Merge branch 'pitming-feature/MethodTransformer'

docs/features/configuration.rst

@@ -24,6 +24,7 @@ Here is an example ReRoute configuration, You don't need to set all of these thi
             "UpstreamHttpMethod": [
                 "Get"
             ],
+            "DownstreamHttpMethod": "",
             "AddHeadersToRequest": {},
             "AddClaimsToRequest": {},
             "RouteClaimsRequirement": {},

docs/features/methodtransformation.rst

@@ -0,0 +1,28 @@
+HTTP Method Transformation
+==========================
+
+Ocelot allows the user to change the HTTP request method that will be used when making a request to a downstream service.
+
+This achieved by setting the following ReRoute configuration:
+
+.. code-block:: json
+
+{
+    "DownstreamPathTemplate": "/{url}",
+    "UpstreamPathTemplate": "/{url}",
+    "UpstreamHttpMethod": [
+        "Get"
+    ],
+    "DownstreamHttpMethod": "POST",
+    "DownstreamScheme": "http",
+    "DownstreamHostAndPorts": [
+        {
+            "Host": "localhost",
+            "Port": 53271
+        }
+    ],
+}
+
+The key property here is DownstreamHttpMethod which is set as POST and the ReRoute will only match on GET as set by UpstreamHttpMethod.
+
+This feature can be useful when interacting with downstream apis that only support POST and you want to present some kind of RESTful interface.

samples/OcelotKube/ApiGateway/Startup.cs

@@ -1,6 +1,7 @@
 using Microsoft.AspNetCore.Builder;
 using Microsoft.AspNetCore.Hosting;
 using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.Hosting;
 using Ocelot.DependencyInjection;
 using Ocelot.Middleware;
 using Ocelot.Provider.Kubernetes;
@@ -18,7 +19,7 @@ namespace ApiGateway
         }
 
         // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
-        public void Configure(IApplicationBuilder app, IHostingEnvironment env)
+        public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
         {
             if (env.IsDevelopment())
             {

samples/OcelotKube/DownstreamService/Startup.cs

@@ -7,6 +7,7 @@ using Microsoft.AspNetCore.Hosting;
 using Microsoft.AspNetCore.Mvc;
 using Microsoft.Extensions.Configuration;
 using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.Hosting;
 using Microsoft.Extensions.Logging;
 using Microsoft.Extensions.Options;
 
@@ -28,7 +29,7 @@ namespace DownstreamService
         }
 
         // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
-        public void Configure(IApplicationBuilder app, IHostingEnvironment env)
+        public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
         {
             if (env.IsDevelopment())
             {

src/Ocelot/Configuration/Builder/DownstreamReRouteBuilder.cs

@@ -41,6 +41,7 @@ namespace Ocelot.Configuration.Builder
         private List<AddHeader> _addHeadersToUpstream;
         private bool _dangerousAcceptAnyServerCertificateValidator;
         private SecurityOptions _securityOptions;
+        private string _downstreamHttpMethod;
 
         public DownstreamReRouteBuilder()
         {
@@ -56,6 +57,12 @@ namespace Ocelot.Configuration.Builder
             return this;
         }
 
+        public DownstreamReRouteBuilder WithDownStreamHttpMethod(string method)
+        {
+            _downstreamHttpMethod = method;
+            return this;
+        }
+
         public DownstreamReRouteBuilder WithLoadBalancerOptions(LoadBalancerOptions loadBalancerOptions)
         {
             _loadBalancerOptions = loadBalancerOptions;
@@ -282,7 +289,8 @@ namespace Ocelot.Configuration.Builder
                 _addHeadersToDownstream,
                 _addHeadersToUpstream,
                 _dangerousAcceptAnyServerCertificateValidator,
-                _securityOptions);
+                _securityOptions,
+                _downstreamHttpMethod);
         }
     }
 }

src/Ocelot/Configuration/Creator/ReRoutesCreator.cs

@@ -138,6 +138,7 @@ namespace Ocelot.Configuration.Creator
                 .WithAddHeadersToUpstream(hAndRs.AddHeadersToUpstream)
                 .WithDangerousAcceptAnyServerCertificateValidator(fileReRoute.DangerousAcceptAnyServerCertificateValidator)
                 .WithSecurityOptions(securityOptions)
+                .WithDownStreamHttpMethod(fileReRoute.DownstreamHttpMethod)
                 .Build();
 
             return reRoute;

