Use AssemblyLoadContext to load EFC.Design

Fixes #35265

src/EFCore.Tasks/Tasks/Internal/OperationTaskBase.cs

@@ -30,6 +30,11 @@ public abstract class OperationTaskBase : ToolTask
     /// </summary>
     public ITaskItem? StartupAssembly { get; set; }
 
+    /// <summary>
+    ///     The location of Microsoft.EntityFrameworkCore.Design.dll
+    /// </summary>
+    public ITaskItem? DesignAssembly { get; set; }
+
     /// <summary>
     ///     The target framework moniker.
     /// </summary>
@@ -188,13 +193,17 @@ protected override string GenerateCommandLineCommands()
             args.Add(runtimeFrameworkVersion);
         }
 
+#if !NET10_0
+#elif NET472
+#error Target framework needs to be updated here
+#endif
         args.Add(
             Path.Combine(
                 Path.GetDirectoryName(typeof(OperationTaskBase).Assembly.Location)!,
                 "..",
                 "..",
                 "tools",
-                "netcoreapp2.0",
+                "net10.0",
                 "ef.dll"));
 
         args.AddRange(AdditionalArguments);
@@ -207,6 +216,12 @@ protected override string GenerateCommandLineCommands()
             args.Add(Path.ChangeExtension(StartupAssembly.ItemSpec, ".dll"));
         }
 
+        if (DesignAssembly != null)
+        {
+            args.Add("--design-assembly");
+            args.Add(DesignAssembly.ItemSpec);
+        }
+
         if (Project != null)
         {
             args.Add("--project");

src/EFCore.Tasks/buildTransitive/Microsoft.EntityFrameworkCore.Tasks.targets

@@ -76,7 +76,7 @@ For Publish:
              Properties="Configuration=$(Configuration);Platform=$(Platform);_EFGenerationStage=$(_EFGenerationStage)" />
   </Target>
 
-  <Target Name="OptimizeDbContext">
+  <Target Name="OptimizeDbContext" DependsOnTargets="ResolvePackageAssets">
     <PropertyGroup>
       <EFRootNamespace Condition="'$(EFRootNamespace)'==''">$(RootNamespace)</EFRootNamespace>
       <EFRootNamespace Condition="'$(EFRootNamespace)'==''">$(AssemblyName)</EFRootNamespace>
@@ -90,9 +90,14 @@ For Publish:
       <EFNullable Condition="'$(EFNullable)'==''">false</EFNullable>
     </PropertyGroup>
 
+    <ItemGroup>
+      <DesignAssembly Include="@(RuntimeCopyLocalItems)" Condition="$([System.String]::Copy('%(FullPath)').EndsWith('Microsoft.EntityFrameworkCore.Design.dll'))" />
+    </ItemGroup>
+
     <OptimizeDbContext Assembly="$(_AssemblyFullName)"
                        StartupAssembly="$(EFStartupAssembly)"
                        ProjectAssetsFile="$(ProjectAssetsFile)"
+                       DesignAssembly="@(DesignAssembly->'%(FullPath)')"
                        RuntimeFrameworkVersion="$(RuntimeFrameworkVersion)"
                        TargetFrameworkMoniker="$(TargetFrameworkMoniker)"
                        DbContextType="$(DbContextType)"

src/EFCore.Tools/tools/EntityFrameworkCore.psm1

@@ -1329,6 +1329,15 @@ function EF($project, $startupProject, $params, $applicationArgs, [switch] $skip
         $params += '--nullable'
     }
 
+    # NB: -join is here to support ConvertFrom-Json on PowerShell 3.0
+    $references = (dotnet build $startupProject.FullName /t:ResolvePackageAssets /getItem:RuntimeCopyLocalItems) -join "`n" | ConvertFrom-Json
+
+    $designReference = $references.Items.RuntimeCopyLocalItems | ? { $_.FullPath.EndsWith('Microsoft.EntityFrameworkCore.Design.dll') }
+    if ($designReference -ne $null)
+    {
+        $params += '--design-assembly', $designReference.FullPath
+    }
+
     $arguments = ToArguments $params
     if ($applicationArgs)
     {

src/dotnet-ef/Project.cs

@@ -29,6 +29,7 @@ public Project(string file, string? framework, string? configuration, string? ru
     public string ProjectName { get; }
 
     public string? AssemblyName { get; set; }
+    public string? DesignAssembly { get; set; }
     public string? Language { get; set; }
     public string? OutputPath { get; set; }
     public string? PlatformTarget { get; set; }
@@ -50,78 +51,84 @@ public static Project FromFile(
     {
         Debug.Assert(!string.IsNullOrEmpty(file), "file is null or empty.");
 
-        IDictionary<string, string> metadata;
-        var metadataFile = Path.GetTempFileName();
-        try
-        {
-            var args = new List<string>
+        var args = new List<string>
             {
                 "msbuild",
             };
 
