Porting SaveAS API to HttpPostedFile

src/Microsoft.AspNetCore.SystemWebAdapters/Generated/Ref.Standard.cs

@@ -208,6 +208,7 @@ public partial class HttpContextWrapper : System.Web.HttpContextBase
         public override System.Security.Principal.IPrincipal User { get { throw new System.PlatformNotSupportedException("Only supported when running on ASP.NET Core or System.Web");} set { throw new System.PlatformNotSupportedException("Only supported when running on ASP.NET Core or System.Web");} }
         public override void AddError(System.Exception ex) { throw new System.PlatformNotSupportedException("Only supported when running on ASP.NET Core or System.Web");}
         public override void ClearError() { throw new System.PlatformNotSupportedException("Only supported when running on ASP.NET Core or System.Web");}
+        public override object GetService(System.Type serviceType) { throw new System.PlatformNotSupportedException("Only supported when running on ASP.NET Core or System.Web");}
         public override void RewritePath(string path) { throw new System.PlatformNotSupportedException("Only supported when running on ASP.NET Core or System.Web");}
         public override void RewritePath(string path, bool rebaseClientPath) { throw new System.PlatformNotSupportedException("Only supported when running on ASP.NET Core or System.Web");}
         public override void RewritePath(string filePath, string pathInfo, string queryString) { throw new System.PlatformNotSupportedException("Only supported when running on ASP.NET Core or System.Web");}
@@ -313,6 +314,7 @@ internal HttpPostedFile() { }
         public string ContentType { get { throw new System.PlatformNotSupportedException("Only supported when running on ASP.NET Core or System.Web");} }
         public string FileName { get { throw new System.PlatformNotSupportedException("Only supported when running on ASP.NET Core or System.Web");} }
         public System.IO.Stream InputStream { get { throw new System.PlatformNotSupportedException("Only supported when running on ASP.NET Core or System.Web");} }
+        public void SaveAs(string filename) { throw new System.PlatformNotSupportedException("Only supported when running on ASP.NET Core or System.Web");}
     }
     public abstract partial class HttpPostedFileBase
     {

src/Microsoft.AspNetCore.SystemWebAdapters/HttpContext.cs

@@ -163,7 +163,7 @@ public void RewritePath(string filePath, string pathInfo, string? queryString, b
             return Server;
         }
 
-        return null;
+        return Context.RequestServices?.GetService(service);
     }
 
     public ISubscriptionToken DisposeOnPipelineCompleted(IDisposable target)

src/Microsoft.AspNetCore.SystemWebAdapters/HttpContextWrapper.cs

@@ -81,5 +81,7 @@ public override IPrincipal User
         public override void RewritePath(string filePath, string pathInfo, string? queryString, bool setClientFilePath) => _context.RewritePath(filePath, pathInfo, queryString, setClientFilePath);
 
         public override void SetSessionStateBehavior(SessionStateBehavior sessionStateBehavior) => _context.SetSessionStateBehavior(sessionStateBehavior);
+
+        public override object? GetService(Type serviceType) => ((IServiceProvider)_context).GetService(serviceType);
     }
 }

src/Microsoft.AspNetCore.SystemWebAdapters/HttpPostedFile.cs

@@ -1,6 +1,7 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
+using System.Globalization;
 using System.IO;
 using Microsoft.AspNetCore.Http;
 
@@ -19,4 +20,18 @@ public sealed class HttpPostedFile
     public int ContentLength => (int)File.Length;
 
     public Stream InputStream => File.OpenReadStream();
+
+    public void SaveAs(string filename)
+    {
+        if (!Path.IsPathRooted(filename))
+        {
+            throw new HttpException(string.Format(CultureInfo.InvariantCulture,
+                "The SaveAs method is configured to require a rooted path, and the path '{0}' is not rooted", filename));
+        }
+
+        using (var fileStream = new FileStream(filename, FileMode.Create))
+        {
+            InputStream.CopyTo(fileStream);
+        }
+    }
 }

test/Microsoft.AspNetCore.SystemWebAdapters.CoreServices.Tests/CacheTests.cs

@@ -32,6 +32,10 @@ public void CacheFromHttpContext()
 
             // Assert
             Assert.Same(cache, result);
+
+            //Act via GetService
+            var cacheFromService = context.GetService<Cache>();
+            Assert.Same(cache, cacheFromService);
         }
 
         [Fact]
@@ -54,6 +58,10 @@ public void CacheFromHttpContextWrapper()
 
             // Assert
             Assert.Same(cache, result);
+
+            //Act via GetService
+            var cacheFromService = contextWrapper.GetService<Cache>();
+            Assert.Same(cache, cacheFromService);
         }
     }
 }

test/Microsoft.AspNetCore.SystemWebAdapters.Tests/HttpContextTests.cs

@@ -12,6 +12,7 @@
 using Microsoft.AspNetCore.Http;
 using Microsoft.AspNetCore.SystemWebAdapters.Features;
 using Microsoft.AspNetCore.SystemWebAdapters.SessionState;
+using Microsoft.Extensions.DependencyInjection;
 using Moq;
 using Xunit;
 
@@ -152,8 +153,8 @@ public void GetServiceReturnsExpected()
             Assert.Same(context.Response, provider.GetService(typeof(HttpResponse)));
             Assert.Same(context.Server, provider.GetService(typeof(HttpServerUtility)));
             Assert.Same(context.Session, provider.GetService(typeof(HttpSessionState)));
-
             Assert.Null(provider.GetService(typeof(HttpContext)));
+            Assert.Null(provider.GetService<Cache>());
         }
 
         [Fact]
@@ -215,6 +216,10 @@ public void CacheFromServices()
 
             // Assert
             Assert.Same(cache, result);
+
+            var provider = (IServiceProvider)context;
+            Assert.NotNull(provider.GetService<Cache>());
+            Assert.Same(cache, provider.GetService<Cache>());
         }
 
         [Fact]

test/Microsoft.AspNetCore.SystemWebAdapters.Tests/HttpPostedFileTests.cs

@@ -1,6 +1,8 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
+using System;
+using System.Globalization;
 using System.IO;
 using System.Web;
 using AutoFixture;
@@ -100,4 +102,37 @@ public void InputStream()
         // Assert
         Assert.Equal(expected.Object, stream);
     }
+
+    [Fact]
+    public void SaveAsForInvalidRootPath()
+    {
+        // Arrange
+        var file = new Mock<IFormFile>();
+        var expectedStream = new Mock<Stream>();
+        file.Setup(f => f.OpenReadStream()).Returns(expectedStream.Object);
+        var posted = new HttpPostedFile(file.Object);
+
+        //Act and Assert
+        Assert.Throws<HttpException>(() => posted.SaveAs("InvalidPath"));
+    }
+
+    [Fact]
+    public void SaveAsWithValidRootPath()
+    {
+        // Arrange
+        var file = new Mock<IFormFile>();
+        var expectedStream = new Mock<Stream>();
+        file.Setup(f => f.OpenReadStream()).Returns(expectedStream.Object);
+        string validTempPath = string.Format(CultureInfo.InvariantCulture, @"{0}{1}.txt", Path.GetTempPath(), Guid.NewGuid());
+        var posted = new HttpPostedFile(file.Object);
+
+        //Act
+        posted.SaveAs(validTempPath);
+
+        //Assert
+        Assert.True(File.Exists(validTempPath), "Temp file should be created");
+
+        //Cleanup
+        File.Delete(validTempPath);
+    }
 }