src/Ocelot/Configuration/DownstreamReRoute.cs

@@ -38,7 +38,8 @@ namespace Ocelot.Configuration
             List<AddHeader> addHeadersToDownstream,
             List<AddHeader> addHeadersToUpstream,
             bool dangerousAcceptAnyServerCertificateValidator,
-            SecurityOptions securityOptions)
+            SecurityOptions securityOptions,
+            string downstreamHttpMethod)
         {
             DangerousAcceptAnyServerCertificateValidator = dangerousAcceptAnyServerCertificateValidator;
             AddHeadersToDownstream = addHeadersToDownstream;
@@ -72,6 +73,7 @@ namespace Ocelot.Configuration
             LoadBalancerKey = loadBalancerKey;
             AddHeadersToUpstream = addHeadersToUpstream;
             SecurityOptions = securityOptions;
+            DownstreamHttpMethod = downstreamHttpMethod;
         }
 
         public string Key { get; }
@@ -106,5 +108,6 @@ namespace Ocelot.Configuration
         public List<AddHeader> AddHeadersToUpstream { get; }
         public bool DangerousAcceptAnyServerCertificateValidator { get; }
         public SecurityOptions SecurityOptions { get; }
+        public string DownstreamHttpMethod { get; }
     }
 }

src/Ocelot/Configuration/File/FileReRoute.cs

@@ -29,6 +29,7 @@ namespace Ocelot.Configuration.File
         public string DownstreamPathTemplate { get; set; }
         public string UpstreamPathTemplate { get; set; }
         public List<string> UpstreamHttpMethod { get; set; }
+        public string DownstreamHttpMethod { get; set; }
         public Dictionary<string, string> AddHeadersToRequest { get; set; }
         public Dictionary<string, string> UpstreamHeaderTransform { get; set; }
         public Dictionary<string, string> DownstreamHeaderTransform { get; set; }

src/Ocelot/Request/Mapper/IRequestMapper.cs

@@ -1,12 +1,13 @@
 namespace Ocelot.Request.Mapper
 {
     using Microsoft.AspNetCore.Http;
+    using Ocelot.Configuration;
     using Ocelot.Responses;
     using System.Net.Http;
     using System.Threading.Tasks;
 
     public interface IRequestMapper
     {
-        Task<Response<HttpRequestMessage>> Map(HttpRequest request);
+        Task<Response<HttpRequestMessage>> Map(HttpRequest request, DownstreamReRoute downstreamReRoute);
     }
 }

src/Ocelot/Request/Mapper/RequestMapper.cs

@@ -3,6 +3,7 @@
     using Microsoft.AspNetCore.Http;
     using Microsoft.AspNetCore.Http.Extensions;
     using Microsoft.Extensions.Primitives;
+    using Ocelot.Configuration;
     using Ocelot.Responses;
     using System;
     using System.Collections.Generic;
@@ -15,14 +16,14 @@
     {
         private readonly string[] _unsupportedHeaders = { "host" };
 
-        public async Task<Response<HttpRequestMessage>> Map(HttpRequest request)
+        public async Task<Response<HttpRequestMessage>> Map(HttpRequest request, DownstreamReRoute downstreamReRoute)
         {
             try
             {
                 var requestMessage = new HttpRequestMessage()
                 {
                     Content = await MapContent(request),
-                    Method = MapMethod(request),
+                    Method = MapMethod(request, downstreamReRoute),
                     RequestUri = MapUri(request)
                 };
 
@@ -71,8 +72,13 @@
             }
         }
 
-        private HttpMethod MapMethod(HttpRequest request)
+        private HttpMethod MapMethod(HttpRequest request, DownstreamReRoute downstreamReRoute)
         {
+            if (!string.IsNullOrEmpty(downstreamReRoute?.DownstreamHttpMethod))
+            {
+                return new HttpMethod(downstreamReRoute.DownstreamHttpMethod);
+            }
+
             return new HttpMethod(request.Method);
         }
 

src/Ocelot/Request/Middleware/DownstreamRequest.cs

@@ -52,6 +52,7 @@ namespace Ocelot.Request.Middleware
             };
 
