Why is IAppBuilder undefined after updating to latest SignalR libraries through NuGet?

Question

I'm in the middle of migrating to .Net 4.5 and SignalR 2.x and ran into some issues/confusion surrounding the Owin dll. I installed the latest verion of SignalR through Nuget with the following: Install-Package Microsoft.AspNet.SignalR

I added the Startup class as described in the migration. However, IAppBuilder started coming up as unresolved.

I checked on StackOverflow and the prescribed solution was to run: Update-Package Owin -Reinstall I did this and the error went away.

However, the application is back to including a reference to Owin 1.0.

I'm a little confused here. Doesn't this conflict with the latest/greatest? Should I be pulling the IAppBuilder definition from a different reference?

Thanks, JB

Answer 1

SignalR 2.0.3 still depends on Owin.dll version 1.0.0.0 just as it has since SignalR 1.0.0.

The only thing defined in Owin.dll is the IAppBuilder interface which hasn't changed since it was introduced. If you look at the NuGet Gallery you'll see that there has only ever been one version of the Owin package.

SignalR also depends on Microsoft.Owin which provides types that make it easier to write Owin middleware. This package has gone through several iterations, and SignalR 2.0.3 depends on Microsoft.Owin 2.0.1.