allowing people to inject functions as custom middleware

src/Ocelot/Configuration/Provider/OcelotConfigurationProvider.cs

@@ -7,12 +7,12 @@ namespace Ocelot.Configuration.Provider
     /// <summary>
     /// Register as singleton
     /// </summary>
-    public class YamlOcelotConfigurationProvider : IOcelotConfigurationProvider
+    public class OcelotConfigurationProvider : IOcelotConfigurationProvider
     {
         private readonly IOcelotConfigurationRepository _repo;
         private readonly IOcelotConfigurationCreator _creator;
 
-        public YamlOcelotConfigurationProvider(IOcelotConfigurationRepository repo, 
+        public OcelotConfigurationProvider(IOcelotConfigurationRepository repo, 
             IOcelotConfigurationCreator creator)
         {
             _repo = repo;
@@ -21,28 +21,28 @@ namespace Ocelot.Configuration.Provider
 
         public Response<IOcelotConfiguration> Get()
         {
-            var config = _repo.Get();
+            var repoConfig = _repo.Get();
 
-            if (config.IsError)
+            if (repoConfig.IsError)
             {
-                return new ErrorResponse<IOcelotConfiguration>(config.Errors);
+                return new ErrorResponse<IOcelotConfiguration>(repoConfig.Errors);
             }
 
-            if (config.Data == null)
+            if (repoConfig.Data == null)
             {
-                var configuration = _creator.Create();
+                var creatorConfig = _creator.Create();
 
-                if (configuration.IsError)
+                if (creatorConfig.IsError)
                 {
-                    return new ErrorResponse<IOcelotConfiguration>(configuration.Errors);
+                    return new ErrorResponse<IOcelotConfiguration>(creatorConfig.Errors);
                 }
 
-                _repo.AddOrReplace(configuration.Data);
+                _repo.AddOrReplace(creatorConfig.Data);
 
-                return new OkResponse<IOcelotConfiguration>(configuration.Data);
+                return new OkResponse<IOcelotConfiguration>(creatorConfig.Data);
             }
 
-            return new OkResponse<IOcelotConfiguration>(config.Data);
+            return new OkResponse<IOcelotConfiguration>(repoConfig.Data);
         }
     }
 }

src/Ocelot/DependencyInjection/ServiceCollectionExtensions.cs

@@ -34,7 +34,7 @@ namespace Ocelot.DependencyInjection
 
             // ocelot services.
             services.AddSingleton<IOcelotConfigurationCreator, YamlOcelotConfigurationCreator>();
-            services.AddSingleton<IOcelotConfigurationProvider, YamlOcelotConfigurationProvider>();
+            services.AddSingleton<IOcelotConfigurationProvider, OcelotConfigurationProvider>();
             services.AddSingleton<IOcelotConfigurationRepository, InMemoryOcelotConfigurationRepository>();
             services.AddSingleton<IClaimToThingConfigurationParser, ClaimToThingConfigurationParser>();
             services.AddSingleton<IConfigurationValidator, ConfigurationValidator>();

src/Ocelot/Middleware/OcelotMiddlewareConfiguration.cs

@@ -0,0 +1,27 @@
+namespace Ocelot.Middleware
+{
+    using System;
+    using System.Threading.Tasks;
+    using Microsoft.AspNetCore.Http;
+
+    public class OcelotMiddlewareConfiguration
+    {
+        public Func<HttpContext, Func<Task>, Task> PreHttpResponderMiddleware { get; set; }
+        public Func<HttpContext, Func<Task>, Task> PostHttpResponderMiddleware { get; set; }
+        public Func<HttpContext, Func<Task>, Task> PreDownstreamRouteFinderMiddleware { get; set; }
+        public Func<HttpContext, Func<Task>, Task> PostDownstreamRouteFinderMiddleware { get; set; }
+        public Func<HttpContext, Func<Task>, Task> PreAuthenticationMiddleware { get; set; }
+        public Func<HttpContext, Func<Task>, Task> PostAuthenticationMiddleware { get; set; }
+        public Func<HttpContext, Func<Task>, Task> PreClaimsBuilderMiddleware { get; set; }
+        public Func<HttpContext, Func<Task>, Task> PostClaimsBuilderMiddleware { get; set; }
+        public Func<HttpContext, Func<Task>, Task> PreAuthorisationMiddleware { get; set; }
+        public Func<HttpContext, Func<Task>, Task> PostAuthorisationMiddleware { get; set; }
+        public Func<HttpContext, Func<Task>, Task> PreHttpRequestHeadersBuilderMiddleware { get; set; }
+        public Func<HttpContext, Func<Task>, Task> PostHttpRequestHeadersBuilderMiddleware { get; set; }
+        public Func<HttpContext, Func<Task>, Task> PreDownstreamUrlCreatorMiddleware { get; set; }
+        public Func<HttpContext, Func<Task>, Task> PostDownstreamUrlCreatorMiddleware { get; set; }
+        public Func<HttpContext, Func<Task>, Task> PreHttpRequestBuilderMiddleware { get; set; }
+        public Func<HttpContext, Func<Task>, Task> PostHttpRequestBuilderMiddleware { get; set; }
+        public Func<HttpContext, Func<Task>, Task> PreHttpRequesterMiddleware { get; set; }
+    }
+}

