Expose extension methods to wrap and unwrap adapters

samples/CoreApp/SessionExampleExtensions.cs

@@ -54,7 +54,7 @@ static void SetValue(HttpContext context, byte[] data)
 
         builder.MapGet("/count", (HttpContextCore ctx) =>
         {
-            var context = (HttpContext)ctx;
+            var context = ctx.GetAdapter();
 
             if (context.Session!["callCount"] is not int count)
             {
@@ -69,7 +69,7 @@ static void SetValue(HttpContext context, byte[] data)
 
         builder.MapGet("/item", (HttpContextCore ctx) =>
         {
-            var context = (HttpContext)ctx;
+            var context = ctx.GetAdapter();
 
             var result = context.Session!["item"];
             context.Session!["item"] = default(int);

src/Microsoft.AspNetCore.SystemWebAdapters/Generated/ExcludedApis.txt

@@ -9,15 +9,13 @@ M:System.Web.HttpResponse.op_Implicit(Microsoft.AspNetCore.Http.HttpResponse)~Sy
 M:System.Web.HttpResponse.op_Implicit(System.Web.HttpResponse)~Microsoft.AspNetCore.Http.HttpResponse
 M:System.Web.HttpResponseBase.op_Implicit(Microsoft.AspNetCore.Http.HttpResponse)~System.Web.HttpResponseBase
 M:System.Web.HttpRequestBase.op_Implicit(Microsoft.AspNetCore.Http.HttpRequest)~System.Web.HttpRequestBase
+T:Microsoft.AspNetCore.SystemWebAdapters.SystemWebAdapterExtensions
 
 T:Microsoft.AspNetCore.SystemWebAdapters.SessionState.ISessionState
 
 # We manually type forward this only for .NET 4.7.2+
 T:System.Web.SameSiteMode
 
-T:Microsoft.AspNetCore.SystemWebAdapters.IBrowserCapabilitiesFactory
-T:Microsoft.AspNetCore.SystemWebAdapters.IHttpBrowserCapabilityFeature
-
 # We provide implementations of this on .NET Standard 2.0 and .NET 6.0
 T:System.Web.IHtmlString
 

src/Microsoft.AspNetCore.SystemWebAdapters/HttpContext.cs

@@ -2,6 +2,7 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 
 using System.Collections;
+using System.Collections.Generic;
 using System.Diagnostics.CodeAnalysis;
 using System.Linq;
 using System.Security.Principal;
@@ -11,6 +12,7 @@
 using Microsoft.AspNetCore.Http;
 using Microsoft.AspNetCore.Http.Features.Authentication;
 using Microsoft.AspNetCore.SystemWebAdapters;
+using Microsoft.AspNetCore.SystemWebAdapters.Internal;
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.Hosting;
 
@@ -38,7 +40,19 @@ internal HttpContext(HttpContextCore context)
 
     public HttpResponse Response => _response ??= new(_context.Response);
 
-    public IDictionary Items => _items ??= _context.Items.AsNonGeneric();
+    public IDictionary Items
+    {
+        get
+        {
+            if (_items is null)
+            {
+                var items = _context.Items;
+                _items = items is IDictionary d ? d : new NonGenericDictionaryWrapper(items);
+            }
+
+            return _items;
+        }
+    }
 
     public HttpServerUtility Server => _server ??= new(_context);
 

src/Microsoft.AspNetCore.SystemWebAdapters/Internal/NonGenericDictionaryWrapper.cs

@@ -36,7 +36,7 @@ public ICollection Keys
             {
                 if (_keys is null)
                 {
-                    _keys = _original.Keys.AsNonGeneric();
+                    _keys = AsNonGeneric(_original.Keys);
                 }
 
                 return _keys;
@@ -49,7 +49,7 @@ public ICollection Values
             {
                 if (_values is null)
                 {
-                    _values = _original.Values.AsNonGeneric();
+                    _values = AsNonGeneric(_original.Values);
                 }
 
                 return _values;
@@ -78,6 +78,9 @@ public void CopyTo(Array array, int index)
             }
         }
 
+        private static ICollection AsNonGeneric<T>(ICollection<T> collection)
+            => collection is ICollection c ? c : new NonGenericCollectionWrapper<T>(collection);
+
         public void Remove(object key) => _original.Remove(key);
 
         public IDictionaryEnumerator GetEnumerator() => new DictionaryEnumerator(_original);

src/Microsoft.AspNetCore.SystemWebAdapters/InternalSystemWebExtensions.cs → src/Microsoft.AspNetCore.SystemWebAdapters/SystemWebAdapterExtensions.cs

@@ -2,47 +2,38 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 
 using System;
-using System.Collections;
-using System.Collections.Generic;
 using System.Diagnostics.CodeAnalysis;
 using System.Web;
 using Microsoft.AspNetCore.Http.Features;
-using Microsoft.AspNetCore.SystemWebAdapters.Internal;
 
 namespace Microsoft.AspNetCore.SystemWebAdapters;
 
-internal static class InternalSystemWebExtensions
+public static class SystemWebAdapterExtensions
 {
     [return: NotNullIfNotNull(nameof(request))]
-    internal static HttpRequest? GetAdapter(this HttpRequestCore? request)
+    public static HttpRequest? GetAdapter(this HttpRequestCore? request)
         => request?.HttpContext.GetAdapter().Request;
 
