Fix for ModelsBuilderConfig

src/Umbraco.Configuration/ModelsBuilderConfig.cs

@@ -57,10 +57,8 @@ namespace Umbraco.Configuration
             value = ConfigurationManager.AppSettings[Prefix + "ModelsDirectory"];
             if (!string.IsNullOrWhiteSpace(value))
             {
-                var root = "~/";
-
                 // GetModelsDirectory will ensure that the path is safe
-                ModelsDirectory = GetModelsDirectory(root, value, AcceptUnsafeModelsDirectory);
+                ModelsDirectory = value;
             }
 
             // default: 0
@@ -98,36 +96,7 @@ namespace Umbraco.Configuration
             DebugLevel = debugLevel;
         }
 
-        // internal for tests
-        internal static string GetModelsDirectory(string root, string config, bool acceptUnsafe)
-        {
-            // making sure it is safe, ie under the website root,
-            // unless AcceptUnsafeModelsDirectory and then everything is OK.
 
-            if (!Path.IsPathRooted(root))
-                throw new ConfigurationErrorsException($"Root is not rooted \"{root}\".");
-
-            if (config.StartsWith("~/"))
-            {
-                var dir = Path.Combine(root, config.TrimStart("~/"));
-
-                // sanitize - GetFullPath will take care of any relative
-                // segments in path, eg '../../foo.tmp' - it may throw a SecurityException
-                // if the combined path reaches illegal parts of the filesystem
-                dir = Path.GetFullPath(dir);
-                root = Path.GetFullPath(root);
-
-                if (!dir.StartsWith(root) && !acceptUnsafe)
-                    throw new ConfigurationErrorsException($"Invalid models directory \"{config}\".");
-
-                return dir;
-            }
-
-            if (acceptUnsafe)
-                return Path.GetFullPath(config);
-
-            throw new ConfigurationErrorsException($"Invalid models directory \"{config}\".");
-        }
 
         /// <summary>
         /// Gets a value indicating whether the whole models experience is enabled.

src/Umbraco.Core/Configuration/ModelsBuilderConfigExtensions.cs

@@ -1,12 +1,57 @@
-using Umbraco.Core.IO;
+using System.Configuration;
+using System.IO;
+using Umbraco.Core.IO;
 
 namespace Umbraco.Core.Configuration
 {
     public static class ModelsBuilderConfigExtensions
     {
+        private static string _modelsDirectoryAbsolute = null;
+
         public static string ModelsDirectoryAbsolute(this IModelsBuilderConfig modelsBuilderConfig, IIOHelper ioHelper)
         {
-            return ioHelper.MapPath(modelsBuilderConfig.ModelsDirectory);
+
+            if (_modelsDirectoryAbsolute is null)
+            {
+                var modelsDirectory = modelsBuilderConfig.ModelsDirectory;
+                var root = ioHelper.MapPath("~/");
+
+                _modelsDirectoryAbsolute = GetModelsDirectory(root, modelsDirectory,
+                    modelsBuilderConfig.AcceptUnsafeModelsDirectory);
+            }
+
+            return _modelsDirectoryAbsolute;
+        }
+
+        // internal for tests
+        internal static string GetModelsDirectory(string root, string config, bool acceptUnsafe)
+        {
+            // making sure it is safe, ie under the website root,
+            // unless AcceptUnsafeModelsDirectory and then everything is OK.
+
+            if (!Path.IsPathRooted(root))
+                throw new ConfigurationErrorsException($"Root is not rooted \"{root}\".");
+
+            if (config.StartsWith("~/"))
+            {
+                var dir = Path.Combine(root, config.TrimStart("~/"));
+
+                // sanitize - GetFullPath will take care of any relative
+                // segments in path, eg '../../foo.tmp' - it may throw a SecurityException
+                // if the combined path reaches illegal parts of the filesystem
+                dir = Path.GetFullPath(dir);
+                root = Path.GetFullPath(root);
+
+                if (!dir.StartsWith(root) && !acceptUnsafe)
+                    throw new ConfigurationErrorsException($"Invalid models directory \"{config}\".");
+
+                return dir;
+            }
+
+            if (acceptUnsafe)
+                return Path.GetFullPath(config);
+
+            throw new ConfigurationErrorsException($"Invalid models directory \"{config}\".");
         }
     }
 }

src/Umbraco.Core/Umbraco.Core.csproj

@@ -12,6 +12,7 @@
 
     <ItemGroup>
       <PackageReference Include="System.ComponentModel.Annotations" Version="4.6.0" />
+      <PackageReference Include="System.Configuration.ConfigurationManager" Version="4.6.0" />
       <PackageReference Include="System.Reflection.Emit.Lightweight" Version="4.3.0" />
       <PackageReference Include="System.Runtime.Caching" Version="4.6.0" />
     </ItemGroup>

src/Umbraco.Tests/ModelsBuilder/ConfigTests.cs

@@ -2,7 +2,7 @@
 using NUnit.Framework;
 using Umbraco.Configuration;
 using Umbraco.Core;
-using Umbraco.Tests.TestHelpers;
+using Umbraco.Core.Configuration;
 
 namespace Umbraco.Tests.ModelsBuilder
 {
@@ -35,7 +35,7 @@ namespace Umbraco.Tests.ModelsBuilder
         [TestCase("c:/path/to/root", "c:/another/path/to/elsewhere", true, "c:\\another\\path\\to\\elsewhere")]
         public void GetModelsDirectoryTests(string root, string config, bool acceptUnsafe, string expected)
         {
-            Assert.AreEqual(expected, ModelsBuilderConfig.GetModelsDirectory(root, config, acceptUnsafe));
+            Assert.AreEqual(expected, ModelsBuilderConfigExtensions.GetModelsDirectory(root, config, acceptUnsafe));
         }
 
         [TestCase("c:/path/to/root", "~/../../dir/models", false)]
@@ -44,7 +44,7 @@ namespace Umbraco.Tests.ModelsBuilder
         {
             Assert.Throws<ConfigurationErrorsException>(() =>
             {
-                var modelsDirectory = ModelsBuilderConfig.GetModelsDirectory(root, config, acceptUnsafe);
+                var modelsDirectory = ModelsBuilderConfigExtensions.GetModelsDirectory(root, config, acceptUnsafe);
             });
         }
     }