             _request.RequestUri = uriBuilder.Uri;
+            _request.Method = new HttpMethod(Method);
             return _request;
         }
 

src/Ocelot/Request/Middleware/DownstreamRequestInitialiserMiddleware.cs

@@ -24,7 +24,7 @@ namespace Ocelot.Request.Middleware
 
         public async Task Invoke(DownstreamContext context)
         {
-            var downstreamRequest = await _requestMapper.Map(context.HttpContext.Request);
+            var downstreamRequest = await _requestMapper.Map(context.HttpContext.Request, context.DownstreamReRoute);
 
             if (downstreamRequest.IsError)
             {

src/Ocelot/Request/Middleware/HttpRequestBuilderMiddlewareExtensions.cs

@@ -1,4 +1,3 @@
-using Microsoft.AspNetCore.Builder;
 using Ocelot.Middleware.Pipeline;
 
 namespace Ocelot.Request.Middleware

test/Ocelot.AcceptanceTests/MethodTests.cs

@@ -0,0 +1,158 @@
+namespace Ocelot.AcceptanceTests
+{
+    using Microsoft.AspNetCore.Http;
+    using Ocelot.Configuration.File;
+    using System;
+    using System.Collections.Generic;
+    using System.IO;
+    using System.Net;
+    using System.Net.Http;
+    using TestStack.BDDfy;
+    using Xunit;
+
+    public class MethodTests : IDisposable
+    {
+        private readonly Steps _steps;
+        private readonly ServiceHandler _serviceHandler;
+
+        public MethodTests()
+        {
+            _serviceHandler = new ServiceHandler();
+            _steps = new Steps();
+        }
+
+        [Fact]
+        public void should_return_response_200_when_get_converted_to_post()
+        {
+            var configuration = new FileConfiguration
+            {
+                ReRoutes = new List<FileReRoute>
+                    {
+                        new FileReRoute
+                        {
+                            DownstreamPathTemplate = "/{url}",
+                            DownstreamScheme = "http",
+                            UpstreamPathTemplate = "/{url}",
+                            UpstreamHttpMethod = new List<string> { "Get" },
+                            DownstreamHostAndPorts = new List<FileHostAndPort>
+                            {
+                                new FileHostAndPort
+                                {
+                                    Host = "localhost",
+                                    Port = 53171,
+                                },
+                            },
+                            DownstreamHttpMethod = "POST",
+                        },
+                    },
+            };
+
+            this.Given(x => x.GivenThereIsAServiceRunningOn("http://localhost:53171/", "/", "POST"))
+                .And(x => _steps.GivenThereIsAConfiguration(configuration))
+                .And(x => _steps.GivenOcelotIsRunning())
+                .When(x => _steps.WhenIGetUrlOnTheApiGateway("/"))
+                .Then(x => _steps.ThenTheStatusCodeShouldBe(HttpStatusCode.OK))
+                .BDDfy();
+        }
+
+        [Fact]
+        public void should_return_response_200_when_get_converted_to_post_with_content()
+        {
+            var configuration = new FileConfiguration
+            {
+                ReRoutes = new List<FileReRoute>
+                {
+                    new FileReRoute
+                    {
+                        DownstreamPathTemplate = "/{url}",
+                        DownstreamScheme = "http",
+                        UpstreamPathTemplate = "/{url}",
+                        UpstreamHttpMethod = new List<string> { "Get" },
+                        DownstreamHostAndPorts = new List<FileHostAndPort>
+                        {
+                            new FileHostAndPort
+                            {
+                                Host = "localhost",
+                                Port = 53271,
+                            },
+                        },
+                        DownstreamHttpMethod = "POST",
+                    },
+                },
+            };
+
+            const string expected = "here is some content";
+            var httpContent = new StringContent(expected);
+
+            this.Given(x => x.GivenThereIsAServiceRunningOn("http://localhost:53271/", "/", "POST"))
+                .And(x => _steps.GivenThereIsAConfiguration(configuration))
+                .And(x => _steps.GivenOcelotIsRunning())
+                .When(x => _steps.WhenIGetUrlOnTheApiGateway("/", httpContent))
+                .Then(x => _steps.ThenTheStatusCodeShouldBe(HttpStatusCode.OK))
+                .And(_ => _steps.ThenTheResponseBodyShouldBe(expected))
+                .BDDfy();
+        }
+
+        [Fact]
+        public void should_return_response_200_when_get_converted_to_get_with_content()
+        {
+            var configuration = new FileConfiguration
+            {
+                ReRoutes = new List<FileReRoute>
+                {
+                    new FileReRoute
+                    {
+                        DownstreamPathTemplate = "/{url}",
+                        DownstreamScheme = "http",
+                        UpstreamPathTemplate = "/{url}",
+                        UpstreamHttpMethod = new List<string> { "Post" },
+                        DownstreamHostAndPorts = new List<FileHostAndPort>
+                        {
+                            new FileHostAndPort
+                            {
+                                Host = "localhost",
+                                Port = 53272,
+                            },
+                        },
+                        DownstreamHttpMethod = "GET",
+                    },
+                },
+            };
+
+            const string expected = "here is some content";
+            var httpContent = new StringContent(expected);
+
+            this.Given(x => x.GivenThereIsAServiceRunningOn("http://localhost:53272/", "/", "GET"))
+                .And(x => _steps.GivenThereIsAConfiguration(configuration))
+                .And(x => _steps.GivenOcelotIsRunning())
+                .When(x => _steps.WhenIPostUrlOnTheApiGateway("/", httpContent))
+                .Then(x => _steps.ThenTheStatusCodeShouldBe(HttpStatusCode.OK))
+                .And(_ => _steps.ThenTheResponseBodyShouldBe(expected))
+                .BDDfy();
+        }
+
+        private void GivenThereIsAServiceRunningOn(string baseUrl, string basePath, string expected)
+        {
+            _serviceHandler.GivenThereIsAServiceRunningOn(baseUrl, basePath, async context =>
+            {
+                if (context.Request.Method == expected)
+                {
+                    context.Response.StatusCode = 200;
+                    var reader = new StreamReader(context.Request.Body);
+                    var body = await reader.ReadToEndAsync();
+                    await context.Response.WriteAsync(body);
+                }
+                else
+                {
+                    context.Response.StatusCode = 500;
+                }
+            });
+        }
+
+        public void Dispose()
+        {
+            _serviceHandler.Dispose();
+            _steps.Dispose();
+        }
+    }
+}

