Feature/proxy reason phrase (#618)

* #599 started work to proxy reason phrase

* #599 test for aggregator

src/Ocelot/Cache/CachedResponse.cs

@@ -1,30 +1,33 @@
-using System.Collections.Generic;
-using System.Net;
-
-namespace Ocelot.Cache
-{
-    public class CachedResponse
-    {
-        public CachedResponse(
-            HttpStatusCode statusCode,
-            Dictionary<string, IEnumerable<string>> headers,
-            string body,
-            Dictionary<string, IEnumerable<string>> contentHeaders
-
-            )
-        {
-            StatusCode = statusCode;
-            Headers = headers ?? new Dictionary<string, IEnumerable<string>>();
-            ContentHeaders = contentHeaders ?? new Dictionary<string, IEnumerable<string>>();
-            Body = body ?? "";
-        }
-
-        public HttpStatusCode StatusCode { get; private set; }
-
-        public Dictionary<string, IEnumerable<string>> Headers { get; private set; }
-
-        public Dictionary<string, IEnumerable<string>> ContentHeaders { get; private set; }
-
-        public string Body { get; private set; }
-    }
-}
+using System.Collections.Generic;
+using System.Net;
+
+namespace Ocelot.Cache
+{
+    public class CachedResponse
+    {
+        public CachedResponse(
+            HttpStatusCode statusCode,
+            Dictionary<string, IEnumerable<string>> headers,
+            string body,
+            Dictionary<string, IEnumerable<string>> contentHeaders,
+            string reasonPhrase
+            )
+        {
+            StatusCode = statusCode;
+            Headers = headers ?? new Dictionary<string, IEnumerable<string>>();
+            ContentHeaders = contentHeaders ?? new Dictionary<string, IEnumerable<string>>();
+            Body = body ?? "";
+            ReasonPhrase = reasonPhrase;
+        }
+
+        public HttpStatusCode StatusCode { get; private set; }
+
+        public Dictionary<string, IEnumerable<string>> Headers { get; private set; }
+
+        public Dictionary<string, IEnumerable<string>> ContentHeaders { get; private set; }
+
+        public string Body { get; private set; }
+        
+        public string ReasonPhrase { get; private set; }
+    }
+}

src/Ocelot/Cache/Middleware/OutputCacheMiddleware.cs

@@ -87,7 +87,7 @@
                 streamContent.Headers.TryAddWithoutValidation(header.Key, header.Value);
             }
 
-            return new DownstreamResponse(streamContent, cached.StatusCode, cached.Headers.ToList());
+            return new DownstreamResponse(streamContent, cached.StatusCode, cached.Headers.ToList(), cached.ReasonPhrase);
         }
 
         internal async Task<CachedResponse> CreateCachedResponse(DownstreamResponse response)
@@ -109,7 +109,7 @@
 
             var contentHeaders = response?.Content?.Headers.ToDictionary(v => v.Key, v => v.Value);
 
-            var cached = new CachedResponse(statusCode, headers, body, contentHeaders);
+            var cached = new CachedResponse(statusCode, headers, body, contentHeaders, response.ReasonPhrase);
             return cached;
         }
     }

src/Ocelot/Middleware/DownstreamResponse.cs

@@ -7,25 +7,27 @@ namespace Ocelot.Middleware
 {
     public class DownstreamResponse
     {
-        public DownstreamResponse(HttpContent content, HttpStatusCode statusCode, List<Header> headers)
+        public DownstreamResponse(HttpContent content, HttpStatusCode statusCode, List<Header> headers, string reasonPhrase)
         {
             Content = content;
             StatusCode = statusCode;
             Headers = headers ?? new List<Header>();
+            ReasonPhrase = reasonPhrase;
         }
 
         public DownstreamResponse(HttpResponseMessage response)
-            :this(response.Content, response.StatusCode, response.Headers.Select(x => new Header(x.Key, x.Value)).ToList())
+            :this(response.Content, response.StatusCode, response.Headers.Select(x => new Header(x.Key, x.Value)).ToList(), response.ReasonPhrase)
         {
         }
 
-        public DownstreamResponse(HttpContent content, HttpStatusCode statusCode, IEnumerable<KeyValuePair<string, IEnumerable<string>>> headers)
-            :this(content, statusCode, headers.Select(x => new Header(x.Key, x.Value)).ToList())
+        public DownstreamResponse(HttpContent content, HttpStatusCode statusCode, IEnumerable<KeyValuePair<string, IEnumerable<string>>> headers, string reasonPhrase)
+            :this(content, statusCode, headers.Select(x => new Header(x.Key, x.Value)).ToList(), reasonPhrase)
         {
         }
 
         public HttpContent Content { get; }
         public HttpStatusCode StatusCode { get; }
         public List<Header> Headers { get; }
+        public string ReasonPhrase {get;}
     }
 }

src/Ocelot/Middleware/Multiplexer/SimpleJsonResponseAggregator.cs

@@ -46,7 +46,7 @@ namespace Ocelot.Middleware.Multiplexer
                 Headers = {ContentType = new MediaTypeHeaderValue("application/json")}
             };
 
