IdentityServerOptions PublicOrigin

Question

Slowly migrating system up from .net core 2.1 to 3.1. While updating IdentityServer4 to 3.1 version. I've stucked into problem method AddIdentityServer where options are specified..

var builder = services.AddIdentityServer(options =>
{             
    (!string.IsNullOrWhiteSpace(identityServerSettingsConfig.PublicOrigin))
    {
        options.PublicOrigin = identityServerSettingsConfig.PublicOrigin;
    }
})

Error: 'IdentityServerOptions' does not contain a definition for 'PublicOrigin' and no accessible extension method 'PublicOrigin' accepting a first argument of type 'IdentityServerOptions' could be found

Installed packages:

    <PackageReference Include="IdentityServer4" Version="4.1.2" />
    <PackageReference Include="IdentityServer4.AccessTokenValidation" Version="3.0.1" />
    <PackageReference Include="IdentityServer4.AspNetIdentity" Version="4.1.2" />
    <PackageReference Include="IdentityServer4.EntityFramework" Version="2.5.3" />
    <PackageReference Include="Microsoft.AspNetCore.App" />
    <PackageReference Include="Microsoft.AspNetCore.Identity.EntityFrameworkCore" Version="5.0.5" />
    <PackageReference Include="Microsoft.AspNetCore.Identity.UI" Version="3.1.0" />
    <PackageReference Include="Microsoft.AspNetCore.Mvc.NewtonsoftJson" Version="3.1.0" />
    <PackageReference Include="Microsoft.EntityFrameworkCore.Design" Version="3.1.0">

Answer 1

The IdentityServerOptions.PublicOrigin property was removed in IdentityServer4 1.0 back in 2016.

This GitHub issue is asking the same question as yourself: https://github.com/IdentityServer/IdentityServer4/issues/4535

One of IdentityServer's authors said it was removed and explained why - and how you can work-around it (assuming you actually need it, I mention this because you probably don't need to restore this functionality):

leastprivilege commented on 19 Jun 2020:

It's gone. It was a hack - please use the forwarded headers approach in ASP.NET Core from now on.

The workaround is to add a middleware step that calls HttpContextExtensions.SetIdentityServerOrigin at the beginning of your pipeline, so it should look something like this:

• In the code-block below, add the code between the //------- comments.
• I included other Configure pipeline/appBuilder methods from one of my own IS4 projects so you can see a complete example.

using IdentityServer4.Extensions; // For IS4's `HttpContextExtensions`

public class Startup
{
    // ...

    public void Configure( IApplicationBuilder app, IWebHostEnvironment env, IHostApplicationLifetime applicationLifetime )
    {
        _ = app
            //-------------------------------- Add the code below this line
            .Use( async (ctx, next) =>
            {
                ctx.SetIdentityServerOrigin( "https://example.com" );
                await next();
            })
            //-------------------------------- Add the code above this line

            .UseCors()
            .UseAuthentication()
            .UseOpenApi()
            .UseSwaggerUi3()
            .UseIdentityServer()
            .UseRouting()
            .UseAuthorization()
            .UseEndpoints( routeBuilder =>
            {
                _ = routeBuilder.MapControllers();
            } )
            .UseStaticFiles();
    }
}