test/Ocelot.AcceptanceTests/Steps.cs

@@ -909,6 +909,18 @@ namespace Ocelot.AcceptanceTests
             _response = _ocelotClient.GetAsync(url).Result;
         }
 
+        public void WhenIGetUrlOnTheApiGateway(string url, HttpContent content)
+        {
+            var httpRequestMessage = new HttpRequestMessage(HttpMethod.Get, url) {Content = content};
+            _response = _ocelotClient.SendAsync(httpRequestMessage).Result;
+        }
+
+        public void WhenIPostUrlOnTheApiGateway(string url, HttpContent content)
+        {
+            var httpRequestMessage = new HttpRequestMessage(HttpMethod.Post, url) { Content = content };
+            _response = _ocelotClient.SendAsync(httpRequestMessage).Result;
+        }
+
         public void WhenIGetUrlOnTheApiGateway(string url, string cookie, string value)
         {
             var request = _ocelotServer.CreateRequest(url);

test/Ocelot.UnitTests/Request/DownstreamRequestInitialiserMiddlewareTests.cs

@@ -1,6 +1,4 @@
-using Ocelot.Middleware;
-
-namespace Ocelot.UnitTests.Request
+namespace Ocelot.UnitTests.Request
 {
     using Microsoft.AspNetCore.Http;
     using Moq;
@@ -9,9 +7,12 @@ namespace Ocelot.UnitTests.Request
     using Ocelot.Request.Creator;
     using Ocelot.Request.Mapper;
     using Ocelot.Request.Middleware;
+    using Ocelot.Configuration.Builder;
+    using Ocelot.Middleware;
     using Ocelot.Responses;
     using Shouldly;
     using System.Net.Http;
+    using Ocelot.Configuration;
     using TestStack.BDDfy;
     using Xunit;
 
@@ -65,6 +66,20 @@ namespace Ocelot.UnitTests.Request
                 .Then(_ => ThenTheContexRequestIsMappedToADownstreamRequest())
                 .And(_ => ThenTheDownstreamRequestIsStored())
                 .And(_ => ThenTheNextMiddlewareIsInvoked())
+                .And(_ => ThenTheDownstreamRequestMethodIs("GET"))
+                .BDDfy();
+        }
+
+        [Fact]
+        public void Should_map_downstream_reroute_method_to_downstream_request()
+        {
+            this.Given(_ => GivenTheHttpContextContainsARequest())
+                .And(_ => GivenTheMapperWillReturnAMappedRequest())
+                .When(_ => WhenTheMiddlewareIsInvoked())
+                .Then(_ => ThenTheContexRequestIsMappedToADownstreamRequest())
+                .And(_ => ThenTheDownstreamRequestIsStored())
+                .And(_ => ThenTheNextMiddlewareIsInvoked())
+                .And(_ => ThenTheDownstreamRequestMethodIs("GET"))
                 .BDDfy();
         }
 
@@ -80,6 +95,11 @@ namespace Ocelot.UnitTests.Request
                 .BDDfy();
         }
 