src/Ocelot/Middleware/OcelotMiddlewareExtensions.cs

@@ -9,8 +9,11 @@ using Ocelot.Responder.Middleware;
 
 namespace Ocelot.Middleware
 {
+    using System;
+    using System.Threading.Tasks;
     using Authorisation.Middleware;
     using ClaimsBuilder.Middleware;
+    using Microsoft.AspNetCore.Http;
 
     public static class OcelotMiddlewareExtensions
     {
@@ -36,5 +39,70 @@ namespace Ocelot.Middleware
 
             return builder;
         }
+
+        public static IApplicationBuilder UseOcelot(this IApplicationBuilder builder, OcelotMiddlewareConfiguration middlewareConfiguration)
+        {
+            builder.UseIfNotNull(middlewareConfiguration.PreHttpResponderMiddleware);
+
+            builder.UseHttpResponderMiddleware();
+
+            builder.UseIfNotNull(middlewareConfiguration.PostHttpResponderMiddleware);
+
+            builder.UseIfNotNull(middlewareConfiguration.PreDownstreamRouteFinderMiddleware);
+
+            builder.UseDownstreamRouteFinderMiddleware();
+
+            builder.UseIfNotNull(middlewareConfiguration.PostDownstreamRouteFinderMiddleware);
+
+            builder.UseIfNotNull(middlewareConfiguration.PreAuthenticationMiddleware);
+
+            builder.UseAuthenticationMiddleware();
+
+            builder.UseIfNotNull(middlewareConfiguration.PostAuthenticationMiddleware);
+
+            builder.UseIfNotNull(middlewareConfiguration.PreClaimsBuilderMiddleware);
+
+            builder.UseClaimsBuilderMiddleware();
+
+            builder.UseIfNotNull(middlewareConfiguration.PostClaimsBuilderMiddleware);
+
+            builder.UseIfNotNull(middlewareConfiguration.PreAuthorisationMiddleware);
+
+            builder.UseAuthorisationMiddleware();
+
+            builder.UseIfNotNull(middlewareConfiguration.PostAuthorisationMiddleware);
+
+            builder.UseIfNotNull(middlewareConfiguration.PreHttpRequestHeadersBuilderMiddleware);
+
+            builder.UseHttpRequestHeadersBuilderMiddleware();
+
+            builder.UseIfNotNull(middlewareConfiguration.PostHttpRequestHeadersBuilderMiddleware);
+
+            builder.UseIfNotNull(middlewareConfiguration.PreDownstreamUrlCreatorMiddleware);
+
+            builder.UseDownstreamUrlCreatorMiddleware();
+
+            builder.UseIfNotNull(middlewareConfiguration.PostDownstreamUrlCreatorMiddleware);
+
+            builder.UseIfNotNull(middlewareConfiguration.PreHttpRequestBuilderMiddleware);
+
+            builder.UseHttpRequestBuilderMiddleware();
+
+            builder.UseIfNotNull(middlewareConfiguration.PostHttpRequestBuilderMiddleware);
+
+            builder.UseIfNotNull(middlewareConfiguration.PreHttpRequesterMiddleware);
+
+            builder.UseHttpRequesterMiddleware();
+
+            return builder;
+        }
+
+        private static void UseIfNotNull(this IApplicationBuilder builder, Func<HttpContext, Func<Task>, Task> middleware)
+        {
+            if (middleware != null)
+            {
+                builder.Use(middleware);
+            }
+        }
     }
 }