-            originalContext.DownstreamResponse = new DownstreamResponse(stringContent, HttpStatusCode.OK, new List<KeyValuePair<string, IEnumerable<string>>>());
+            originalContext.DownstreamResponse = new DownstreamResponse(stringContent, HttpStatusCode.OK, new List<KeyValuePair<string, IEnumerable<string>>>(), "cannot return from aggregate..which reason phrase would you use?");
         }
 
         private static void MapAggregateError(DownstreamContext originalContext, List<DownstreamContext> downstreamContexts, int i)

src/Ocelot/Responder/HttpContextResponder.cs

@@ -3,6 +3,7 @@ using System.Linq;
 using System.Net;
 using System.Threading.Tasks;
 using Microsoft.AspNetCore.Http;
+using Microsoft.AspNetCore.Http.Features;
 using Microsoft.Extensions.Primitives;
 using Ocelot.Headers;
 using Ocelot.Middleware;
@@ -45,6 +46,8 @@ namespace Ocelot.Responder
 
             context.Response.StatusCode = (int)response.StatusCode;
 
+            context.Response.HttpContext.Features.Get<IHttpResponseFeature>().ReasonPhrase = response.ReasonPhrase;
+
             using(content)
             {
                 if (response.StatusCode != HttpStatusCode.NotModified && context.Response.ContentLength != 0)

test/Ocelot.AcceptanceTests/AggregateTests.cs

@@ -559,7 +559,7 @@ namespace Ocelot.AcceptanceTests
             var merge = $"{one}, {two}";
             merge = merge.Replace("Hello", "Bye").Replace("{", "").Replace("}", "");
             var headers = responses.SelectMany(x => x.Headers).ToList();
-            return new DownstreamResponse(new StringContent(merge), HttpStatusCode.OK, headers);
+            return new DownstreamResponse(new StringContent(merge), HttpStatusCode.OK, headers, "some reason");
         }
     }
 }

test/Ocelot.AcceptanceTests/ReasonPhraseTests.cs

@@ -0,0 +1,76 @@
+namespace Ocelot.AcceptanceTests
+{
+    using System;
+    using System.Collections.Generic;
+    using System.Net;
+    using Microsoft.AspNetCore.Http;
+    using Microsoft.AspNetCore.Http.Features;
+    using Ocelot.Configuration.File;
+    using Shouldly;
+    using TestStack.BDDfy;
+    using Xunit;
+
+    public class ReasonPhraseTests : IDisposable
+    {
+        private readonly Steps _steps;
+        private string _contentType;
+        private long? _contentLength;
+        private bool _contentTypeHeaderExists;
+        private readonly ServiceHandler _serviceHandler;
+
+        public ReasonPhraseTests()
+        {
+            _serviceHandler = new ServiceHandler();
+            _steps = new Steps();
+        }
+
+        [Fact]
+        public void should_return_reason_phrase()
+        {
+            var configuration = new FileConfiguration
+            {
+                ReRoutes = new List<FileReRoute>
+                    {
+                        new FileReRoute
+                        {
+                            DownstreamPathTemplate = "/",
+                            DownstreamScheme = "http",
+                            DownstreamHostAndPorts = new List<FileHostAndPort>
+                            {
+                                new FileHostAndPort
+                                {
+                                    Host = "localhost",
+                                    Port = 51339,
+                                }
+                            },
+                            UpstreamPathTemplate = "/",
+                            UpstreamHttpMethod = new List<string> { "Get" },
+                        }
+                    }
+            };
+
+            this.Given(x => x.GivenThereIsAServiceRunningOn("http://localhost:51339", "/", "some reason"))
+                .And(x => _steps.GivenThereIsAConfiguration(configuration))
+                .And(x => _steps.GivenOcelotIsRunning())
+                .When(x => _steps.WhenIGetUrlOnTheApiGateway("/"))
+                .And(_ => _steps.ThenTheReasonPhraseIs("some reason"))
+                .BDDfy();
+        }
+
+        private void GivenThereIsAServiceRunningOn(string baseUrl, string basePath, string reasonPhrase)
+        {
+            _serviceHandler.GivenThereIsAServiceRunningOn(baseUrl, basePath, async context =>
+            {
+                context.Response.HttpContext.Features.Get<IHttpResponseFeature>().ReasonPhrase = reasonPhrase;
+
+                await context.Response.WriteAsync("YOYO!");
+            });
+        }
+
+        public void Dispose()
+        {
+            _serviceHandler?.Dispose();
+            _steps.Dispose();
+        }
+    }
+}

test/Ocelot.AcceptanceTests/Steps.cs

@@ -452,6 +452,11 @@
             header.First().ShouldBe(value);
         }
 
+        public void ThenTheReasonPhraseIs(string expected)
+        {
+            _response.ReasonPhrase.ShouldBe(expected);
+        }
+
         /// <summary>
         /// This is annoying cos it should be in the constructor but we need to set up the file before calling startup so its a step.
         /// </summary>

test/Ocelot.UnitTests/Cache/OutputCacheMiddlewareTests.cs

@@ -53,7 +53,7 @@
                 { "content-type", new List<string> { "application/json" } }
             };
 
-            var cachedResponse = new CachedResponse(HttpStatusCode.OK, headers, "", contentHeaders);
+            var cachedResponse = new CachedResponse(HttpStatusCode.OK, headers, "", contentHeaders, "some reason");
             this.Given(x => x.GivenThereIsACachedResponse(cachedResponse))
                 .And(x => x.GivenTheDownstreamRouteIs())
                 .When(x => x.WhenICallTheMiddleware())
@@ -69,7 +69,7 @@
                 { "Expires", new List<string> { "-1" } }
             };
 
