Reload config on change (#527)

* Reload config on change.
Added test case.

* added testing for adding the json with reloadOnChange = false

src/Ocelot/Middleware/OcelotMiddlewareExtensions.cs

@@ -113,12 +113,12 @@
         {
             // make configuration from file system?
             // earlier user needed to add ocelot files in startup configuration stuff, asp.net will map it to this
-            var fileConfig = builder.ApplicationServices.GetService<IOptions<FileConfiguration>>();
+            var fileConfig = builder.ApplicationServices.GetService<IOptionsMonitor<FileConfiguration>>();
 
             // now create the config
             var internalConfigCreator = builder.ApplicationServices.GetService<IInternalConfigurationCreator>();
-            var internalConfig = await internalConfigCreator.Create(fileConfig.Value);
+            var internalConfig = await internalConfigCreator.Create(fileConfig.CurrentValue);
-           //Configuration error, throw error message
+            //Configuration error, throw error message
             if (internalConfig.IsError)
             {
                 ThrowToStopOcelotStarting(internalConfig);
@@ -128,6 +128,12 @@
             var internalConfigRepo = builder.ApplicationServices.GetService<IInternalConfigurationRepository>();
             internalConfigRepo.AddOrReplace(internalConfig.Data);
 
+            fileConfig.OnChange(async (config) =>
+            {
+                var newInternalConfig = await internalConfigCreator.Create(config);
+                internalConfigRepo.AddOrReplace(newInternalConfig.Data);
+            });
+
             var fileConfigRepo = builder.ApplicationServices.GetService<IFileConfigurationRepository>();
 
             var adminPath = builder.ApplicationServices.GetService<IAdministrationPath>();
@@ -155,7 +161,7 @@
         }
 
         private static async Task SetFileConfigInConsul(IApplicationBuilder builder,
-            IFileConfigurationRepository fileConfigRepo, IOptions<FileConfiguration> fileConfig,
+            IFileConfigurationRepository fileConfigRepo, IOptionsMonitor<FileConfiguration> fileConfig,
             IInternalConfigurationCreator internalConfigCreator, IInternalConfigurationRepository internalConfigRepo)
         {
             // get the config from consul.
@@ -168,7 +174,7 @@
             else if (ConfigNotStoredInConsul(fileConfigFromConsul))
             {
                 //there was no config in consul set the file in config in consul
-                await fileConfigRepo.Set(fileConfig.Value);
+                await fileConfigRepo.Set(fileConfig.CurrentValue);
             }
             else
             {
@@ -197,9 +203,9 @@
             }
         }
 
-        private static async Task SetFileConfig(IFileConfigurationSetter fileConfigSetter, IOptions<FileConfiguration> fileConfig)
+        private static async Task SetFileConfig(IFileConfigurationSetter fileConfigSetter, IOptionsMonitor<FileConfiguration> fileConfig)
         {
-            var response = await fileConfigSetter.Set(fileConfig.Value);
+            var response = await fileConfigSetter.Set(fileConfig.CurrentValue);
 
