Feature/automatic routes with sd (#351)

* #340 started looking at supporting automatic routing when using service discovery

* #340 getting old routing tests to pass

* #340 renamed stuff to provider rather than finder, as its not longer finding anything

* #340 working towards supporting dynamic routing

* #340 loads of refactoring to make configuration work with dynamic routing

* #340 refactor consul config code so the registry class owns it

* #340 default to consul to maintain backwards compat

* #340 added docs, finished this branches todos

docs/features/routing.rst

@@ -177,4 +177,11 @@ and
     }
 
 In the example above if you make a request into Ocelot on /goods/delete Ocelot will match /goods/delete ReRoute. Previously it would have
-matched /goods/{catchAll} (because this is the first ReRoute in the list!).
+matched /goods/{catchAll} (because this is the first ReRoute in the list!).
+
+Dynamic Routing
+^^^^^^^^^^^^^^^
+
+This feature was requested in `issue 340 <https://github.com/TomPallister/Ocelot/issue/340>`_. The idea is to enable dynamic routing 
+when using a service discovery provider so you don't have to provide the ReRoute config. See the docs :ref:`service-discovery` if 
+this sounds interesting to you.

docs/features/servicediscovery.rst

@@ -1,3 +1,5 @@
+.. service-discovery:
+
 Service Discovery
 =================
 
@@ -88,3 +90,65 @@ Eureka. One of the services polls Eureka every 30 seconds (default) and gets the
 When Ocelot asks for a given service it is retrieved from memory so performance is not a big problem. Please note that this code
 is provided by the Pivotal.Discovery.Client NuGet package so big thanks to them for all the hard work.
 
+Dynamic Routing
+^^^^^^^^^^^^^^^
+
+This feature was requested in `issue 340 <https://github.com/TomPallister/Ocelot/issue/340>`_. The idea is to enable dynamic routing when using 
+a service discovery provider (see that section of the docs for more info). In this mode Ocelot will use the first segmentof the upstream path to lookup the
+downstream service with the service discovery provider. 
+
+An example of this would be calling ocelot with a url like https://api.mywebsite.com/product/products. Ocelot will take the first segment of 
+the path which is product and use it as a key to look up the service in consul. If consul returns a service Ocelot will request it on whatever host and
+port comes back from consul plus the remaining path segments in this case products thus making the downstream call http://hostfromconsul:portfromconsul/products. 
+Ocelot will apprend any query string to the downstream url as normal.
+
+In order to enable dynamic routing you need to have 0 ReRoutes in your config. At the moment you cannot mix dynamic and configuration ReRoutes. In addition to this you
+need to specify the Service Discovery provider details as outlined above and the downstream http/https scheme as DownstreamScheme.
+
+In addition to that you can set RateLimitOptions, QoSOptions, LoadBalancerOptions and HttpHandlerOptions, DownstreamScheme (You might want to call Ocelot on https but 
+talk to private services over http) that will be applied to all of the dynamic ReRoutes.
+
+The config might look something like 
+
+.. code-block:: json
+
+    {
+        "ReRoutes": [],
+        "Aggregates": [],
+        "GlobalConfiguration": {
+            "RequestIdKey": null,
+            "ServiceDiscoveryProvider": {
+                "Host": "localhost",
+                "Port": 8510,
+                "Type": null,
+                "Token": null,
+                "ConfigurationKey": null
+            },
+            "RateLimitOptions": {
+                "ClientIdHeader": "ClientId",
+                "QuotaExceededMessage": null,
+                "RateLimitCounterPrefix": "ocelot",
+                "DisableRateLimitHeaders": false,
+                "HttpStatusCode": 429
+            },
+            "QoSOptions": {
+                "ExceptionsAllowedBeforeBreaking": 0,
+                "DurationOfBreak": 0,
+                "TimeoutValue": 0
+            },
+            "BaseUrl": null,
+                "LoadBalancerOptions": {
+                "Type": "LeastConnection",
+                "Key": null,
+                "Expiry": 0
+            },
+            "DownstreamScheme": "http",
+            "HttpHandlerOptions": {
+                "AllowAutoRedirect": false,
+                "UseCookieContainer": false,
+                "UseTracing": false
+            }
+        }
+    }
+
+Please take a look through all of the docs to understand these options.

