Using appsettings.json to configure Kestrel listen port Dotnet core 2 preview 2

Question

From what I understand the correct way of setting listen ports for ASP Dotnet Core 2 preview 1/2 is by creating a Kestrel section in the appsettings.json in the following format:

"Kestrel": {
    "EndPoints": { //Could also be Endpoints, it's a bit unclear
        "Http": {
        "Address": "127.0.0.1",
    "Port": 9001 //the port you want Kestrel to run on
},

I have tried to set up the sample webapp on a Debian machine, but when I start the app, it writes out that the app is listing on port 5000, the default port..

I know that the appsettings.json is read, because when I change the logging level to Trace, I get more info upon startup, including that no Endpoints are found and the app will use the standard 5000 port.

I have tried to search the aspnet source code on Github, and I can find a area where the Kestrel section is read from configuration (https://github.com/aspnet/Identity/blob/e38759b8a2de1b7a4a1c19462e40214b43c1cf3b/samples/IdentityOIDCWebApplicationSample/MetaPackage/KestrelServerOptionsSetup.cs), but as you can see it looks like a sample project.

What am I missing, isn't this the standard way to configure Kestrel in ASP Dotnet core 2?

Answer 1

As mentioned in a comment on the accepted answer, 2.1 has support for appsettings.json, see https://blogs.msdn.microsoft.com/webdev/2018/02/02/asp-net-core-2-1-roadmap/#security

A working appsettings.json:

"Kestrel": {
  "EndPoints": {
    "Http": {
      "Url": "http://localhost:5555"
    }
  }
}

This is for a Program.cs using (created by "dotnet new webapi"):

WebHost.CreateDefaultBuilder(args)

Relevant source code in GitHub https://github.com/aspnet/MetaPackages/blob/master/src/Microsoft.AspNetCore/WebHost.cs#L163

options.Configure(builderContext.Configuration.GetSection("Kestrel"));

and https://github.com/aspnet/MetaPackages/blob/master/src/Microsoft.AspNetCore/WebHost.cs#L169

config.AddJsonFile("appsettings.json", optional: true, reloadOnChange: true)