Fixes for hosting in subfolder.

backend/i18n/source/backend_en.json

@@ -291,8 +291,8 @@
   "setup.ruleHttps.failure": " You are not accessing the site over https. If this warning is not correct then Squidex cannot detect https mode, because your instance is behind a reverse proxy such as nginx. Ensure that http headers are forwarded properly, via the <code>X-Forwarded-*</code> headers.",
   "setup.ruleHttps.success": "Congratulations, you are accessing your Squidex installation over a secure connection (https).",
   "setup.rules.headline": "System Checklist",
-  "setup.ruleUrl.failure": "You should access Squidex only over one one canonical URL and configure this URL over the <code>URLS__BASEURL</code> environment variable. The current base URL <code>{actual}</code> does not match to the base url <code>{configured}</code>.",
-  "setup.ruleUrl.success": "Congratulations the <code>URLS__BASEURL</code> environment variable is configured properly.",
+  "setup.ruleUrl.failure": "You should access Squidex only over one canonical URL and configure this URL with the <code>URLS__BASEURL</code> environment variable. The current base URL <code>{actual}</code> does not match to the base url <code>{configured}</code>.",
+  "setup.ruleUrl.success": "Congratulations, the <code>URLS__BASEURL</code> environment variable is configured properly.",
   "setup.title": "Installation",
   "users.accessDenied.text": "This operation is not allowed, your account might be locked.",
   "users.accessDenied.title": "Access denied",

backend/src/Squidex.Shared/Texts.nl.resx

@@ -959,10 +959,10 @@
     <value>System Checklist</value>
   </data>
   <data name="setup.ruleUrl.failure" xml:space="preserve">
-    <value>You should access Squidex only over one one canonical URL and configure this URL over the &lt;code&gt;URLS__BASEURL&lt;/code&gt; environment variable. The current base URL &lt;code&gt;{actual}&lt;/code&gt; does not match to the base url &lt;code&gt;{configured}&lt;/code&gt;.</value>
+    <value>You should access Squidex only over one canonical URL and configure this URL with the &lt;code&gt;URLS__BASEURL&lt;/code&gt; environment variable. The current base URL &lt;code&gt;{actual}&lt;/code&gt; does not match to the base url &lt;code&gt;{configured}&lt;/code&gt;.</value>
   </data>
   <data name="setup.ruleUrl.success" xml:space="preserve">
-    <value>Congratulations the &lt;code&gt;URLS__BASEURL&lt;/code&gt; environment variable is configured properly.</value>
+    <value>Congratulations, the &lt;code&gt;URLS__BASEURL&lt;/code&gt; environment variable is configured properly.</value>
   </data>
   <data name="setup.title" xml:space="preserve">
     <value>Installation</value>

backend/src/Squidex.Shared/Texts.resx

@@ -959,10 +959,10 @@
     <value>System Checklist</value>
   </data>
   <data name="setup.ruleUrl.failure" xml:space="preserve">
-    <value>You should access Squidex only over one one canonical URL and configure this URL over the &lt;code&gt;URLS__BASEURL&lt;/code&gt; environment variable. The current base URL &lt;code&gt;{actual}&lt;/code&gt; does not match to the base url &lt;code&gt;{configured}&lt;/code&gt;.</value>
+    <value>You should access Squidex only over one canonical URL and configure this URL with the &lt;code&gt;URLS__BASEURL&lt;/code&gt; environment variable. The current base URL &lt;code&gt;{actual}&lt;/code&gt; does not match to the base url &lt;code&gt;{configured}&lt;/code&gt;.</value>
   </data>
   <data name="setup.ruleUrl.success" xml:space="preserve">
-    <value>Congratulations the &lt;code&gt;URLS__BASEURL&lt;/code&gt; environment variable is configured properly.</value>
+    <value>Congratulations, the &lt;code&gt;URLS__BASEURL&lt;/code&gt; environment variable is configured properly.</value>
   </data>
   <data name="setup.title" xml:space="preserve">
     <value>Installation</value>

backend/src/Squidex.Web/Pipeline/SetupMiddleware.cs

@@ -25,7 +25,9 @@ namespace Squidex.Web.Pipeline
         {
             if (!isUserFound && await userService.IsEmptyAsync())
             {
-                context.Response.Redirect("/identity-server/setup");
+                var url = context.Request.PathBase.Add("/identity-server/setup");
+
+                context.Response.Redirect(url);
             }
             else
             {

backend/src/Squidex/Areas/IdentityServer/Controllers/Setup/SetupController.cs

@@ -20,6 +20,7 @@ using Squidex.Infrastructure;
 using Squidex.Infrastructure.Reflection;
 using Squidex.Infrastructure.Translations;
 using Squidex.Infrastructure.Validation;
+using Squidex.Web;
 
 namespace Squidex.Areas.IdentityServer.Controllers.Setup
 {
@@ -99,12 +100,10 @@ namespace Squidex.Areas.IdentityServer.Controllers.Setup
         {
             var externalProviders = await SignInManager.GetExternalProvidersAsync();
 
-            var request = HttpContext.Request;
-
             var result = new SetupVM
             {
                 BaseUrlConfigured = urlGenerator.BuildUrl(string.Empty, false),
-                BaseUrlCurrent = $"{request.Scheme}://{request.Host}",
+                BaseUrlCurrent = GetCurrentUrl(),
                 ErrorMessage = errorMessage,
                 EverybodyCanCreateApps = !uiOptions.OnlyAdminsCanCreateApps,
                 IsValidHttps = HttpContext.Request.IsHttps,
@@ -121,5 +120,19 @@ namespace Squidex.Areas.IdentityServer.Controllers.Setup
 
             return result;
         }
+
+        private string GetCurrentUrl()
+        {
+            var request = HttpContext.Request;
+
+            var url = $"{request.Scheme}://{request.Host}{request.PathBase}";
+
+            if (url.EndsWith(Constants.PrefixIdentityServer, StringComparison.Ordinal))
+            {
+                url = url[0..^Constants.PrefixIdentityServer.Length];
+            }
+
+            return url.TrimEnd('/');
+        }
     }
 }