-            if (framework != null)
-            {
-                args.Add($"/property:TargetFramework={framework}");
-            }
+        if (framework != null)
+        {
+            args.Add($"/property:TargetFramework={framework}");
+        }
 
-            if (configuration != null)
-            {
-                args.Add($"/property:Configuration={configuration}");
-            }
+        if (configuration != null)
+        {
+            args.Add($"/property:Configuration={configuration}");
+        }
 
-            if (runtime != null)
-            {
-                args.Add($"/property:RuntimeIdentifier={runtime}");
-            }
+        if (runtime != null)
+        {
+            args.Add($"/property:RuntimeIdentifier={runtime}");
+        }
 
-            foreach (var property in typeof(Project).GetProperties())
-            {
-                args.Add($"/getProperty:{property.Name}");
-            }
+        foreach (var property in typeof(Project).GetProperties())
+        {
+            args.Add($"/getProperty:{property.Name}");
+        }
 
-            args.Add("/getProperty:Platform");
+        args.Add("/getProperty:Platform");
 
-            args.Add(file);
+        args.Add("/t:ResolvePackageAssets");
+        args.Add("/getItem:RuntimeCopyLocalItems");
 
-            var output = new StringBuilder();
+        args.Add(file);
 
-            var exitCode = Exe.Run("dotnet", args, handleOutput: line => output.AppendLine(line));
-            if (exitCode != 0)
-            {
-                throw new CommandException(Resources.GetMetadataFailed);
-            }
+        var output = new StringBuilder();
 
-            metadata = JsonSerializer.Deserialize<Dictionary<string, Dictionary<string, string>>>(output.ToString())!["Properties"];
-        }
-        finally
+        var exitCode = Exe.Run("dotnet", args, handleOutput: line => output.AppendLine(line));
+        if (exitCode != 0)
         {
-            File.Delete(metadataFile);
+            throw new CommandException(Resources.GetMetadataFailed);
         }
 
-        var platformTarget = metadata[nameof(PlatformTarget)];
+        var metadata = JsonSerializer.Deserialize<ProjectMetadata>(output.ToString())!;
+
+        var designAssembly = metadata.Items["RuntimeCopyLocalItems"]
+            .Select(i => i["FullPath"])
+            .FirstOrDefault(i => i.Contains("Microsoft.EntityFrameworkCore.Design", StringComparison.InvariantCulture));
+        var properties = metadata.Properties;
+
+        var platformTarget = properties[nameof(PlatformTarget)];
         if (platformTarget.Length == 0)
         {
-            platformTarget = metadata["Platform"];
+            platformTarget = properties["Platform"];
         }
 
         return new Project(file, framework, configuration, runtime)
         {
-            AssemblyName = metadata[nameof(AssemblyName)],
-            Language = metadata[nameof(Language)],
-            OutputPath = metadata[nameof(OutputPath)],
+            AssemblyName = properties[nameof(AssemblyName)],
+            DesignAssembly = designAssembly,
+            Language = properties[nameof(Language)],
+            OutputPath = properties[nameof(OutputPath)],
             PlatformTarget = platformTarget,
-            ProjectAssetsFile = metadata[nameof(ProjectAssetsFile)],
-            ProjectDir = metadata[nameof(ProjectDir)],
-            RootNamespace = metadata[nameof(RootNamespace)],
-            RuntimeFrameworkVersion = metadata[nameof(RuntimeFrameworkVersion)],
-            TargetFileName = metadata[nameof(TargetFileName)],
-            TargetFrameworkMoniker = metadata[nameof(TargetFrameworkMoniker)],
-            Nullable = metadata[nameof(Nullable)],
-            TargetFramework = metadata[nameof(TargetFramework)],
-            TargetPlatformIdentifier = metadata[nameof(TargetPlatformIdentifier)]
+            ProjectAssetsFile = properties[nameof(ProjectAssetsFile)],
+            ProjectDir = properties[nameof(ProjectDir)],
+            RootNamespace = properties[nameof(RootNamespace)],
+            RuntimeFrameworkVersion = properties[nameof(RuntimeFrameworkVersion)],
+            TargetFileName = properties[nameof(TargetFileName)],
+            TargetFrameworkMoniker = properties[nameof(TargetFrameworkMoniker)],
+            Nullable = properties[nameof(Nullable)],
+            TargetFramework = properties[nameof(TargetFramework)],
+            TargetPlatformIdentifier = properties[nameof(TargetPlatformIdentifier)]
         };
     }
 
+    private record class ProjectMetadata
+    {
+        public Dictionary<string, string> Properties { get; set; } = null!;
+        public Dictionary<string, Dictionary<string, string>[]> Items { get; set; } = null!;
+    }
+
     public void Build(IEnumerable<string>? additionalArgs)
     {
         var args = new List<string> { "build" };

src/dotnet-ef/RootCommand.cs

@@ -200,6 +200,13 @@ protected override int Execute(string[] _)
         args.Add("--framework");
         args.Add(startupProject.TargetFramework!);
 