-            var cachedResponse = new CachedResponse(HttpStatusCode.OK, new Dictionary<string, IEnumerable<string>>(), "", contentHeaders);
+            var cachedResponse = new CachedResponse(HttpStatusCode.OK, new Dictionary<string, IEnumerable<string>>(), "", contentHeaders, "some reason");
             this.Given(x => x.GivenThereIsACachedResponse(cachedResponse))
                 .And(x => x.GivenTheDownstreamRouteIs())
                 .When(x => x.WhenICallTheMiddleware())

test/Ocelot.UnitTests/Headers/HttpResponseHeaderReplacerTests.cs

@@ -1,283 +1,283 @@
-using Xunit;
-using Shouldly;
-using TestStack.BDDfy;
-using System.Net.Http;
-using Ocelot.Headers;
-using Ocelot.Configuration;
-using System.Collections.Generic;
-using Ocelot.Responses;
-using System.Linq;
-using System.Net;
-using Moq;
-using Ocelot.Infrastructure;
-using Ocelot.Middleware;
-using Ocelot.Infrastructure.RequestData;
-using Ocelot.Middleware.Multiplexer;
-using Ocelot.Request.Middleware;
-
-namespace Ocelot.UnitTests.Headers
-{
-    public class HttpResponseHeaderReplacerTests
-    {
-        private DownstreamResponse _response;
-        private Placeholders _placeholders;
-        private readonly HttpResponseHeaderReplacer _replacer;
-        private List<HeaderFindAndReplace> _headerFindAndReplaces;
-        private Response _result;
-        private DownstreamRequest _request;
-        private Mock<IBaseUrlFinder> _finder;
-        private Mock<IRequestScopedDataRepository> _repo;
-
-        public HttpResponseHeaderReplacerTests()
-        {
-            _repo = new Mock<IRequestScopedDataRepository>();
-            _finder = new Mock<IBaseUrlFinder>();
-            _placeholders = new Placeholders(_finder.Object, _repo.Object);
-            _replacer = new HttpResponseHeaderReplacer(_placeholders);
-        }
-
-        [Fact]
-        public void should_replace_headers()
-        {
-            var response = new DownstreamResponse(new StringContent(string.Empty), HttpStatusCode.Accepted,
-                new List<KeyValuePair<string, IEnumerable<string>>>()
-                {
-                    new KeyValuePair<string, IEnumerable<string>>("test", new List<string> {"test"})
-                });
-
-            var fAndRs = new List<HeaderFindAndReplace> {new HeaderFindAndReplace("test", "test", "chiken", 0)};
-
-            this.Given(x => GivenTheHttpResponse(response))
-                .And(x => GivenTheFollowingHeaderReplacements(fAndRs))
-                .When(x => WhenICallTheReplacer())
-                .Then(x => ThenTheHeadersAreReplaced())
-                .BDDfy();
-        }
-
-        [Fact]
-        public void should_not_replace_headers()
-        {
-            var response = new DownstreamResponse(new StringContent(string.Empty), HttpStatusCode.Accepted,
-                new List<KeyValuePair<string, IEnumerable<string>>>()
-                {
-                    new KeyValuePair<string, IEnumerable<string>>("test", new List<string> {"test"})
-                });
-
-            var fAndRs = new List<HeaderFindAndReplace>();
-
-            this.Given(x => GivenTheHttpResponse(response))
-                .And(x => GivenTheFollowingHeaderReplacements(fAndRs))
-                .When(x => WhenICallTheReplacer())
-                .Then(x => ThenTheHeadersAreNotReplaced())
-                .BDDfy();
-        }
-
-        [Fact]
-        public void should_replace_downstream_base_url_with_ocelot_base_url()
-        {
-            const string downstreamUrl = "http://downstream.com/";
-
-            var request =
-                new HttpRequestMessage(HttpMethod.Get, "http://test.com") {RequestUri = new System.Uri(downstreamUrl)};
-
-            var response = new DownstreamResponse(new StringContent(string.Empty), HttpStatusCode.Accepted,
-                new List<KeyValuePair<string, IEnumerable<string>>>()
-                {
-                    new KeyValuePair<string, IEnumerable<string>>("Location", new List<string> {downstreamUrl})
-                });
-
-            var fAndRs = new List<HeaderFindAndReplace>
-            {
-                new HeaderFindAndReplace("Location", "{DownstreamBaseUrl}", "http://ocelot.com/", 0)
-            };
-
-            this.Given(x => GivenTheHttpResponse(response))
-                .And(x => GivenTheRequestIs(request))
-                .And(x => GivenTheFollowingHeaderReplacements(fAndRs))
-                .When(x => WhenICallTheReplacer())
-                .Then(x => ThenTheHeaderShouldBe("Location", "http://ocelot.com/"))
-                .BDDfy();
-        }
-
-        [Fact]
-        public void should_replace_downstream_base_url_with_ocelot_base_url_with_port()
-        {
-            const string downstreamUrl = "http://downstream.com/";
-
-            var request =
-                new HttpRequestMessage(HttpMethod.Get, "http://test.com") {RequestUri = new System.Uri(downstreamUrl)};
-
-            var response = new DownstreamResponse(new StringContent(string.Empty), HttpStatusCode.Accepted,
-                new List<KeyValuePair<string, IEnumerable<string>>>()
-                {
-                    new KeyValuePair<string, IEnumerable<string>>("Location", new List<string> {downstreamUrl})
-                });
-
-            var fAndRs = new List<HeaderFindAndReplace>
-            {
-                new HeaderFindAndReplace("Location", "{DownstreamBaseUrl}", "http://ocelot.com:123/", 0)
-            };
-
-            this.Given(x => GivenTheHttpResponse(response))
-                .And(x => GivenTheRequestIs(request))
-                .And(x => GivenTheFollowingHeaderReplacements(fAndRs))
-                .When(x => WhenICallTheReplacer())
-                .Then(x => ThenTheHeaderShouldBe("Location", "http://ocelot.com:123/"))
-                .BDDfy();
-        }
-
-        [Fact]
-        public void should_replace_downstream_base_url_with_ocelot_base_url_and_path()
-        {
-            const string downstreamUrl = "http://downstream.com/test/product";
-
-            var request =