     [return: NotNullIfNotNull(nameof(request))]
-    internal static HttpRequestBase? GetAdapterBase(this HttpRequestCore? request)
+    public static HttpRequestBase? GetAdapterBase(this HttpRequestCore? request)
         => request?.HttpContext.GetAdapterBase().Request;
 
     [return: NotNullIfNotNull(nameof(request))]
-    internal static HttpRequestCore? UnwrapAdapter(this HttpRequest? request) => request;
+    public static HttpRequestCore? UnwrapAdapter(this HttpRequest? request) => request;
 
     [return: NotNullIfNotNull(nameof(response))]
-    internal static HttpResponse? GetAdapter(this HttpResponseCore? response)
+    public static HttpResponse? GetAdapter(this HttpResponseCore? response)
         => response?.HttpContext.GetAdapter().Response;
 
-    [return: NotNullIfNotNull("request")]
-    internal static HttpResponseBase? GetAdapterBase(this HttpResponseCore? response)
+    [return: NotNullIfNotNull(nameof(response))]
+    public static HttpResponseBase? GetAdapterBase(this HttpResponseCore? response)
         => response?.HttpContext.GetAdapterBase().Response;
 
     [return: NotNullIfNotNull(nameof(response))]
-    internal static HttpResponseCore? UnwrapAdapter(this HttpResponse? response) => response;
-
-    internal static IDictionary AsNonGeneric(this IDictionary<object, object?> dictionary)
-         => dictionary is IDictionary d ? d : new NonGenericDictionaryWrapper(dictionary);
-
-    internal static ICollection AsNonGeneric<T>(this ICollection<T> collection)
-        => collection is ICollection c ? c : new NonGenericCollectionWrapper<T>(collection);
+    public static HttpResponseCore? UnwrapAdapter(this HttpResponse? response) => response;
 
     [return: NotNullIfNotNull(nameof(context))]
-    internal static HttpContext? GetAdapter(this HttpContextCore? context)
+    public static HttpContext? GetAdapter(this HttpContextCore? context)
     {
         if (context is null)
         {
@@ -61,10 +52,10 @@ internal static ICollection AsNonGeneric<T>(this ICollection<T> collection)
     }
 
     [return: NotNullIfNotNull(nameof(context))]
-    internal static HttpContextCore? UnwrapAdapter(this HttpContext? context) => context;
+    public static HttpContextCore? UnwrapAdapter(this HttpContext? context) => context;
 
     [return: NotNullIfNotNull(nameof(context))]
-    internal static HttpContextBase? GetAdapterBase(this HttpContextCore? context)
+    public static HttpContextBase? GetAdapterBase(this HttpContextCore? context)
     {
         if (context is null)
         {

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

@@ -21,7 +21,7 @@ public Task RequestInfo()
             Assert.Equal("/", context.Request.Path);
             Assert.Empty(context.Request.Query);
 
-            var adapter = (System.Web.HttpRequest)context.Request;
+            var adapter = context.Request.GetAdapter();
 
             Assert.Equal("", adapter.PathInfo);
             Assert.Equal("/", adapter.FilePath);
@@ -33,7 +33,7 @@ public Task RequestInfo()
     public Task RewriteRequestPath()
         => RunTest("/", context =>
         {
-            var adapter = (System.Web.HttpContext)context;
+            var adapter = context.GetAdapter();
 
             adapter.RewritePath("/some/path?q=1");
 
@@ -56,7 +56,7 @@ public Task RewriteRequestPath()
     public Task RewriteRequestPathInfo()
         => RunTest("/", context =>
         {
-            var adapter = (System.Web.HttpContext)context;
+            var adapter = context.GetAdapter();
 
             adapter.RewritePath("/some/path", "/pathInfo", "q=1");
 
@@ -79,7 +79,7 @@ public Task RewriteRequestPathInfo()
     public Task RewritePathViaCoreApis()
         => RunTest("/", context =>
         {
-            var adapter = (System.Web.HttpContext)context;
+            var adapter = context.GetAdapter();
 
             // This is the same as RewriteRequestPathInfo as above to get a custom PathInfo
             adapter.RewritePath("/some/path", "/pathInfo", "q=1");

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

@@ -2,8 +2,6 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 
 using System;
-using System.Net.Http;
-using System.Threading;
 using System.Threading.Tasks;
 using Microsoft.AspNetCore.Builder;
 using Microsoft.AspNetCore.Hosting;
@@ -46,7 +44,7 @@ public async Task BufferedOutputIsFlushedOnceWithStart()
         var result = await RunAsync(async context =>
         {
             context.Response.Write(ContentValue);
-            await ((HttpResponseCore)context.Response).StartAsync();
+            await context.Response.UnwrapAdapter().StartAsync();
         }, builder => builder.BufferResponseStream());
 
         Assert.Equal(ContentValue, result);
@@ -58,7 +56,7 @@ public async Task BufferedOutputIsFlushedOnceWithComplete()
         var result = await RunAsync(async context =>
         {
             context.Response.Write(ContentValue);
-            await ((HttpResponseCore)context.Response).CompleteAsync();
+            await context.Response.UnwrapAdapter().CompleteAsync();
         }, builder => builder.BufferResponseStream());
 
         Assert.Equal(ContentValue, result);