src/Ocelot/Configuration/Builder/DownstreamReRouteBuilder.cs

@@ -9,7 +9,7 @@ namespace Ocelot.Configuration.Builder
     public class DownstreamReRouteBuilder
     {
         private AuthenticationOptions _authenticationOptions;
-        private string _reRouteKey;
+        private string _loadBalancerKey;
         private string _downstreamPathTemplate;
         private string _upstreamTemplate;
         private UpstreamPathTemplate _upstreamTemplatePattern;
@@ -25,7 +25,6 @@ public class DownstreamReRouteBuilder
         private CacheOptions _fileCacheOptions;
         private string _downstreamScheme;
         private LoadBalancerOptions _loadBalancerOptions;
-        private bool _useQos;
         private QoSOptions _qosOptions;
         private HttpHandlerOptions _httpHandlerOptions;
         private bool _enableRateLimiting;
@@ -41,7 +40,6 @@ public class DownstreamReRouteBuilder
         private List<AddHeader> _addHeadersToDownstream;
         private List<AddHeader> _addHeadersToUpstream;
         private bool _dangerousAcceptAnyServerCertificateValidator;
-        private string _qosKey;
 
         public DownstreamReRouteBuilder()
         {
@@ -153,27 +151,15 @@ public DownstreamReRouteBuilder WithCacheOptions(CacheOptions input)
             return this;
         }
 
-        public DownstreamReRouteBuilder WithIsQos(bool input)
-        {
-            _useQos = input;
-            return this;
-        }
-
         public DownstreamReRouteBuilder WithQosOptions(QoSOptions input)
         {
             _qosOptions = input;
             return this;
         }
 
-        public DownstreamReRouteBuilder WithReRouteKey(string reRouteKey)
-        {
-            _reRouteKey = reRouteKey;
-            return this;
-        }
-
-        public DownstreamReRouteBuilder WithQosKey(string qosKey)
+        public DownstreamReRouteBuilder WithLoadBalancerKey(string loadBalancerKey)
         {
-            _qosKey = qosKey;
+            _loadBalancerKey = loadBalancerKey;
             return this;
         }
 
@@ -267,7 +253,6 @@ public DownstreamReRoute Build()
                 _httpHandlerOptions, 
                 _useServiceDiscovery, 
                 _enableRateLimiting, 
-                _useQos, 
                 _qosOptions,
                 _downstreamScheme, 
                 _requestIdHeaderKey, 
@@ -283,12 +268,11 @@ public DownstreamReRoute Build()
                 _isAuthorised, 
                 _authenticationOptions, 
                 new PathTemplate(_downstreamPathTemplate),
-                _reRouteKey,
+                _loadBalancerKey,
                 _delegatingHandlers,
                 _addHeadersToDownstream,
                 _addHeadersToUpstream,
-                _dangerousAcceptAnyServerCertificateValidator,
-                _qosKey);
+                _dangerousAcceptAnyServerCertificateValidator);
         }
     }
 }

src/Ocelot/Configuration/Builder/QoSOptionsBuilder.cs

@@ -6,7 +6,9 @@ public class QoSOptionsBuilder
 
         private int _durationOfBreak;
 
-        private int _timeoutValue;
+        private int _timeoutValue;
+
+        private string _key;
 
         public QoSOptionsBuilder WithExceptionsAllowedBeforeBreaking(int exceptionsAllowedBeforeBreaking)
         {
@@ -26,9 +28,15 @@ public QoSOptionsBuilder WithTimeoutValue(int timeoutValue)
             return this;
         }
 
+        public QoSOptionsBuilder WithKey(string input)
+        {
+            _key = input;
+            return this;
+        }
+
         public QoSOptions Build()
         {
-            return new QoSOptions(_exceptionsAllowedBeforeBreaking, _durationOfBreak, _timeoutValue);
+            return new QoSOptions(_exceptionsAllowedBeforeBreaking, _durationOfBreak, _timeoutValue, _key);
         }
     }
 }

src/Ocelot/Configuration/Builder/ReRouteOptionsBuilder.cs

@@ -5,7 +5,6 @@ public class ReRouteOptionsBuilder
         private bool _isAuthenticated;
         private bool _isAuthorised;
         private bool _isCached;
-        private bool _isQoS;
         private bool _enableRateLimiting;
 
         public ReRouteOptionsBuilder WithIsCached(bool isCached)
@@ -26,12 +25,6 @@ public ReRouteOptionsBuilder WithIsAuthorised(bool isAuthorised)
             return this;
         }
 