-                new HttpRequestMessage(HttpMethod.Get, "http://test.com") {RequestUri = new System.Uri(downstreamUrl)};
-
-            var response = new DownstreamResponse(new StringContent(string.Empty), HttpStatusCode.Accepted,
-                new List<KeyValuePair<string, IEnumerable<string>>>()
-                {
-                    new KeyValuePair<string, IEnumerable<string>>("Location", new List<string> {downstreamUrl})
-                });
-
-            var fAndRs = new List<HeaderFindAndReplace>
-            {
-                new HeaderFindAndReplace("Location", "{DownstreamBaseUrl}", "http://ocelot.com/", 0)
-            };
-
-            this.Given(x => GivenTheHttpResponse(response))
-                .And(x => GivenTheRequestIs(request))
-                .And(x => GivenTheFollowingHeaderReplacements(fAndRs))
-                .When(x => WhenICallTheReplacer())
-                .Then(x => ThenTheHeaderShouldBe("Location", "http://ocelot.com/test/product"))
-                .BDDfy();
-        }
-
-        [Fact]
-        public void should_replace_downstream_base_url_with_ocelot_base_url_with_path_and_port()
-        {
-            const string downstreamUrl = "http://downstream.com/test/product";
-
-            var request =
-                new HttpRequestMessage(HttpMethod.Get, "http://test.com") {RequestUri = new System.Uri(downstreamUrl)};
-
-            var response = new DownstreamResponse(new StringContent(string.Empty), HttpStatusCode.Accepted,
-                new List<KeyValuePair<string, IEnumerable<string>>>()
-                {
-                    new KeyValuePair<string, IEnumerable<string>>("Location", new List<string> {downstreamUrl})
-                });
-
-            var fAndRs = new List<HeaderFindAndReplace>
-            {
-                new HeaderFindAndReplace("Location", "{DownstreamBaseUrl}", "http://ocelot.com:123/", 0)
-            };
-
-            this.Given(x => GivenTheHttpResponse(response))
-                .And(x => GivenTheRequestIs(request))
-                .And(x => GivenTheFollowingHeaderReplacements(fAndRs))
-                .When(x => WhenICallTheReplacer())
-                .Then(x => ThenTheHeaderShouldBe("Location", "http://ocelot.com:123/test/product"))
-                .BDDfy();
-        }
-
-        [Fact]
-        public void should_replace_downstream_base_url_and_port_with_ocelot_base_url()
-        {
-            const string downstreamUrl = "http://downstream.com:123/test/product";
-
-            var request =
-                new HttpRequestMessage(HttpMethod.Get, "http://test.com") {RequestUri = new System.Uri(downstreamUrl)};
-
-            var response = new DownstreamResponse(new StringContent(string.Empty), HttpStatusCode.Accepted,
-                new List<KeyValuePair<string, IEnumerable<string>>>()
-                {
-                    new KeyValuePair<string, IEnumerable<string>>("Location", new List<string> {downstreamUrl})
-                });
-
-            var fAndRs = new List<HeaderFindAndReplace>
-            {
-                new HeaderFindAndReplace("Location", "{DownstreamBaseUrl}", "http://ocelot.com/", 0)
-            };
-
-            this.Given(x => GivenTheHttpResponse(response))
-                .And(x => GivenTheRequestIs(request))
-                .And(x => GivenTheFollowingHeaderReplacements(fAndRs))
-                .When(x => WhenICallTheReplacer())
-                .Then(x => ThenTheHeaderShouldBe("Location", "http://ocelot.com/test/product"))
-                .BDDfy();
-        }
-
-        [Fact]
-        public void should_replace_downstream_base_url_and_port_with_ocelot_base_url_and_port()
-        {
-            const string downstreamUrl = "http://downstream.com:123/test/product";
-
-            var request =
-                new HttpRequestMessage(HttpMethod.Get, "http://test.com") {RequestUri = new System.Uri(downstreamUrl)};
-
-            var response = new DownstreamResponse(new StringContent(string.Empty), HttpStatusCode.Accepted,
-                new List<KeyValuePair<string, IEnumerable<string>>>()
-                {
-                    new KeyValuePair<string, IEnumerable<string>>("Location", new List<string> {downstreamUrl})
-                });
-
-            var fAndRs = new List<HeaderFindAndReplace>
-            {
-                new HeaderFindAndReplace("Location", "{DownstreamBaseUrl}", "http://ocelot.com:321/", 0)
-            };
-
-            this.Given(x => GivenTheHttpResponse(response))
-                .And(x => GivenTheRequestIs(request))
-                .And(x => GivenTheFollowingHeaderReplacements(fAndRs))
-                .When(x => WhenICallTheReplacer())
-                .Then(x => ThenTheHeaderShouldBe("Location", "http://ocelot.com:321/test/product"))
-                .BDDfy();
-        }
-
-        private void GivenTheRequestIs(HttpRequestMessage request)
-        {
-            _request = new DownstreamRequest(request);
-        }
-
-        private void ThenTheHeadersAreNotReplaced()
-        {
-             _result.ShouldBeOfType<OkResponse>();
-            foreach (var f in _headerFindAndReplaces)
-            {
-                var values = _response.Headers.First(x => x.Key == f.Key);
-                values.Values.ToList()[f.Index].ShouldBe("test");
-            }
-        }
-
-        private void GivenTheFollowingHeaderReplacements(List<HeaderFindAndReplace> fAndRs)
-        {
-            _headerFindAndReplaces = fAndRs;
-        }
-
-        private void GivenTheHttpResponse(DownstreamResponse response)
-        {
-            _response = response;
-        }
-
-        private void WhenICallTheReplacer()
-        {
-            _result = _replacer.Replace(_response, _headerFindAndReplaces, _request);
-        }
-
-        private void ThenTheHeaderShouldBe(string key, string value)
-        {
-            var test = _response.Headers.First(x => x.Key == key);
-            test.Values.First().ShouldBe(value);
-        }
-
-        private void ThenTheHeadersAreReplaced()
-        {
-            _result.ShouldBeOfType<OkResponse>();
