URLs/Ports cannot be specified using Configuration as documented

[bcrosnier]

In the Endpoint Configuration section, on how to configure Kestrel endpoints, the page mentions:
"Specify URLs using the: urls host configuration key."

This information is misleading and implies that the Configuration key urls works as intended, which is definitely not the case (aspnet/Hosting#1299)

Funnily enough, one supported way to setup endpoints from configuration, to my knowledge, is used in the appsettings.json example later on in the section (with the IConfiguration key being Kestrel:Endpoints:Http:Url for a HTTP endpoint), but:

1. No explanation whatsoever is offered on how the Kestrel:Endpoints section works,
2. The Endpoint property does not actually exist in KestrelServerOptions (I suppose there's a Configuration binder somewhere),
3. Unlike other means of configuration like the ASPNETCORE_URLS env. var, the UseUrls() method, and the --urls program argument, the Kestrel:Endpoints:Http:Url key only supports a single endpoint, meaning I can't use http://127.0.0.1:12345;http://::1:12345 to listen on both IPv4 and IPv6, to the best of my knowledge.

I just wanted a Urls property somewhere in my IConfiguration. Have I been missing something?

Cheers!

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Erratum 1

All three points are addressed in the Schema notes: section, and a valid configuration for the use case mentioned above looks something like this:

{
  "Kestrel": {
    "Endpoints": {
      "MyHttpV4": {
        "Url": "http://127.0.0.1:12345"
      },
      "MyHttpV6": {
        "Url": "http://[::1]:12345"
      }
    }
  }
}

I propose the urls host configuration key could be modified to explicit this behavior.

---

Document Details

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• ID: f22dcddb-0c25-be1a-9a02-9e71dce86bdb
• Version Independent ID: 3e0e12c2-e544-5655-e001-d2ec180b11a8
• Content: Kestrel web server implementation in ASP.NET Core
• Content Source: aspnetcore/fundamentals/servers/kestrel.md
• Product: aspnet-core
• Technology: aspnetcore-fundamentals
• GitHub Login: @guardrex
• Microsoft Alias: riande

[guardrex]

Hello @bcrosnier ...

I propose the urls host configuration key could be modified to explicit this behavior.

That's product feedback, and we only work on documentation on this repo. You can provide that feedback to the product unit on the engineering repo at https://github.com/dotnet/aspnetcore/issues.

There's in-design/in-progress work in this area, some of the issues are ...

• Setting the ClientCertificateMode Kestrel server option from an appsettings.json file. aspnetcore#18660 – Working on certification configuration via appsettings file.
• Define a JSON schema for appsettings.json aspnetcore#2867 – JSON schema for appsettings.
• Read additional KestrelServerOptions from config aspnetcore#4765 – Additional KestrelServerOptions from config.