NCacheDistributedCache constructor is requesting NCacheSessionConfiguration but only NCacheConfiguration is setup.

In order to use NCache as distributed cache in ASP.NET Core, one would have the following code in ConfigureService() of Startup.cs.

public class Startup
{
    public void ConfigureServices(IServiceCollection services)
    {
        services.AddNCacheDistributedCache(Configuration.GetSection("NCache"));
    }
}

Looking at the source codes of AddNCacheDistributedCache(), it's setting up the configuration NCacheConfiguration.

However, the constructor of NCacheDistributedCache is requesting for NCacheSessionConfiguration, and not NCacheConfiguration.

Since the configuration NCacheSessionConfiguration was never setup, I always receive the exception A valid Cache ID has not been specified. Is there something that I'm missing?

Hi Damien,

Thank you for pointing this out to us and helping us narrow down the cause. I have reproduced the issue and have confirmed with Engineering that it is a bug. You are correct in that the constructor of NCacheDistributedCache should have IOptions<NCacheConfiguration> instead of IOptions<NCacheSessionConfiguration> as parameter.

For your work, there are two possible workarounds:

One method is to use services.AddNCacheSession(Configuration.GetSection("NCache") instead of services.AddSession() after services.AddNCacheDistributedCache(Configuration.GetSection("NCache") in the Startup.cs file as such (Note that I have commented out overloaded extension methods to programmatically include configuration information that you can also use):

public void ConfigureServices(IServiceCollection services)     
{
            services.AddMvc();

           // The following code adds the NCache IDistributedCache provider
            **services.AddNCacheDistributedCache(Configuration.GetSection("NCacheSettings"));**

            // Alternate extension method
            //services.AddNCacheDistributedCache(configuration =>
            //{
            //    configuration.CacheName = "myPartitionedCache";
            //});

           // The following code adds the NCache ASP.NET Core session provider
            **services.AddNCacheSession(Configuration.GetSection("NCacheSettings"));**

            // Alternate extension method 
            //services.AddNCacheSession(configuration =>
            //{
            //    configuration.CacheName = "myPartitionedCache"; 
            //});
        }

After this, in the Configure method, also within the Startup.cs file, you can enable NCache functionality into the request pipeline using the UseNCacheSession extension method as shown in the following example:

public void Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerFactory loggerFactory)
{
      // Some code

       app.UseStaticFiles();

       **app.UseNCacheSession();**

       app.UseMvc(routes =>
           {
                // routes
            });
}

The second possible workaround is to use the NCache source code from GitHub, and use the source code in the NCache-master/Integration/NCacheSessionServices file path. Go to NCacheDistributedCache.cs file, correct the constructor as shown below and then build the solution.

public NCacheDistributedCache(IOptions<**NCacheConfiguration**> options)
{
            // Keep code the same here
}

You can then use the generated DLLs in your project.

By using either of the two workarounds mentioned above, you can then provide the NCache IDistributedCache implementation through dependency injection into any constructor in the app such as a controller class constructor.

The following link contains more information on the different ways NCache can support ASP.NET Core:

http://www.alachisoft.com/resources/docs/ncache/prog-guide/session-storage-aspnet-core.html

I hope this resolves your issues.

Alachisoft / NCache

NCacheDistributedCache constructor is requesting NCacheSessionConfiguration but only NCacheConfiguration is setup. #38