-            foreach (var f in _headerFindAndReplaces)
-            {
-                var values = _response.Headers.First(x => x.Key == f.Key);
-                values.Values.ToList()[f.Index].ShouldBe(f.Replace);
-            }
-        }
-    }
-}
+using Xunit;
+using Shouldly;
+using TestStack.BDDfy;
+using System.Net.Http;
+using Ocelot.Headers;
+using Ocelot.Configuration;
+using System.Collections.Generic;
+using Ocelot.Responses;
+using System.Linq;
+using System.Net;
+using Moq;
+using Ocelot.Infrastructure;
+using Ocelot.Middleware;
+using Ocelot.Infrastructure.RequestData;
+using Ocelot.Middleware.Multiplexer;
+using Ocelot.Request.Middleware;
+
+namespace Ocelot.UnitTests.Headers
+{
+    public class HttpResponseHeaderReplacerTests
+    {
+        private DownstreamResponse _response;
+        private Placeholders _placeholders;
+        private readonly HttpResponseHeaderReplacer _replacer;
+        private List<HeaderFindAndReplace> _headerFindAndReplaces;
+        private Response _result;
+        private DownstreamRequest _request;
+        private Mock<IBaseUrlFinder> _finder;
+        private Mock<IRequestScopedDataRepository> _repo;
+
+        public HttpResponseHeaderReplacerTests()
+        {
+            _repo = new Mock<IRequestScopedDataRepository>();
+            _finder = new Mock<IBaseUrlFinder>();
+            _placeholders = new Placeholders(_finder.Object, _repo.Object);
+            _replacer = new HttpResponseHeaderReplacer(_placeholders);
+        }
+
+        [Fact]
+        public void should_replace_headers()
+        {
+            var response = new DownstreamResponse(new StringContent(string.Empty), HttpStatusCode.Accepted,
+                new List<KeyValuePair<string, IEnumerable<string>>>()
+                {
+                    new KeyValuePair<string, IEnumerable<string>>("test", new List<string> {"test"})
+                }, "");
+
+            var fAndRs = new List<HeaderFindAndReplace> {new HeaderFindAndReplace("test", "test", "chiken", 0)};
+
+            this.Given(x => GivenTheHttpResponse(response))
+                .And(x => GivenTheFollowingHeaderReplacements(fAndRs))
+                .When(x => WhenICallTheReplacer())
+                .Then(x => ThenTheHeadersAreReplaced())
+                .BDDfy();
+        }
+
+        [Fact]
+        public void should_not_replace_headers()
+        {
+            var response = new DownstreamResponse(new StringContent(string.Empty), HttpStatusCode.Accepted,
+                new List<KeyValuePair<string, IEnumerable<string>>>()
+                {
+                    new KeyValuePair<string, IEnumerable<string>>("test", new List<string> {"test"})
+                }, "");
+
+            var fAndRs = new List<HeaderFindAndReplace>();
+
+            this.Given(x => GivenTheHttpResponse(response))
+                .And(x => GivenTheFollowingHeaderReplacements(fAndRs))
+                .When(x => WhenICallTheReplacer())
+                .Then(x => ThenTheHeadersAreNotReplaced())
+                .BDDfy();
+        }
+
+        [Fact]
+        public void should_replace_downstream_base_url_with_ocelot_base_url()
+        {
+            const string downstreamUrl = "http://downstream.com/";
+
+            var request =
+                new HttpRequestMessage(HttpMethod.Get, "http://test.com") {RequestUri = new System.Uri(downstreamUrl)};
+
+            var response = new DownstreamResponse(new StringContent(string.Empty), HttpStatusCode.Accepted,
+                new List<KeyValuePair<string, IEnumerable<string>>>()
+                {
+                    new KeyValuePair<string, IEnumerable<string>>("Location", new List<string> {downstreamUrl})
+                }, "");
+
+            var fAndRs = new List<HeaderFindAndReplace>
+            {
+                new HeaderFindAndReplace("Location", "{DownstreamBaseUrl}", "http://ocelot.com/", 0)
+            };
+
+            this.Given(x => GivenTheHttpResponse(response))
+                .And(x => GivenTheRequestIs(request))
+                .And(x => GivenTheFollowingHeaderReplacements(fAndRs))
+                .When(x => WhenICallTheReplacer())
+                .Then(x => ThenTheHeaderShouldBe("Location", "http://ocelot.com/"))
+                .BDDfy();
+        }
+
+        [Fact]
+        public void should_replace_downstream_base_url_with_ocelot_base_url_with_port()
+        {
+            const string downstreamUrl = "http://downstream.com/";
+
+            var request =
+                new HttpRequestMessage(HttpMethod.Get, "http://test.com") {RequestUri = new System.Uri(downstreamUrl)};
+
+            var response = new DownstreamResponse(new StringContent(string.Empty), HttpStatusCode.Accepted,
+                new List<KeyValuePair<string, IEnumerable<string>>>()
+                {
+                    new KeyValuePair<string, IEnumerable<string>>("Location", new List<string> {downstreamUrl})
+                }, "");
+
+            var fAndRs = new List<HeaderFindAndReplace>
+            {
+                new HeaderFindAndReplace("Location", "{DownstreamBaseUrl}", "http://ocelot.com:123/", 0)
+            };
+
+            this.Given(x => GivenTheHttpResponse(response))
+                .And(x => GivenTheRequestIs(request))
+                .And(x => GivenTheFollowingHeaderReplacements(fAndRs))
+                .When(x => WhenICallTheReplacer())
+                .Then(x => ThenTheHeaderShouldBe("Location", "http://ocelot.com:123/"))
+                .BDDfy();
+        }
+
+        [Fact]
+        public void should_replace_downstream_base_url_with_ocelot_base_url_and_path()
+        {
+            const string downstreamUrl = "http://downstream.com/test/product";
+
+            var request =
+                new HttpRequestMessage(HttpMethod.Get, "http://test.com") {RequestUri = new System.Uri(downstreamUrl)};
+
+            var response = new DownstreamResponse(new StringContent(string.Empty), HttpStatusCode.Accepted,
+                new List<KeyValuePair<string, IEnumerable<string>>>()