test/Ocelot.AcceptanceTests/CustomMiddlewareTests.cs

@@ -0,0 +1,201 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Net;
+using System.Net.Http;
+using Microsoft.AspNetCore.Builder;
+using Microsoft.AspNetCore.Hosting;
+using Microsoft.AspNetCore.Http;
+using Microsoft.AspNetCore.TestHost;
+using Ocelot.Configuration.Yaml;
+using Shouldly;
+using TestStack.BDDfy;
+using Xunit;
+using YamlDotNet.Serialization;
+
+namespace Ocelot.AcceptanceTests
+{
+    using System.Linq;
+    using System.Threading.Tasks;
+    using DependencyInjection;
+    using Microsoft.Extensions.Configuration;
+    using Microsoft.Extensions.DependencyInjection;
+    using Microsoft.Extensions.Logging;
+    using Microsoft.Extensions.Primitives;
+    using Middleware;
+    using ScopedData;
+
+    public class CustomMiddlewareTests : IDisposable
+    {
+        private TestServer _server;
+        private HttpClient _client;
+        private HttpResponseMessage _response;
+        private readonly string _configurationPath;
+        private StringContent _postContent;
+        private IWebHost _builder;
+
+        // Sadly we need to change this when we update the netcoreapp version to make the test update the config correctly
+        private double _netCoreAppVersion = 1.4;
+
+        public CustomMiddlewareTests()
+        {
+            _configurationPath = $"configuration.yaml";
+        }
+
+        [Fact]
+        public void response_should_come_from_pre_http_responder_middleware()
+        {
+            var configuration = new OcelotMiddlewareConfiguration
+            {
+                PreHttpResponderMiddleware = async (ctx, next) =>
+                {
+                    await ctx.Response.WriteAsync("PreHttpResponderMiddleware");
+                }
+            };
+
+            this.Given(x => x.GivenThereIsAServiceRunningOn("http://localhost:41879", 200))
+                .And(x => x.GivenThereIsAConfiguration(new YamlConfiguration
+                {
+                    ReRoutes = new List<YamlReRoute>
+                    {
+                        new YamlReRoute
+                        {
+                            DownstreamTemplate = "http://localhost:41879/",
+                            UpstreamTemplate = "/",
+                            UpstreamHttpMethod = "Get",
+                        }
+                    }
+                }))
+                .And(x => x.GivenTheApiGatewayIsRunning(configuration))
+                .When(x => x.WhenIGetUrlOnTheApiGateway("/"))
+                .Then(x => x.ThenTheStatusCodeShouldBe(HttpStatusCode.OK))
+                .And(x => x.ThenTheResponseBodyShouldBe("PreHttpResponderMiddleware"))
+                .BDDfy();
+        }
+
+        [Fact]
+        public void response_should_come_from_pre_http_requester_middleware()
+        {
+            var configuration = new OcelotMiddlewareConfiguration
+            {
+                PreHttpRequesterMiddleware = async (ctx, next) =>
+                {
+                    var service = ctx.RequestServices.GetService<IScopedRequestDataRepository>();
+                    service.Add("Response",
+                        new HttpResponseMessage {Content = new StringContent("PreHttpRequesterMiddleware")});
+                }
+            };
+
+            this.Given(x => x.GivenThereIsAServiceRunningOn("http://localhost:41879", 200))
+                .And(x => x.GivenThereIsAConfiguration(new YamlConfiguration
+                {
+                    ReRoutes = new List<YamlReRoute>
+                    {
+                        new YamlReRoute
+                        {
+                            DownstreamTemplate = "http://localhost:41879/",
+                            UpstreamTemplate = "/",
+                            UpstreamHttpMethod = "Get",
+                        }
+                    }
+                }))
+                .And(x => x.GivenTheApiGatewayIsRunning(configuration))
+                .When(x => x.WhenIGetUrlOnTheApiGateway("/"))
+                .Then(x => x.ThenTheStatusCodeShouldBe(HttpStatusCode.OK))
+                .And(x => x.ThenTheResponseBodyShouldBe("PreHttpRequesterMiddleware"))
+                .BDDfy();
+        }
+
+
+
+        /// <summary>
+        /// This is annoying cos it should be in the constructor but we need to set up the yaml file before calling startup so its a step.
+        /// </summary>
+        private void GivenTheApiGatewayIsRunning(OcelotMiddlewareConfiguration ocelotMiddlewareConfig)
+        {
+            var builder = new ConfigurationBuilder()
+                .SetBasePath(Directory.GetCurrentDirectory())
+                .AddJsonFile("appsettings.json", optional: true, reloadOnChange: true)
+                .AddYamlFile("configuration.yaml")
+                .AddEnvironmentVariables();
+
+            var configuration = builder.Build();
+
+            _server = new TestServer(new WebHostBuilder()
+                .UseConfiguration(configuration)
+                .ConfigureServices(s =>
+                {
+                    s.AddOcelotYamlConfiguration(configuration);
+                    s.AddOcelot();
+                })
+                .ConfigureLogging(l =>
+                {
+                    l.AddConsole(configuration.GetSection("Logging"));
+                    l.AddDebug();
+                })
+                .Configure(a =>
+                {
+                    a.UseOcelot(ocelotMiddlewareConfig);
+                }));
+                
+            _client = _server.CreateClient();
+        }
+
+        private void GivenThereIsAConfiguration(YamlConfiguration yamlConfiguration)
+        {
+            var serializer = new Serializer();
+
+            if (File.Exists(_configurationPath))
+            {
+                File.Delete(_configurationPath);
+            }
+
+            using (TextWriter writer = File.CreateText(_configurationPath))
+            {
+                serializer.Serialize(writer, yamlConfiguration);
+            }
+        }
+
+        private void GivenThereIsAServiceRunningOn(string url, int statusCode)
+        {
+            _builder = new WebHostBuilder()
+                .UseUrls(url)
+                .UseKestrel()
+                .UseContentRoot(Directory.GetCurrentDirectory())
+                .UseIISIntegration()
+                .UseUrls(url)
+                .Configure(app =>
+                {
+                    app.Run(async context =>
+                    {
+                        context.Response.StatusCode = statusCode;
+                    });
+                })
+                .Build();
+
+            _builder.Start();
+        }
+
+        private void WhenIGetUrlOnTheApiGateway(string url)
+        {
+            _response = _client.GetAsync(url).Result;
+        }
+
+        private void ThenTheStatusCodeShouldBe(HttpStatusCode expectedHttpStatusCode)
+        {
+            _response.StatusCode.ShouldBe(expectedHttpStatusCode);
+        }
+
+        private void ThenTheResponseBodyShouldBe(string expectedBody)
+        {
+            _response.Content.ReadAsStringAsync().Result.ShouldBe(expectedBody);
+        }
+
+        public void Dispose()
+        {
+            _builder?.Dispose();
+            _client.Dispose();
+            _server.Dispose();
+        }
+    }
+}

