Umbraco-CMS/src/Umbraco.Cms.ManagementApi/Configuration/ConfigureMvcOptions.cs

using Microsoft.AspNetCore.Mvc;
using Microsoft.Extensions.Options;
using Umbraco.Cms.Core;
using Umbraco.Cms.Core.Configuration.Models;
using Umbraco.New.Cms.Web.Common.Routing;

namespace Umbraco.Cms.ManagementApi.Configuration;

public class ConfigureMvcOptions : IConfigureOptions<MvcOptions>
{
    private readonly IOptions<GlobalSettings> _globalSettings;

    public ConfigureMvcOptions(IOptions<GlobalSettings> globalSettings)
    {
        _globalSettings = globalSettings;
    }

    public void Configure(MvcOptions options)
    {
        // Replace the BackOfficeToken in routes.

        var backofficePath = _globalSettings.Value.UmbracoPath.TrimStart(Constants.CharArrays.TildeForwardSlash);
        options.Conventions.Add(new UmbracoBackofficeToken(Constants.Web.AttributeRouting.BackOfficeToken, backofficePath));

    }
}