+        var designAssembly = startupProject.DesignAssembly;
+        if (!string.IsNullOrEmpty(designAssembly))
+        {
+            args.Add("--design-assembly");
+            args.Add(designAssembly);
+        }
+
         if (_configuration.HasValue())
         {
             args.Add("--configuration");

src/ef/Commands/ProjectCommandBase.cs

@@ -6,8 +6,9 @@
 using Microsoft.EntityFrameworkCore.Design;
 using Microsoft.EntityFrameworkCore.Tools.Properties;
 #if NET472
-using System;
 using System.Configuration;
+#else
+using System.Runtime.Loader;
 #endif
 
 namespace Microsoft.EntityFrameworkCore.Tools.Commands
@@ -20,6 +21,7 @@ internal abstract class ProjectCommandBase : EFCommandBase
         private CommandOption? _language;
         private CommandOption? _nullable;
         private string? _efcoreVersion;
+        private CommandOption? _designAssembly;
 
         protected CommandOption? Assembly { get; private set; }
         protected CommandOption? Project { get; private set; }
@@ -29,10 +31,61 @@ internal abstract class ProjectCommandBase : EFCommandBase
         protected CommandOption? Framework { get; private set; }
         protected CommandOption? Configuration { get; private set; }
 
+#if !NET472
+        private AssemblyLoadContext? _assemblyLoadContext;
+        protected AssemblyLoadContext AssemblyLoadContext
+        {
+            get
+            {
+                if (_assemblyLoadContext != null)
+                {
+                    return _assemblyLoadContext;
+                }
+
+                if (_designAssembly!.Value() != null)
+                {
+                    AssemblyLoadContext.Default.Resolving += (context, name) =>
+                    {
+                        var assemblyPath = Path.GetDirectoryName(_designAssembly!.Value())!;
+                        assemblyPath = Path.Combine(assemblyPath, name.Name + ".dll");
+                        return File.Exists(assemblyPath) ? context.LoadFromAssemblyPath(assemblyPath) : null;
+                    };
+                    _assemblyLoadContext = AssemblyLoadContext.Default;
+                }
+
+                return AssemblyLoadContext.Default;
+            }
+        }
+#endif
+
         protected string? EFCoreVersion
-            => _efcoreVersion ??= System.Reflection.Assembly.Load("Microsoft.EntityFrameworkCore.Design")
-                .GetCustomAttribute<AssemblyInformationalVersionAttribute>()
-                ?.InformationalVersion;
+        {
+            get
+            {
+                if (_efcoreVersion != null)
+                {
+                    return _efcoreVersion;
+                }
+
+                Assembly? assembly = null;
+#if !NET472
+                assembly = AssemblyLoadContext.LoadFromAssemblyName(new AssemblyName("Microsoft.EntityFrameworkCore.Design"));
+#else
+                if (_designAssembly!.Value() != null)
+                {
+                    var assemblyPath = Path.GetDirectoryName(_designAssembly!.Value());
+                    assemblyPath = Path.Combine(assemblyPath, "Microsoft.EntityFrameworkCore.Design.dll");
+                    assembly = System.Reflection.Assembly.LoadFrom(assemblyPath);
+                } else
+                {
+                    assembly = System.Reflection.Assembly.Load("Microsoft.EntityFrameworkCore.Design");
+                }
+#endif
+                _efcoreVersion = assembly.GetCustomAttribute<AssemblyInformationalVersionAttribute>()
+                        ?.InformationalVersion;
+                return _efcoreVersion;
+            }
+        }
 
         public override void Configure(CommandLineApplication command)
         {
@@ -50,6 +103,7 @@ public override void Configure(CommandLineApplication command)
             WorkingDir = command.Option("--working-dir <PATH>", Resources.WorkingDirDescription);
             Framework = command.Option("--framework <FRAMEWORK>", Resources.FrameworkDescription);
             Configuration = command.Option("--configuration <CONFIGURATION>", Resources.ConfigurationDescription);
+            _designAssembly = command.Option("--design-assembly <PATH>", Resources.DesignAssemblyDescription);
 
             base.Configure(command);
         }

src/ef/Properties/Resources.resx

@@ -210,6 +210,9 @@
   <data name="DbContextType" xml:space="preserve">
     <value>Type: {type}</value>
   </data>
+  <data name="DesignAssemblyDescription" xml:space="preserve">
+    <value>The location of the referenced Microsoft.EntityFrameworkCore.Design assembly.</value>
+  </data>
   <data name="DesignNotFound" xml:space="preserve">
     <value>Your startup project '{startupProject}' doesn't reference Microsoft.EntityFrameworkCore.Design. This package is required for the Entity Framework Core Tools to work. Ensure your startup project is correct, install the package, and try again.</value>
   </data>