I'm using Web.api and Unity and I am getting the following error when trying to open the default "help" area:
[InvalidOperationException: The type String cannot be constructed. You must configure the container to supply this value.]
Microsoft.Practices.ObjectBuilder2.DynamicMethodConstructorStrategy.GuardTypeIsNonPrimitive(IBuilderContext context, SelectedConstructor selectedConstructor) +280
Microsoft.Practices.ObjectBuilder2.DynamicMethodConstructorStrategy.PreBuildUp(IBuilderContext context) +356
Microsoft.Practices.ObjectBuilder2.StrategyChain.ExecuteBuildUp(IBuilderContext context) +260
Microsoft.Practices.ObjectBuilder2.DynamicMethodBuildPlanCreatorPolicy.CreatePlan(IBuilderContext context, NamedTypeBuildKey buildKey) +205
Microsoft.Practices.ObjectBuilder2.BuildPlanStrategy.PreBuildUp(IBuilderContext context) +231
Microsoft.Practices.ObjectBuilder2.StrategyChain.ExecuteBuildUp(IBuilderContext context) +260
Microsoft.Practices.ObjectBuilder2.BuilderContext.NewBuildUp(NamedTypeBuildKey newBuildKey) +250
Microsoft.Practices.Unity.ObjectBuilder.NamedTypeDependencyResolverPolicy.Resolve(IBuilderContext context) +101
BuildUp_System.Web.Http.HttpRouteCollection(IBuilderContext ) +202
Microsoft.Practices.ObjectBuilder2.DynamicMethodBuildPlan.BuildUp(IBuilderContext context) +42
Microsoft.Practices.ObjectBuilder2.BuildPlanStrategy.PreBuildUp(IBuilderContext context) +319
Microsoft.Practices.ObjectBuilder2.StrategyChain.ExecuteBuildUp(IBuilderContext context) +260
Microsoft.Practices.ObjectBuilder2.BuilderContext.NewBuildUp(NamedTypeBuildKey newBuildKey) +250
Microsoft.Practices.Unity.ObjectBuilder.NamedTypeDependencyResolverPolicy.Resolve(IBuilderContext context) +101
BuildUp_System.Web.Http.HttpConfiguration(IBuilderContext ) +202
Microsoft.Practices.ObjectBuilder2.DynamicMethodBuildPlan.BuildUp(IBuilderContext context) +42
Microsoft.Practices.ObjectBuilder2.BuildPlanStrategy.PreBuildUp(IBuilderContext context) +319
Microsoft.Practices.ObjectBuilder2.StrategyChain.ExecuteBuildUp(IBuilderContext context) +260
Microsoft.Practices.ObjectBuilder2.BuilderContext.NewBuildUp(NamedTypeBuildKey newBuildKey) +250
Microsoft.Practices.Unity.ObjectBuilder.NamedTypeDependencyResolverPolicy.Resolve(IBuilderContext context) +101
BuildUp_API.Areas.HelpPage.Controllers.HelpController(IBuilderContext ) +204
Microsoft.Practices.ObjectBuilder2.DynamicMethodBuildPlan.BuildUp(IBuilderContext context) +42
Microsoft.Practices.ObjectBuilder2.BuildPlanStrategy.PreBuildUp(IBuilderContext context) +319
Microsoft.Practices.ObjectBuilder2.StrategyChain.ExecuteBuildUp(IBuilderContext context) +260
Microsoft.Practices.Unity.UnityContainer.DoBuildUp(Type t, Object existing, String name, IEnumerable`1 resolverOverrides) +373
[ResolutionFailedException: Resolution of the dependency failed, type = "API.Areas.HelpPage.Controllers.HelpController", name = "(none)".
Exception occurred while: while resolving.
Exception is: InvalidOperationException - The type String cannot be constructed. You must configure the container to supply this value.
-----------------------------------------------
At the time of the exception, the container was:
Resolving API.Areas.HelpPage.Controllers.HelpController,(none)
Resolving parameter "config" of constructor API.Areas.HelpPage.Controllers.HelpController(System.Web.Http.HttpConfiguration config)
Resolving System.Web.Http.HttpConfiguration,(none)
Resolving parameter "routes" of constructor System.Web.Http.HttpConfiguration(System.Web.Http.HttpRouteCollection routes)
Resolving System.Web.Http.HttpRouteCollection,(none)
Resolving parameter "virtualPathRoot" of constructor System.Web.Http.HttpRouteCollection(System.String virtualPathRoot)
Resolving System.String,(none)
]
Microsoft.Practices.Unity.UnityContainer.DoBuildUp(Type t, Object existing, String name, IEnumerable`1 resolverOverrides) +436
Microsoft.Practices.Unity.UnityContainer.DoBuildUp(Type t, String name, IEnumerable`1 resolverOverrides) +50
Microsoft.Practices.Unity.UnityContainer.Resolve(Type t, String name, ResolverOverride[] resolverOverrides) +48
Microsoft.Practices.Unity.UnityContainerExtensions.Resolve(IUnityContainer container, Type t, ResolverOverride[] overrides) +61
Unity.Mvc4.UnityDependencyResolver.GetService(Type serviceType) +140
System.Web.Mvc.DefaultControllerActivator.Create(RequestContext requestContext, Type controllerType) +87
[InvalidOperationException: An error occurred when trying to create a controller of type 'API.Areas.HelpPage.Controllers.HelpController'. Make sure that the controller has a parameterless public constructor.]
