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asp.net web api - Ninject.ActivationException thrown only on first web request (WebAPI 2, OWIN 3, Ninject 3)

I am attempting to create a "barebones" Web API project that uses OWIN middleware, Ninject Depencency Injection, and ultimately to be hosted in IIS. I have followed instructions found in an article, "Befriending ASP.NET Web.API2, OWIN and Ninject," here: http://www.alexzaitzev.pro/2014/11/webapi2-owin-and-ninject.html, except I used an empty Web Application Project, and did not tick the "Include Web API references and folders" when creating the project.

When I fire up the new API and make a page request, I get the following Ninject.ActivationException thrown:

Server Error in '/' Application.

Error activating HttpConfiguration
More than one matching bindings are available.
Matching bindings:
 1) binding from HttpConfiguration to method
 2) binding from HttpConfiguration to constant value
Activation path:
 1) Request for HttpConfiguration

Suggestions:
 1) Ensure that you have defined a binding for HttpConfiguration only once.

This exception goes away when I refresh my browser. I really don't understand what is causing this exception. From my point of view, being somewhat inexperienced with WebAPI in OWIN context and Ninject, it's hard to know where the problem lies. Is it with Ninject...? Is it in OWIN...? Is it in WebAPI...?

This is the content of my Startup.cs file:

using System.Web.Http;
using LHD.API_2;
using Microsoft.Owin;
using Microsoft.Owin.Security.OAuth;
using Ninject.Web.Common.OwinHost;
using Ninject.Web.WebApi.OwinHost;
using Owin;

[assembly: OwinStartup(typeof(Startup))]

namespace LHD.API_2
{
    public class Startup
    {
        public void Configuration(IAppBuilder app)
        {
            HttpConfiguration config = new HttpConfiguration();

            // Web API configuration and services
            // Configure Web API to use only bearer token authentication.
            config.SuppressDefaultHostAuthentication();
            config.Filters.Add(new HostAuthenticationFilter(OAuthDefaults.AuthenticationType));

            // Web API routes
            config.MapHttpAttributeRoutes();
            config.Routes.MapHttpRoute("API Default", "api/1/{controller}/{action}/{id}", new { id = RouteParameter.Optional });

            app.UseNinjectMiddleware(() => NinjectConfig.CreateKernel.Value);
            app.UseNinjectWebApi(config);
        }
    }
}

This is the content of my NinjectConfig.cs file:

using System;
using System.Reflection;
using Ninject;

namespace LHD.API_2
{
    public static class NinjectConfig
    {
        public static Lazy<IKernel> CreateKernel = new Lazy<IKernel>(() =>
        {
            StandardKernel kernel = new StandardKernel();
            kernel.Load(Assembly.GetExecutingAssembly());

            RegisterServices(kernel);

            return kernel;
        });

        private static void RegisterServices(KernelBase kernel)
        {
            // TODO - put in registrations here...

            //kernel.Bind<IFakeService>().To<FakeService>();
        }
    }
}

This is the content of my packages.config:

<?xml version="1.0" encoding="utf-8"?>
<packages>
  <package id="Microsoft.AspNet.WebApi" version="5.0.0" targetFramework="net451" />
  <package id="Microsoft.AspNet.WebApi.Client" version="5.2.3" targetFramework="net451" />
  <package id="Microsoft.AspNet.WebApi.Core" version="5.2.3" targetFramework="net451" />
  <package id="Microsoft.AspNet.WebApi.Owin" version="5.2.3" targetFramework="net451" />
  <package id="Microsoft.AspNet.WebApi.WebHost" version="5.0.0" targetFramework="net451" />
  <package id="Microsoft.Owin" version="3.0.1" targetFramework="net451" />
  <package id="Microsoft.Owin.Host.SystemWeb" version="3.0.1" targetFramework="net451" />
  <package id="Newtonsoft.Json" version="6.0.4" targetFramework="net451" />
  <package id="Ninject" version="3.2.0.0" targetFramework="net451" />
  <package id="Ninject.Extensions.ContextPreservation" version="3.2.0.0" targetFramework="net451" />
  <package id="Ninject.Extensions.NamedScope" version="3.2.0.0" targetFramework="net451" />
  <package id="Ninject.Web.Common" version="3.2.0.0" targetFramework="net451" />
  <package id="Ninject.Web.Common.OwinHost" version="3.2.3.0" targetFramework="net451" />
  <package id="Ninject.Web.WebApi" version="3.2.0.0" targetFramework="net451" />
  <package id="Ninject.Web.WebApi.OwinHost" version="3.2.4.0" targetFramework="net451" />
  <package id="Owin" version="1.0" targetFramework="net451" />
</packages>

... and, for the sake of completeness, the content of my web.config is similarly unspectacular:

<?xml version="1.0" encoding="utf-8"?>
<!--
  For more information on how to configure your ASP.NET application, please visit
  http://go.microsoft.com/fwlink/?LinkId=169433
  -->
<configuration>
    <system.web>
        <compilation debug="true" targetFramework="4.5.1" />
        <httpRuntime targetFramework="4.5.1" />
    </system.web>

    <runtime>
        <assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
            <dependentAssembly>
                <assemblyIdentity name="Microsoft.Owin" publicKeyToken="31bf3856ad364e35" culture="neutral" />
                <bindingRedirect oldVersion="0.0.0.0-3.0.1.0" newVersion="3.0.1.0" />
            </dependentAssembly>
            <dependentAssembly>
                <assemblyIdentity name="System.Web.Http" publicKeyToken="31bf3856ad364e35" culture="neutral" />
                <bindingRedirect oldVersion="0.0.0.0-5.2.3.0" newVersion="5.2.3.0" />
            </dependentAssembly>
            <dependentAssembly>
                <assemblyIdentity name="System.Web.Http.Owin" publicKeyToken="31bf3856ad364e35" culture="neutral" />
                <bindingRedirect oldVersion="0.0.0.0-5.2.3.0" newVersion="5.2.3.0" />
            </dependentAssembly>
            <dependentAssembly>
                <assemblyIdentity name="System.Net.Http.Formatting" publicKeyToken="31bf3856ad364e35" culture="neutral" />
                <bindingRedirect oldVersion="0.0.0.0-5.2.3.0" newVersion="5.2.3.0" />
            </dependentAssembly>
        </assemblyBinding>
    </runtime>
<system.webServer>
    <handlers>
      <remove name="ExtensionlessUrlHandler-Integrated-4.0" />
      <remove name="OPTIONSVerbHandler" />
      <remove name="TRACEVerbHandler" />
      <add name="ExtensionlessUrlHandler-Integrated-4.0" path="*." verb="*" type="System.Web.Handlers.TransferRequestHandler" preCondition="integratedMode,runtimeVersionv4.0" />
    </handlers>
  </system.webServer>
</configuration>

Can anyone point me towards what I'm doing wrong, or more importantly, what I can change to get things working without the exception being thrown?

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1 Answer

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What version of the Ninject.Web.WebApi library are you using? it looks like 2 weeks ago a change was made to move some things around. before this change (v3.2.3 and earlier), HttpConfiguration bindings were present in 2 different modules in Ninject.Web.WebApi.OwinHost.OwinWebApiModule and Ninject.Web.WebApi.WebApiModule. after this change (new version is 3.2.4), this binding only happens once.


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