-        public ReRouteOptionsBuilder WithIsQos(bool isQoS)
-        {
-            _isQoS = isQoS;
-            return this;
-        }
-
         public ReRouteOptionsBuilder WithRateLimiting(bool enableRateLimiting)
         {
             _enableRateLimiting = enableRateLimiting;
@@ -40,7 +33,7 @@ public ReRouteOptionsBuilder WithRateLimiting(bool enableRateLimiting)
 
         public ReRouteOptions Build()
         {
-            return new ReRouteOptions(_isAuthenticated, _isAuthorised, _isCached, _isQoS, _enableRateLimiting);
+            return new ReRouteOptions(_isAuthenticated, _isAuthorised, _isCached, _enableRateLimiting);
         }
     }
-}
+}

src/Ocelot/Configuration/Creator/FileInternalConfigurationCreator.cs

@@ -104,8 +104,22 @@ private async Task<Response<IInternalConfiguration>> SetUpConfiguration(FileConf
             }
 
             var serviceProviderConfiguration = _serviceProviderConfigCreator.Create(fileConfiguration.GlobalConfiguration);
-
-            var config = new InternalConfiguration(reRoutes, _adminPath.Path, serviceProviderConfiguration, fileConfiguration.GlobalConfiguration.RequestIdKey);
+
+            var lbOptions = CreateLoadBalancerOptions(fileConfiguration.GlobalConfiguration.LoadBalancerOptions);
+
+            var qosOptions = _qosOptionsCreator.Create(fileConfiguration.GlobalConfiguration.QoSOptions);
+
+            var httpHandlerOptions = _httpHandlerOptionsCreator.Create(fileConfiguration.GlobalConfiguration.HttpHandlerOptions);
+
+            var config = new InternalConfiguration(reRoutes, 
+                _adminPath.Path, 
+                serviceProviderConfiguration, 
+                fileConfiguration.GlobalConfiguration.RequestIdKey, 
+                lbOptions, 
+                fileConfiguration.GlobalConfiguration.DownstreamScheme,
+                qosOptions,
+                httpHandlerOptions
+                );
 
             return new OkResponse<IInternalConfiguration>(config);
         }
@@ -160,8 +174,6 @@ private DownstreamReRoute SetUpDownstreamReRoute(FileReRoute fileReRoute, FileGl
 
             var reRouteKey = CreateReRouteKey(fileReRoute);
 
-            var qosKey = CreateQosKey(fileReRoute);
-
             var upstreamTemplatePattern = _upstreamTemplatePatternCreator.Create(fileReRoute);
 
             var authOptionsForRoute = _authOptionsCreator.Create(fileReRoute);
@@ -172,19 +184,19 @@ private DownstreamReRoute SetUpDownstreamReRoute(FileReRoute fileReRoute, FileGl
 
             var claimsToQueries = _claimsToThingCreator.Create(fileReRoute.AddQueriesToRequest);
 
-            var qosOptions = _qosOptionsCreator.Create(fileReRoute);
+            var qosOptions = _qosOptionsCreator.Create(fileReRoute.QoSOptions, fileReRoute.UpstreamPathTemplate, fileReRoute.UpstreamHttpMethod.ToArray());
 
             var rateLimitOption = _rateLimitOptionsCreator.Create(fileReRoute, globalConfiguration, fileReRouteOptions.EnableRateLimiting);
 
             var region = _regionCreator.Create(fileReRoute);
 
-            var httpHandlerOptions = _httpHandlerOptionsCreator.Create(fileReRoute);
+            var httpHandlerOptions = _httpHandlerOptionsCreator.Create(fileReRoute.HttpHandlerOptions);
 
             var hAndRs = _headerFAndRCreator.Create(fileReRoute);
 
             var downstreamAddresses = _downstreamAddressesCreator.Create(fileReRoute);
 
-            var lbOptions = CreateLoadBalancerOptions(fileReRoute);
+            var lbOptions = CreateLoadBalancerOptions(fileReRoute.LoadBalancerOptions);
 
             var reRoute = new DownstreamReRouteBuilder()
                 .WithKey(fileReRoute.Key)
@@ -205,9 +217,7 @@ private DownstreamReRoute SetUpDownstreamReRoute(FileReRoute fileReRoute, FileGl
                 .WithDownstreamScheme(fileReRoute.DownstreamScheme)
                 .WithLoadBalancerOptions(lbOptions)
                 .WithDownstreamAddresses(downstreamAddresses)
-                .WithReRouteKey(reRouteKey)
-                .WithQosKey(qosKey)
-                .WithIsQos(fileReRouteOptions.IsQos)
+                .WithLoadBalancerKey(reRouteKey)
                 .WithQosOptions(qosOptions)
                 .WithEnableRateLimiting(fileReRouteOptions.EnableRateLimiting)
                 .WithRateLimitOptions(rateLimitOption)
@@ -226,9 +236,13 @@ private DownstreamReRoute SetUpDownstreamReRoute(FileReRoute fileReRoute, FileGl
             return reRoute;
         }
 