System.Web.Mvc.DefaultControllerActivator.Create(RequestContext requestContext, Type controllerType) +247
System.Web.Mvc.DefaultControllerFactory.GetControllerInstance(RequestContext requestContext, Type controllerType) +438
System.Web.Mvc.DefaultControllerFactory.CreateController(RequestContext requestContext, String controllerName) +226
System.Web.Mvc.MvcHandler.ProcessRequestInit(HttpContextBase httpContext, IController& controller, IControllerFactory& factory) +326
System.Web.Mvc.MvcHandler.BeginProcessRequest(HttpContextBase httpContext, AsyncCallback callback, Object state) +177
System.Web.Mvc.MvcHandler.BeginProcessRequest(HttpContext httpContext, AsyncCallback callback, Object state) +88
System.Web.Mvc.MvcHandler.System.Web.IHttpAsyncHandler.BeginProcessRequest(HttpContext context, AsyncCallback cb, Object extraData) +50
System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +301
System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +155
I am new to unity and am sure I am missing step(s). In webapiconfig.cs:
public static void Register(HttpConfiguration config)
{
config.Routes.MapHttpRoute(
name: "DefaultApi",
routeTemplate: "api/{controller}/{action}/{id}",
defaults: new { id = RouteParameter.Optional }
);
//Custom formatter
config.Formatters.Clear();
config.Formatters.Add(new JSONPFormater());
config.EnableSystemDiagnosticsTracing();
//Setup DI
Bootstrapper.Initialise();
}
Bootstraper.cs(default values)
public static class Bootstrapper
{
public static IUnityContainer Initialise()
{
var container = BuildUnityContainer();
DependencyResolver.SetResolver(new UnityDependencyResolver(container));
return container;
}
private static IUnityContainer BuildUnityContainer()
{
var container = new UnityContainer();
// register all your components with the container here
// it is NOT necessary to register your controllers
// e.g. container.RegisterType<ITestService, TestService>();
RegisterTypes(container);
return container;
}
public static void RegisterTypes(IUnityContainer container)
{
}
}
My attempt at a web.config web.config
<configSections>
<!-- For more information on Entity Framework configuration, visit http://go.microsoft.com/fwlink/?LinkID=237468 -->
<section name="entityFramework" type="System.Data.Entity.Internal.ConfigFile.EntityFrameworkSection, EntityFramework, Version=5.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" requirePermission="false" />
<section name="unity" type="Microsoft.Practices.Unity.Configuration.UnityConfigurationSection, Microsoft.Practices.Unity.Configuration"/>
</configSections>
<connectionStrings>
<add name="DefaultConnection" providerName="System.Data.SqlClient" connectionString="Data Source=(LocalDb)\v11.0;Initial Catalog=aspnet-API-20130708152001;Integrated Security=SSPI;AttachDBFilename=|DataDirectory|\aspnet-API-20130708152001.mdf" />
<add name="<REMOVED>DBEntities" connectionString="metadata=res://*/Models.DAL.<REMOVED>.csdl|res://*/Models.DAL.<REMOVED>.ssdl|res://*/Models.DAL.<REMOVED>.msl;provider=System.Data.SqlClient;provider connection string="data source=<REMOVED>;initial catalog=<REMOVED>;persist security info=True;user id=<REMOVED>;password=<REMOVED>;MultipleActiveResultSets=True;App=EntityFramework"" providerName="System.Data.EntityClient" />
<!--unity setting-->
<unity>
<containers>
<types>
<register type="API.Areas.HelpPage.Controllers.HelpController, API">
<constructor>
<param valu=""></param>
</constructor>
</register>
</types>
</containers>
</unity>
Am I headed in the right direction??
Thanks
Update: helpcontroller.cs:
public class HelpController : Controller
{
public HelpController()
: this(GlobalConfiguration.Configuration)
{
}
public HelpController(HttpConfiguration config)
{
Configuration = config;
}
public HttpConfiguration Configuration { get; private set; }
public ActionResult Index()
{
return View(Configuration.Services.GetApiExplorer().ApiDescriptions);
}
public ActionResult Api(string apiId)
{
if (!String.IsNullOrEmpty(apiId))
{
HelpPageApiModel apiModel = Configuration.GetHelpPageApiModel(apiId);
if (apiModel != null)
{
return View(apiModel);
}
}
return View("Error");
}
}
url I am trying to access: http:// hostname:port/Help
I think a better way is to add InjectionConstructor attribute to the default constructor. This attribute forces unity to use the decorated constructor.
Example:
public class HelpController : Controller
{
private const string ErrorViewName = "Error";
[InjectionConstructor]
public HelpController()
: this(GlobalConfiguration.Configuration)
{
}