined as object componentsRegistry
[error] package com.grumpycats.mmmtg.componentsRegistry;
I made the sample project to demonstrate this problem: https://github.com/rmihael/play-2.1-routes-problem
Is it possible to workaround this problem somehow without dropping cake pattern for controllers? It's the pity that I can't proceed with Play 2.1 due to this problem.
Because of reputation I can not create a comment.
The convention is that classes and objects start with upper case. This convention is applied to pattern matching as well. Looking at a string there seems to be no difference between a package object and normal object (appart from the case). I am not sure how Play 2.1 handles things, that's why this is not an answer but a comment.
You could try the new # syntax in the router. That allows you to create an instance from the Global class. You would still specify <package>.<controller class>.<action>, but in the Global you get it from somewhere else (for example a component registry).
You can find a bit of extra information here under the 'Managed Controller classes instantiation': http://www.playframework.com/documentation/2.1.0/Highlights
This demo project shows it's usage: https://github.com/guillaumebort/play20-spring-demo
I'm newly experimenting with the cryptography application block while using Autofac as the container.
As a result, I'm using the nuget package EntLibContrib 5.0 - Autofac Configurator.
With the DPAPI Symmetric Crypto Provider, I was able to encrypt/decrypt data just fine.
However, with RijndaelManaged, I receive an ActivationException:
Microsoft.Practices.ServiceLocation.ActivationException: Activation error occured while trying to get instance of type ISymmetricCryptoProvider, key "RijndaelManaged" ---> Autofac.Core.Registration.ComponentNotRegisteredException: The requested service 'RijndaelManaged (Microsoft.Practices.EnterpriseLibrary.Security.Cryptography.ISymmetricCryptoProvider)' has not been registered. To avoid this exception, either register a component to provide the service, check for service registration using IsRegistered(), or use the ResolveOptional() method to resolve an optional dependency.
Per instructions here: http://msdn.microsoft.com/en-us/library/ff664686(v=pandp.50).aspx
I am trying to inject CryptographyManager into MyService.
My bootstrapping code looks like this:
var builder = new ContainerBuilder();
builder.RegisterEnterpriseLibrary();
builder.RegisterType<MyService>().As<IMyService>();
_container = builder.Build();
var autofacLocator = new AutofacServiceLocator(_container);
EnterpriseLibraryContainer.Current = autofacLocator;
App.config has this info defined for symmetricCryptoProviders:
name: RijndaelManaged
type: Microsoft.Practices.EnterpriseLibrary.Security.Cryptography.HashAlgorithmProvider, Microsoft.Practices.EnterpriseLibrary.Security.Cryptography, Version=5.0.505.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35
algorithmType:System.Security.Cryptography.RijndaelManaged
protectedKeyFilename:[path_to_my_key]
protectedKeyProtectionScope: LocalMachine
Anyone have experience in this combination of technologies?
After some testing, I believe I may go with a Unity container instead, since I have no preference in IOC containers other than whatever I use should integrate nicely with ASP.NET MVC3 and http-hosted WCF services.
My bootstrapping code then becomes more simple:
var container = new UnityContainer()
.AddNewExtension<EnterpriseLibraryCoreExtension>();
container.RegisterType<IMyService, MyService>();
I actually wrote the Autofac EntLib configurator (with some help from some of the P&P folks). It's been tested with the exception handling block and logging block, but I haven't tried it with the cryptography stuff.
EntLib has an interesting thing where it sometimes requires registered services to be named, and I'm guessing from the exception where it says...
type ISymmetricCryptoProvider, key "RijndaelManaged"
...I'm thinking EntLib wants you to register a named service, like:
builder.Register(c =>
{
// create the HashAlgorithmProvider using
// RijndaelManaged algorithm
})
.Named<ISymmetricCryptoProvider>("RijndaelManaged");
I'm sort of guessing at the exact registration since, again, I've not got experience with it or tested it, but the idea is that EntLib is trying to register a named service whereas the actual service isn't getting registered with the name.
The RegisterEnterpriseLibrary extension basically goes through and tries to use the same algorithm that Unity uses to do the named/unnamed registrations. I'm guessing you've encountered an edge case where something's not getting handled right. EntLib is pretty well tied to Unity, even if they did try to abstract it away.
If you're not tied to Autofac, Unity is going to be your lowest-friction path forward. I like the ease of use and more lightweight nature of Autofac, and my apps are tied to it, so I needed everything to work that way; if you don't have such an affinity, might be easier to just use Unity.
Sorry that's not a super answer. EntLib wire-up in IoC is a really complex beast.
I am starting to learn, MEF and one important thing in it is that I can mark some item (class, propety,method) with Export attribute so that, who ever wants use it will create Import attribute on an instance varaible and use it. How does this mapping happen and when does it happen? Is the import happen lazily on demand or all the composition happen at the start up? Sorry for the ignorant question, I am trying to understand the flow.
It happens in a phase called "Composition". First you create a container and load all your possible sources of parts into it, and then you Compose it. When you do the composition, it resolves all the dependencies and throws an exception if it can't resolve them all properly.
In general, your parts get instantiated during composition (and if you set a break point in the constructor of your part classes, you will see the break point hit during your call to Compose()). However, you can override this in a straightforward way if you use Lazy<T> as the type of your import (assuming you exported your part as type T).
To see how the composition works, take a look at the Compose() method here.