Fix RedirectResult for AspNetCore 2.2. Fixes #3986

Author: alrod

src/WebJobs.Script.WebHost/Middleware/FunctionInvocationMiddleware.cs

@@ -12,6 +12,7 @@
 using Microsoft.AspNetCore.Http;
 using Microsoft.AspNetCore.Http.Features;
 using Microsoft.AspNetCore.Mvc;
+using Microsoft.AspNetCore.Mvc.Abstractions;
 using Microsoft.AspNetCore.Routing;
 using Microsoft.Azure.WebJobs.Extensions.Http;
 using Microsoft.Azure.WebJobs.Logging;
@@ -62,11 +63,7 @@ public async Task Invoke(HttpContext context)
                     return;
                 }
 
-                var actionContext = new ActionContext
-                {
-                    HttpContext = context
-                };
-
+                ActionContext actionContext = new ActionContext(context, new RouteData(), new ActionDescriptor());
                 await result.ExecuteResultAsync(actionContext);
             }
         }

test/WebJobs.Script.Tests.Integration/TestScripts/CSharp/HttpTrigger-Redirect/function.json

@@ -0,0 +1,16 @@
+{
+    "bindings": [
+        {
+            "type": "httpTrigger",
+            "name": "req",
+            "direction": "in",
+            "methods": [ "get" ],
+            "authLevel": "anonymous"
+        },
+        {
+            "type": "http",
+            "name": "$return",
+            "direction": "out"
+        }
+    ]
+}

test/WebJobs.Script.Tests.Integration/TestScripts/CSharp/HttpTrigger-Redirect/run.csx

@@ -0,0 +1,11 @@
+#r "Newtonsoft.Json"
+
+using System.Net;
+using Microsoft.AspNetCore.Mvc;
+using Microsoft.Extensions.Primitives;
+using Newtonsoft.Json;
+
+public static async Task<IActionResult> Run(HttpRequest req, ILogger log)
+{
+    return new RedirectResult("http://bing.com");
+}

test/WebJobs.Script.Tests.Integration/WebHostEndToEnd/CSharpEndToEndTests.cs

@@ -150,6 +150,20 @@ public async Task VerifyHostHeader()
             Assert.Equal($"{actualProtocol}://{actualHost}/{path}", url);
         }
 
+        [Fact]
+        public async Task VerifyResultRedirect()
+        {
+            const string path = "api/httptrigger-redirect";
+            var request = new HttpRequestMessage
+            {
+                RequestUri = new Uri(string.Format($"http://localhost/{path}")),
+                Method = HttpMethod.Get
+            };
+
+            var response = await Fixture.Host.HttpClient.SendAsync(request);
+            Assert.Equal(response.StatusCode, HttpStatusCode.Redirect);
+        }
+
         [Fact]
         public async Task MultipleOutputs()
         {
@@ -406,6 +420,7 @@ public override void ConfigureJobHost(IWebJobsBuilder webJobsBuilder)
                         "AssembliesFromSharedLocation",
                         "HttpTrigger-Dynamic",
                         "HttpTrigger-Scenarios",
+                        "HttpTrigger-Redirect",
                         "HttpTriggerToBlob",
                         "FunctionExecutionContext",
                         "LoadScriptReference",