+        private void ThenTheDownstreamRequestMethodIs(string expected)
+        {
+            _downstreamContext.DownstreamRequest.Method.ShouldBe(expected);
+        }
+
         private void GivenTheHttpContextContainsARequest()
         {
             _httpContext
@@ -92,7 +112,7 @@ namespace Ocelot.UnitTests.Request
             _mappedRequest = new OkResponse<HttpRequestMessage>(new HttpRequestMessage(HttpMethod.Get, "http://www.bbc.co.uk"));
 
             _requestMapper
-                .Setup(rm => rm.Map(It.IsAny<HttpRequest>()))
+                .Setup(rm => rm.Map(It.IsAny<HttpRequest>(), It.IsAny<DownstreamReRoute>()))
                 .ReturnsAsync(_mappedRequest);
         }
 
@@ -101,7 +121,7 @@ namespace Ocelot.UnitTests.Request
             _mappedRequest = new ErrorResponse<HttpRequestMessage>(new UnmappableRequestError(new System.Exception("boooom!")));
 
             _requestMapper
-                .Setup(rm => rm.Map(It.IsAny<HttpRequest>()))
+                .Setup(rm => rm.Map(It.IsAny<HttpRequest>(), It.IsAny<DownstreamReRoute>()))
                 .ReturnsAsync(_mappedRequest);
         }
 
@@ -112,7 +132,7 @@ namespace Ocelot.UnitTests.Request
 
         private void ThenTheContexRequestIsMappedToADownstreamRequest()
         {
-            _requestMapper.Verify(rm => rm.Map(_httpRequest.Object), Times.Once);
+            _requestMapper.Verify(rm => rm.Map(_httpRequest.Object, _downstreamContext.DownstreamReRoute), Times.Once);
         }
 
         private void ThenTheDownstreamRequestIsStored()

test/Ocelot.UnitTests/Request/Mapper/RequestMapperTests.cs

@@ -13,6 +13,8 @@
     using System.Security.Cryptography;
     using System.Text;
     using System.Threading.Tasks;
+    using Ocelot.Configuration;
+    using Ocelot.Configuration.Builder;
     using TestStack.BDDfy;
     using Xunit;
 
@@ -27,6 +29,8 @@
 
         private List<KeyValuePair<string, StringValues>> _inputHeaders = null;
 
+        private DownstreamReRoute _downstreamReRoute;
+
         public RequestMapperTests()
         {
             _httpContext = new DefaultHttpContext();
@@ -82,6 +86,21 @@
                 .BDDfy();
         }
 
+        [Theory]
+        [InlineData("", "GET")]
+        [InlineData(null, "GET")]
+        [InlineData("POST", "POST")]
+        public void Should_use_downstream_reroute_method_if_set(string input, string expected)
+        {
+            this.Given(_ => GivenTheInputRequestHasMethod("GET"))
+                .And(_ => GivenTheDownstreamReRouteMethodIs(input))
+                .And(_ => GivenTheInputRequestHasAValidUri())
+                .When(_ => WhenMapped())
+                .Then(_ => ThenNoErrorIsReturned())
+                .And(_ => ThenTheMappedRequestHasMethod(expected))
+                .BDDfy();
+        }
+
         [Fact]
         public void Should_map_all_headers()
         {
@@ -154,16 +173,6 @@
                 .BDDfy();
         }
 
-        private void GivenTheInputRequestHasNoContentLength()
-        {
-            _inputRequest.ContentLength = null;
-        }
-
-        private void GivenTheInputRequestHasNoContentType()
-        {
-            _inputRequest.ContentType = null;
-        }
-
         [Fact]
         public void Should_map_content_headers()
         {
@@ -212,6 +221,22 @@
                 .BDDfy();
         }
 
+        private void GivenTheDownstreamReRouteMethodIs(string input)
+        {
+            _downstreamReRoute = new DownstreamReRouteBuilder().WithDownStreamHttpMethod(input).Build();
+        }
+
+        private void GivenTheInputRequestHasNoContentLength()
+        {
+            _inputRequest.ContentLength = null;
+        }
+
+        private void GivenTheInputRequestHasNoContentType()
+        {
+            _inputRequest.ContentType = null;
+        }
+
+
         private void ThenTheContentHeadersAreNotAddedToNonContentHeaders()
         {
             _mappedRequest.Data.Headers.ShouldNotContain(x => x.Key == "Content-Disposition");
@@ -380,7 +405,7 @@
 
         private async Task WhenMapped()
         {
-            _mappedRequest = await _requestMapper.Map(_inputRequest);
+            _mappedRequest = await _requestMapper.Map(_inputRequest, _downstreamReRoute);
         }
 
         private void ThenNoErrorIsReturned()