Using NCache Extension for SignalR

NCache extends the IDependencyResolver DependencyResolver() method with its UseNCache() method which requires just the cache name and event key for the item added. This acts as the registration point for the clients against the SignalR implementation.

UseNCache() takes in the following parameters:

Parameters	Type	Description
cacheName	string	Name of the cache in NCache which will store the respective item for the client to trace updates via itemVersion.
eventKey	string	Unique, user specified key attribute for the item added to NCache on client registration. Event key is specific to the application. Each client of the application will use the same event key while calling NCache's extension method.
configuration	NCacheScaleoutConfiguration	An object of NCacheScaleoutConfiguration which extends the ScaleoutConfiguration class and takes in cacheName and eventKey as members.

To utilize SignalR in your application:

Install NuGet Package

Install the Alachisoft.NCache.SignalR NuGet package to your application by executing the following command in the Package Manager Console:

Install-Package Alachisoft.NCache.SignalR

Include Namespaces

To utilize the extension, include the following namespaces in your application in Startup.cs:

• Alachisoft.NCache.SignalR
• Microsoft.AspNet.SignalR

Modify Web.config

Define the cacheName and eventKey in the <appSettings> tag in Web.config of your application:

<configuration>

  <appSettings>
    <add key="cache" value="myPartitionedCache"/>
    <add key="eventKey" value="Chat"/>
  </appSettings>

</configuration>

Register Clients to use NCache

Register an instance of the UseNCache() method in Startup.csof your application in either of the following overloads:

Overload 1:

public static IDependencyResolver UseNCache(this IDependencyResolver resolver, string cacheName, string eventKey);

public class Startup
{
    public void Configuration(IAppBuilder app)
    {
        string cache, eventKey;   
        cache = ConfigurationManager.AppSettings["cache"];
        eventKey = ConfigurationManager.AppSettings["eventKey"];            

        GlobalHost.DependencyResolver.UseNCache(cache, eventKey); //using NCache SignalR

        app.MapSignalR();
    }
}

Overload 2:

public static IDependencyResolver UseNCache(this IDependencyResolver resolver, NCacheScaleoutConfiguration configuration);

public class Startup
{
    public void Configuration(IAppBuilder app)
    {
        string cache, eventKey;  
        cache = ConfigurationManager.AppSettings["cache"];
        eventKey = ConfigurationManager.AppSettings["eventKey"];     

        NCacheScaleoutConfiguration configuration = new NCacheScaleoutConfiguration(cache, eventKey);

        GlobalHost.DependencyResolver.UseNCache(configuration); //using NCache SignalR

        app.MapSignalR();
    }
}

See Also

ASP.​NET Session State Provider for NCache

View State Caching

Multi-Region ASP.NET Session State Provider for NCache