+                {
+                    new KeyValuePair<string, IEnumerable<string>>("Location", new List<string> {downstreamUrl})
+                }, "");
+
+            var fAndRs = new List<HeaderFindAndReplace>
+            {
+                new HeaderFindAndReplace("Location", "{DownstreamBaseUrl}", "http://ocelot.com/", 0)
+            };
+
+            this.Given(x => GivenTheHttpResponse(response))
+                .And(x => GivenTheRequestIs(request))
+                .And(x => GivenTheFollowingHeaderReplacements(fAndRs))
+                .When(x => WhenICallTheReplacer())
+                .Then(x => ThenTheHeaderShouldBe("Location", "http://ocelot.com/test/product"))
+                .BDDfy();
+        }
+
+        [Fact]
+        public void should_replace_downstream_base_url_with_ocelot_base_url_with_path_and_port()
+        {
+            const string downstreamUrl = "http://downstream.com/test/product";
+
+            var request =
+                new HttpRequestMessage(HttpMethod.Get, "http://test.com") {RequestUri = new System.Uri(downstreamUrl)};
+
+            var response = new DownstreamResponse(new StringContent(string.Empty), HttpStatusCode.Accepted,
+                new List<KeyValuePair<string, IEnumerable<string>>>()
+                {
+                    new KeyValuePair<string, IEnumerable<string>>("Location", new List<string> {downstreamUrl})
+                }, "");
+
+            var fAndRs = new List<HeaderFindAndReplace>
+            {
+                new HeaderFindAndReplace("Location", "{DownstreamBaseUrl}", "http://ocelot.com:123/", 0)
+            };
+
+            this.Given(x => GivenTheHttpResponse(response))
+                .And(x => GivenTheRequestIs(request))
+                .And(x => GivenTheFollowingHeaderReplacements(fAndRs))
+                .When(x => WhenICallTheReplacer())
+                .Then(x => ThenTheHeaderShouldBe("Location", "http://ocelot.com:123/test/product"))
+                .BDDfy();
+        }
+
+        [Fact]
+        public void should_replace_downstream_base_url_and_port_with_ocelot_base_url()
+        {
+            const string downstreamUrl = "http://downstream.com:123/test/product";
+
+            var request =
+                new HttpRequestMessage(HttpMethod.Get, "http://test.com") {RequestUri = new System.Uri(downstreamUrl)};
+
+            var response = new DownstreamResponse(new StringContent(string.Empty), HttpStatusCode.Accepted,
+                new List<KeyValuePair<string, IEnumerable<string>>>()
+                {
+                    new KeyValuePair<string, IEnumerable<string>>("Location", new List<string> {downstreamUrl})
+                }, "");
+
+            var fAndRs = new List<HeaderFindAndReplace>
+            {
+                new HeaderFindAndReplace("Location", "{DownstreamBaseUrl}", "http://ocelot.com/", 0)
+            };
+
+            this.Given(x => GivenTheHttpResponse(response))
+                .And(x => GivenTheRequestIs(request))
+                .And(x => GivenTheFollowingHeaderReplacements(fAndRs))
+                .When(x => WhenICallTheReplacer())
+                .Then(x => ThenTheHeaderShouldBe("Location", "http://ocelot.com/test/product"))
+                .BDDfy();
+        }
+
+        [Fact]
+        public void should_replace_downstream_base_url_and_port_with_ocelot_base_url_and_port()
+        {
+            const string downstreamUrl = "http://downstream.com:123/test/product";
+
+            var request =
+                new HttpRequestMessage(HttpMethod.Get, "http://test.com") {RequestUri = new System.Uri(downstreamUrl)};
+
+            var response = new DownstreamResponse(new StringContent(string.Empty), HttpStatusCode.Accepted,
+                new List<KeyValuePair<string, IEnumerable<string>>>()
+                {
+                    new KeyValuePair<string, IEnumerable<string>>("Location", new List<string> {downstreamUrl})
+                }, "");
+
+            var fAndRs = new List<HeaderFindAndReplace>
+            {
+                new HeaderFindAndReplace("Location", "{DownstreamBaseUrl}", "http://ocelot.com:321/", 0)
+            };
+
+            this.Given(x => GivenTheHttpResponse(response))
+                .And(x => GivenTheRequestIs(request))
+                .And(x => GivenTheFollowingHeaderReplacements(fAndRs))
+                .When(x => WhenICallTheReplacer())
+                .Then(x => ThenTheHeaderShouldBe("Location", "http://ocelot.com:321/test/product"))
+                .BDDfy();
+        }
+
+        private void GivenTheRequestIs(HttpRequestMessage request)
+        {
+            _request = new DownstreamRequest(request);
+        }
+
+        private void ThenTheHeadersAreNotReplaced()
+        {
+             _result.ShouldBeOfType<OkResponse>();
+            foreach (var f in _headerFindAndReplaces)
+            {
+                var values = _response.Headers.First(x => x.Key == f.Key);
+                values.Values.ToList()[f.Index].ShouldBe("test");
+            }
+        }
+
+        private void GivenTheFollowingHeaderReplacements(List<HeaderFindAndReplace> fAndRs)
+        {
+            _headerFindAndReplaces = fAndRs;
+        }
+
+        private void GivenTheHttpResponse(DownstreamResponse response)
+        {
+            _response = response;
+        }
+
+        private void WhenICallTheReplacer()
+        {
+            _result = _replacer.Replace(_response, _headerFindAndReplaces, _request);
+        }
+
+        private void ThenTheHeaderShouldBe(string key, string value)
+        {
+            var test = _response.Headers.First(x => x.Key == key);
+            test.Values.First().ShouldBe(value);
+        }
+
+        private void ThenTheHeadersAreReplaced()
+        {
+            _result.ShouldBeOfType<OkResponse>();
+            foreach (var f in _headerFindAndReplaces)
+            {
+                var values = _response.Headers.First(x => x.Key == f.Key);
+                values.Values.ToList()[f.Index].ShouldBe(f.Replace);
+            }
+        }
+    }
+}

