Use configured backoffice route if available

src/Umbraco.Cms.Api.Management/Middleware/BackOfficeAuthorizationInitializationMiddleware.cs

@@ -1,10 +1,15 @@
 using Microsoft.AspNetCore.Http;
 using Microsoft.AspNetCore.Http.Extensions;
 using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.Options;
 using Umbraco.Cms.Core;
+using Umbraco.Cms.Core.Configuration.Models;
+using Umbraco.Cms.Core.DependencyInjection;
+using Umbraco.Cms.Core.Hosting;
 using Umbraco.Cms.Core.Routing;
 using Umbraco.Cms.Core.Services;
 using Umbraco.Cms.Infrastructure.Security;
+using Umbraco.Extensions;
 
 namespace Umbraco.Cms.Api.Management.Middleware;
 
@@ -16,15 +21,40 @@ public class BackOfficeAuthorizationInitializationMiddleware : IMiddleware
     private readonly UmbracoRequestPaths _umbracoRequestPaths;
     private readonly IServiceProvider _serviceProvider;
     private readonly IRuntimeState _runtimeState;
+    private readonly IOptions<GlobalSettings> _globalSettings;
+    private readonly IOptions<WebRoutingSettings> _webRoutingSettings;
+    private readonly IHostingEnvironment _hostingEnvironment;
 
+    [Obsolete("Use the non-obsolete constructor. This will be removed in Umbraco 16.")]
     public BackOfficeAuthorizationInitializationMiddleware(
         UmbracoRequestPaths umbracoRequestPaths,
         IServiceProvider serviceProvider,
         IRuntimeState runtimeState)
+    : this(
+        umbracoRequestPaths,
+        serviceProvider,
+        runtimeState,
+        StaticServiceProvider.Instance.GetRequiredService<IOptions<GlobalSettings>>(),
+        StaticServiceProvider.Instance.GetRequiredService<IOptions<WebRoutingSettings>>(),
+        StaticServiceProvider.Instance.GetRequiredService<IHostingEnvironment>()
+        )
+    {
+    }
+
+    public BackOfficeAuthorizationInitializationMiddleware(
+        UmbracoRequestPaths umbracoRequestPaths,
+        IServiceProvider serviceProvider,
+        IRuntimeState runtimeState,
+        IOptions<GlobalSettings> globalSettings,
+        IOptions<WebRoutingSettings> webRoutingSettings,
+        IHostingEnvironment hostingEnvironment)
     {
         _umbracoRequestPaths = umbracoRequestPaths;
         _serviceProvider = serviceProvider;
         _runtimeState = runtimeState;
+        _globalSettings = globalSettings;
+        _webRoutingSettings = webRoutingSettings;
+        _hostingEnvironment = hostingEnvironment;
     }
 
     public async Task InvokeAsync(HttpContext context, RequestDelegate next)
@@ -47,6 +77,7 @@ private async Task InitializeBackOfficeAuthorizationOnceAsync(HttpContext contex
             return;
         }
 
+
         if (_umbracoRequestPaths.IsBackOfficeRequest(context.Request.Path) == false)
         {
             return;
@@ -55,9 +86,13 @@ private async Task InitializeBackOfficeAuthorizationOnceAsync(HttpContext contex
         await _firstBackOfficeRequestLocker.WaitAsync();
         if (_firstBackOfficeRequest == false)
         {
+            Uri? backOfficeUrl = string.IsNullOrWhiteSpace(_webRoutingSettings.Value.UmbracoApplicationUrl) is false
+                ? new Uri($"{_webRoutingSettings.Value.UmbracoApplicationUrl.TrimEnd('/')}{_globalSettings.Value.GetBackOfficePath(_hostingEnvironment).EnsureStartsWith('/')}")
+                : null;
+
             using IServiceScope scope = _serviceProvider.CreateScope();
             IBackOfficeApplicationManager backOfficeApplicationManager = scope.ServiceProvider.GetRequiredService<IBackOfficeApplicationManager>();
-            await backOfficeApplicationManager.EnsureBackOfficeApplicationAsync(new Uri(context.Request.GetDisplayUrl()));
+            await backOfficeApplicationManager.EnsureBackOfficeApplicationAsync(backOfficeUrl ?? new Uri(context.Request.GetDisplayUrl()));
             _firstBackOfficeRequest = true;
         }