test/Ocelot.AcceptanceTests/configuration.yaml

@@ -1,13 +1,7 @@
 ReRoutes:
-- DownstreamTemplate: http://localhost:51876/
+- DownstreamTemplate: http://localhost:41879/
   UpstreamTemplate: /
-  UpstreamHttpMethod: Post
+  UpstreamHttpMethod: Get
-  AuthenticationOptions:
+  AddHeadersToRequest: {}
-    Provider: IdentityServer
+  AddClaimsToRequest: {}
-    ProviderRootUrl: http://localhost:51888
+  RouteClaimsRequirement: {}
-    ScopeName: api
-    AdditionalScopes: []
-    ScopeSecret: secret
-  ProxyRequestHeaders:
-	- CustomerId: Claims[CustomerId]
-

test/Ocelot.AcceptanceTests/project.json

@@ -4,7 +4,7 @@
   "buildOptions": {
     "copyToOutput": {
         "include": [
-            "configuration.yaml"
+            "middlewareConfiguration.yaml"
         ]
     }
   },

test/Ocelot.ManualTest/project.json

@@ -39,7 +39,7 @@
         "preserveCompilationContext": true,
         "copyToOutput": {
             "include": [
-                "configuration.yaml"
+                "middlewareConfiguration.yaml"
             ]
         }
         },
@@ -57,7 +57,7 @@
                 "Areas/**/Views",
                 "appsettings.json",
                 "web.config",
-                "configuration.yaml"
+                "middlewareConfiguration.yaml"
             ]
         },
 

test/Ocelot.ManualTest/web.config

@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
-<configuration>
+<middlewareConfiguration>
 
   <!--
     Configure your application settings in appsettings.json. Learn more at http://go.microsoft.com/fwlink/?LinkId=786380
@@ -11,4 +11,4 @@
     </handlers>
     <aspNetCore processPath="%LAUNCHER_PATH%" arguments="%LAUNCHER_ARGS%" stdoutLogEnabled="false" stdoutLogFile=".\logs\stdout" forwardWindowsAuthToken="false"/>
   </system.webServer>
-</configuration>
+</middlewareConfiguration>

test/Ocelot.UnitTests/Configuration/YamlConfigurationProviderTests.cs

@@ -26,7 +26,7 @@ namespace Ocelot.UnitTests.Configuration
         {
             _creator = new Mock<IOcelotConfigurationCreator>();
             _configurationRepository = new Mock<IOcelotConfigurationRepository>();
-            _ocelotConfigurationProvider = new YamlOcelotConfigurationProvider(_configurationRepository.Object, _creator.Object);
+            _ocelotConfigurationProvider = new OcelotConfigurationProvider(_configurationRepository.Object, _creator.Object);
         }
 
         [Fact]