test/Ocelot.UnitTests/Middleware/SimpleJsonResponseAggregatorTests.cs

@@ -49,13 +49,13 @@ namespace Ocelot.UnitTests.Middleware
 
             var billDownstreamContext = new DownstreamContext(new DefaultHttpContext())
             {
-                DownstreamResponse = new DownstreamResponse(new StringContent("Bill says hi"), HttpStatusCode.OK, new EditableList<KeyValuePair<string, IEnumerable<string>>>()),
+                DownstreamResponse = new DownstreamResponse(new StringContent("Bill says hi"), HttpStatusCode.OK, new EditableList<KeyValuePair<string, IEnumerable<string>>>(), "some reason"),
                 DownstreamReRoute = billDownstreamReRoute
             };
 
             var georgeDownstreamContext = new DownstreamContext(new DefaultHttpContext())
             {
-                DownstreamResponse = new DownstreamResponse(new StringContent("George says hi"), HttpStatusCode.OK, new List<KeyValuePair<string, IEnumerable<string>>>()),
+                DownstreamResponse = new DownstreamResponse(new StringContent("George says hi"), HttpStatusCode.OK, new List<KeyValuePair<string, IEnumerable<string>>>(), "some reason"),
                 DownstreamReRoute = georgeDownstreamReRoute
             };
 
@@ -69,6 +69,7 @@ namespace Ocelot.UnitTests.Middleware
                 .When(x => WhenIAggregate())
                 .Then(x => ThenTheContentIs(expected))
                 .And(x => ThenTheContentTypeIs("application/json"))
+                .And(x => ThenTheReasonPhraseIs("cannot return from aggregate..which reason phrase would you use?"))
                 .BDDfy();
         }
 
@@ -91,13 +92,13 @@ namespace Ocelot.UnitTests.Middleware
 
             var billDownstreamContext = new DownstreamContext(new DefaultHttpContext())
             {
-                DownstreamResponse = new DownstreamResponse(new StringContent("Bill says hi"), HttpStatusCode.OK, new List<KeyValuePair<string, IEnumerable<string>>>()),
+                DownstreamResponse = new DownstreamResponse(new StringContent("Bill says hi"), HttpStatusCode.OK, new List<KeyValuePair<string, IEnumerable<string>>>(), "some reason"),
                 DownstreamReRoute = billDownstreamReRoute
             };
 
             var georgeDownstreamContext = new DownstreamContext(new DefaultHttpContext())
             {
-                DownstreamResponse = new DownstreamResponse(new StringContent("Error"), HttpStatusCode.OK, new List<KeyValuePair<string, IEnumerable<string>>>()),
+                DownstreamResponse = new DownstreamResponse(new StringContent("Error"), HttpStatusCode.OK, new List<KeyValuePair<string, IEnumerable<string>>>(), "some reason"),
                 DownstreamReRoute = georgeDownstreamReRoute,
             };
 
@@ -116,6 +117,11 @@ namespace Ocelot.UnitTests.Middleware
                 .BDDfy();
         }
 
