Allowing Configure method to be inherited by Startup class

[matthewhancock]

I'm going to have multiple web applications sharing base code and it would be great if the Startup class could inherit the Configure method from a parent class. Otherwise, I'm going to have to copy and paste the same boilerplate.

e.g. this wouldn't fail

    public class Startup : StartupTemplate
    {
        public override async Task ProcessRequestAsync(HttpContext Context)
        {
            await Context.Response.WriteAsync("Hello World");
        }
    }
    public abstract class StartupTemplate
    {
        public void Configure(IApplicationBuilder app)
        {
            app.Run(ProcessRequestAsync);
        }
        public abstract Task ProcessRequestAsync(HttpContext Context);
    }

This returns the basic Configure not found error:

    System.Exception: TODO: ConfigureDevelopment or Configure method not found
    at Microsoft.AspNet.Hosting.Startup.StartupLoader.LoadStartup(String applicationName, String environmentName, IList`1 diagnosticMessages)

It looks like the update would need to be here: https://github.com/aspnet/Hosting/blob/dev/src/Microsoft.AspNet.Hosting/Startup/StartupLoader.cs

    var methodInfo = startupType.GetTypeInfo().GetDeclaredMethod(methodNameWithEnv)
    ?? startupType.GetTypeInfo().GetDeclaredMethod(methodNameWithNoEnv);

Could GetDeclaredMethod be replaced with GetMethod(String, BindingFlags)?

[dtkujawski]

I ran into this same issue and also believe that not requiring declared methods is a good idea so that we can derive the Startup.cs file from a base class.

Changing the line method above to the following would be nice:

var methodInfo = startupType.GetTypeInfo().GetMethod(methodNameWithEnv, BindingFlags.Public | BindingFlags.Instance)
        ?? startupType.GetTypeInfo().GetMethod(methodNameWithNoEnv, BindingFlags.Public | BindingFlags.Instance);

[glennc]

We are ok with taking this change if either of you guys want to submit a pull request, see the instructions if you haven't done it before.

[dtkujawski]

My first time doing a pull request, so let me know if I did it wrong: #153

[Eilon]

#153 fixed this.