             if (IsError(response))
             {

test/Ocelot.AcceptanceTests/ConfigurationReloadTests.cs

@@ -0,0 +1,68 @@
+using Ocelot.Configuration.File;
+using Ocelot.Configuration.Setter;
+using Ocelot.Middleware;
+using Shouldly;
+using System;
+using System.Collections.Generic;
+using System.Text;
+using TestStack.BDDfy;
+using Xunit;
+
+namespace Ocelot.AcceptanceTests
+{
+    public class ConfigurationReloadTests : IDisposable
+    {
+        private FileConfiguration _initialConfig;
+        private FileConfiguration _anotherConfig;
+        private Steps _steps;
+
+        public ConfigurationReloadTests()
+        {
+            _steps = new Steps();
+
+            _initialConfig = new FileConfiguration
+            {
+                GlobalConfiguration = new FileGlobalConfiguration
+                {
+                    RequestIdKey = "initialKey"
+                }
+            };
+
+            _anotherConfig = new FileConfiguration
+            {
+                GlobalConfiguration = new FileGlobalConfiguration
+                {
+                    RequestIdKey = "someOtherKey"
+                }
+            };
+        }
+
+        [Fact]
+        public void should_reload_config_on_change()
+        {           
+            this.Given(x => _steps.GivenThereIsAConfiguration(_initialConfig))
+                .And(x => _steps.GivenOcelotIsRunningReloadingConfig(true))
+                .And(x => _steps.GivenThereIsAConfiguration(_anotherConfig))
+                .And(x => _steps.GivenIWait(2500))
+                .And(x => _steps.ThenConfigShouldBe(_anotherConfig))
+                .BDDfy();
+        }
+
+        [Fact]
+        public void should_not_reload_config_on_change()
+        {
+           
+            this.Given(x => _steps.GivenThereIsAConfiguration(_initialConfig))
+                .And(x => _steps.GivenOcelotIsRunningReloadingConfig(false))
+                .And(x => _steps.GivenThereIsAConfiguration(_anotherConfig))
+                .And(x => _steps.GivenIWait(2500))
+                .And(x => _steps.ThenConfigShouldBe(_initialConfig))
+                .BDDfy();
+        }
+
+        public void Dispose()
+        {
+            _steps.Dispose();
+        }
+    }
+}

test/Ocelot.AcceptanceTests/Steps.cs

@@ -34,6 +34,7 @@ namespace Ocelot.AcceptanceTests
     using Butterfly;
     using Configuration.Repository;
     using Microsoft.Net.Http.Headers;
+    using Ocelot.Configuration.Creator;
     using MediaTypeHeaderValue = System.Net.Http.Headers.MediaTypeHeaderValue;
 
     public class Steps : IDisposable
@@ -55,6 +56,18 @@ namespace Ocelot.AcceptanceTests
             _random = new Random();
         }
 
+        public async Task ThenConfigShouldBe(FileConfiguration fileConfig)
+        {
+            var internalConfigCreator = _ocelotServer.Host.Services.GetService<IInternalConfigurationCreator>();
+
+            var internalConfigRepo = _ocelotServer.Host.Services.GetService<IInternalConfigurationRepository>();
+            var internalConfig = internalConfigRepo.Get();
+
+            var config = await internalConfigCreator.Create(fileConfig);
+
+            internalConfig.Data.RequestId.ShouldBe(config.Data.RequestId);
+        }
+
         public async Task StartFakeOcelotWithWebSockets()
         {
             _ocelotBuilder = new WebHostBuilder();
@@ -116,6 +129,34 @@ namespace Ocelot.AcceptanceTests
             File.WriteAllText(configurationPath, jsonConfiguration);
         }
 
+        public void GivenOcelotIsRunningReloadingConfig(bool shouldReload)
+        {
+            _webHostBuilder = new WebHostBuilder();
+
+            _webHostBuilder
+                .ConfigureAppConfiguration((hostingContext, config) =>
+                {
+                    config.SetBasePath(hostingContext.HostingEnvironment.ContentRootPath);
+                    var env = hostingContext.HostingEnvironment;
+                    config.AddJsonFile("appsettings.json", optional: true, reloadOnChange: false)
+                        .AddJsonFile($"appsettings.{env.EnvironmentName}.json", optional: true, reloadOnChange: false);
+                    config.AddJsonFile("ocelot.json", optional: false, reloadOnChange: shouldReload);
+                    config.AddEnvironmentVariables();
+                })
+                .ConfigureServices(s =>
+                {
+                    s.AddOcelot();                    
+                })
+                .Configure(app =>
+                {
+                    app.UseOcelot().Wait();
+                });
+
+            _ocelotServer = new TestServer(_webHostBuilder);
+
+            _ocelotClient = _ocelotServer.CreateClient();
+        }
+
         /// <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>