+        private void ThenTheReasonPhraseIs(string expected)
+        {
+            _upstreamContext.DownstreamResponse.ReasonPhrase.ShouldBe(expected);
+        }
+
         private void ThenTheErrorIsMapped()
         {
             _upstreamContext.Errors.ShouldBe(_downstreamContexts[1].Errors);

test/Ocelot.UnitTests/Middleware/UserDefinedResponseAggregatorTests.cs

@@ -43,11 +43,11 @@ namespace Ocelot.UnitTests.Middleware
             {
                 new DownstreamContext(new DefaultHttpContext())
                 {
-                    DownstreamResponse = new DownstreamResponse(new StringContent("Tom"), HttpStatusCode.OK, new List<KeyValuePair<string, IEnumerable<string>>>())
+                    DownstreamResponse = new DownstreamResponse(new StringContent("Tom"), HttpStatusCode.OK, new List<KeyValuePair<string, IEnumerable<string>>>(), "some reason")
                 },
                 new DownstreamContext(new DefaultHttpContext())
                 {
-                    DownstreamResponse = new DownstreamResponse(new StringContent("Laura"), HttpStatusCode.OK, new List<KeyValuePair<string, IEnumerable<string>>>())
+                    DownstreamResponse = new DownstreamResponse(new StringContent("Laura"), HttpStatusCode.OK, new List<KeyValuePair<string, IEnumerable<string>>>(), "some reason")
                 }
             };
 
@@ -72,11 +72,11 @@ namespace Ocelot.UnitTests.Middleware
             {
                 new DownstreamContext(new DefaultHttpContext())
                 { 
-                    DownstreamResponse = new DownstreamResponse(new StringContent("Tom"), HttpStatusCode.OK, new List<KeyValuePair<string, IEnumerable<string>>>())
+                    DownstreamResponse = new DownstreamResponse(new StringContent("Tom"), HttpStatusCode.OK, new List<KeyValuePair<string, IEnumerable<string>>>(), "some reason")
                 },
                 new DownstreamContext(new DefaultHttpContext())
                 {
-                    DownstreamResponse = new DownstreamResponse(new StringContent("Laura"), HttpStatusCode.OK, new List<KeyValuePair<string, IEnumerable<string>>>())
+                    DownstreamResponse = new DownstreamResponse(new StringContent("Laura"), HttpStatusCode.OK, new List<KeyValuePair<string, IEnumerable<string>>>(), "some reason")
                 }
             };
 
@@ -146,7 +146,7 @@ namespace Ocelot.UnitTests.Middleware
                 var laura = await responses[1].Content.ReadAsStringAsync();
                 var content = $"{tom}, {laura}";
                 var headers = responses.SelectMany(x => x.Headers).ToList();
-                return new DownstreamResponse(new StringContent(content), HttpStatusCode.OK, headers);
+                return new DownstreamResponse(new StringContent(content), HttpStatusCode.OK, headers, "some reason");
             }
         }
     }

test/Ocelot.UnitTests/Responder/HttpContextResponderTests.cs

@@ -3,6 +3,7 @@ using System.Linq;
 using System.Net;
 using System.Net.Http;
 using Microsoft.AspNetCore.Http;
+using Microsoft.AspNetCore.Http.Features;
 using Ocelot.Headers;
 using Ocelot.Middleware;
 using Ocelot.Middleware.Multiplexer;
@@ -31,7 +32,7 @@ namespace Ocelot.UnitTests.Responder
                 new List<KeyValuePair<string, IEnumerable<string>>>
                 {
                     new KeyValuePair<string, IEnumerable<string>>("Transfer-Encoding", new List<string> {"woop"})
-                });
+                }, "some reason");
 
             _responder.SetResponseOnHttpContext(httpContext, response).GetAwaiter().GetResult();
             var header = httpContext.Response.Headers["Transfer-Encoding"];
@@ -43,7 +44,7 @@ namespace Ocelot.UnitTests.Responder
         {
             var httpContext = new DefaultHttpContext();
             var response = new DownstreamResponse(new StringContent("test"), HttpStatusCode.OK,
-                new List<KeyValuePair<string, IEnumerable<string>>>());
+                new List<KeyValuePair<string, IEnumerable<string>>>(), "some reason");
 
             _responder.SetResponseOnHttpContext(httpContext, response).GetAwaiter().GetResult();
             var header = httpContext.Response.Headers["Content-Length"];
@@ -58,13 +59,28 @@ namespace Ocelot.UnitTests.Responder
                 new List<KeyValuePair<string, IEnumerable<string>>>
                 {
                     new KeyValuePair<string, IEnumerable<string>>("test", new List<string> {"test"})
-                });
+                }, "some reason");
 
             _responder.SetResponseOnHttpContext(httpContext, response).GetAwaiter().GetResult();
             var header = httpContext.Response.Headers["test"];
             header.First().ShouldBe("test");
         }
 
+
+        [Fact]
+        public void should_add_reason_phrase()
+        {
+            var httpContext = new DefaultHttpContext();
+            var response = new DownstreamResponse(new StringContent(""), HttpStatusCode.OK,
+                new List<KeyValuePair<string, IEnumerable<string>>>
+                {
+                    new KeyValuePair<string, IEnumerable<string>>("test", new List<string> {"test"})
+                }, "some reason");
+
+            _responder.SetResponseOnHttpContext(httpContext, response).GetAwaiter().GetResult();
+            httpContext.Response.HttpContext.Features.Get<IHttpResponseFeature>().ReasonPhrase.ShouldBe(response.ReasonPhrase);
+        }
+
         [Fact]
         public void should_call_without_exception()
         {