-        private LoadBalancerOptions CreateLoadBalancerOptions(FileReRoute fileReRoute)
+        private LoadBalancerOptions CreateLoadBalancerOptions(FileLoadBalancerOptions options)
         {
-            return new LoadBalancerOptions(fileReRoute.LoadBalancerOptions.Type, fileReRoute.LoadBalancerOptions.Key, fileReRoute.LoadBalancerOptions.Expiry);
+            return new LoadBalancerOptionsBuilder()
+                .WithType(options.Type)
+                .WithKey(options.Key)
+                .WithExpiryInMs(options.Expiry)
+                .Build();
         }
 
         private string CreateReRouteKey(FileReRoute fileReRoute)
@@ -238,14 +252,7 @@ private string CreateReRouteKey(FileReRoute fileReRoute)
                 return $"{nameof(CookieStickySessions)}:{fileReRoute.LoadBalancerOptions.Key}";
             }
 
-            return CreateQosKey(fileReRoute);
-        }
-
-        private string CreateQosKey(FileReRoute fileReRoute)
-        {
-            //note - not sure if this is the correct key, but this is probably the only unique key i can think of given my poor brain
-            var loadBalancerKey = $"{fileReRoute.UpstreamPathTemplate}|{string.Join(",", fileReRoute.UpstreamHttpMethod)}";
-            return loadBalancerKey;
+            return $"{fileReRoute.UpstreamPathTemplate}|{string.Join(",", fileReRoute.UpstreamHttpMethod)}";
         }
     }
 }

src/Ocelot/Configuration/Creator/HttpHandlerOptionsCreator.cs

@@ -6,19 +6,19 @@ namespace Ocelot.Configuration.Creator
 {
     public class HttpHandlerOptionsCreator : IHttpHandlerOptionsCreator
     {
-        private IServiceTracer _tracer;
+        private readonly IServiceTracer _tracer;
 
         public HttpHandlerOptionsCreator(IServiceTracer tracer)
         {
             _tracer = tracer;
         }
 
-        public HttpHandlerOptions Create(FileReRoute fileReRoute)
+        public HttpHandlerOptions Create(FileHttpHandlerOptions options)
         {
-            var useTracing = _tracer.GetType() != typeof(FakeServiceTracer) ? fileReRoute.HttpHandlerOptions.UseTracing : false;
+            var useTracing = _tracer.GetType() != typeof(FakeServiceTracer) && options.UseTracing;
 
-            return new HttpHandlerOptions(fileReRoute.HttpHandlerOptions.AllowAutoRedirect,
-                fileReRoute.HttpHandlerOptions.UseCookieContainer, useTracing);
+            return new HttpHandlerOptions(options.AllowAutoRedirect,
+                options.UseCookieContainer, useTracing);
         }
     }
 }

src/Ocelot/Configuration/Creator/IHttpHandlerOptionsCreator.cs

@@ -7,6 +7,6 @@ namespace Ocelot.Configuration.Creator
     /// </summary>
     public interface IHttpHandlerOptionsCreator
     {
-        HttpHandlerOptions Create(FileReRoute fileReRoute);
+        HttpHandlerOptions Create(FileHttpHandlerOptions fileReRoute);
     }
 }

src/Ocelot/Configuration/Creator/IQoSOptionsCreator.cs

@@ -4,6 +4,8 @@ namespace Ocelot.Configuration.Creator
 {
     public interface IQoSOptionsCreator
     {
-        QoSOptions Create(FileReRoute fileReRoute);
+        QoSOptions Create(FileQoSOptions options);
+        QoSOptions Create(FileQoSOptions options, string pathTemplate, string[] httpMethods);
+        QoSOptions Create(QoSOptions options, string pathTemplate, string[] httpMethods);
     }
-}
+}

src/Ocelot/Configuration/Creator/IReRouteOptionsCreator.cs

@@ -6,4 +6,4 @@ public interface IReRouteOptionsCreator
     {
         ReRouteOptions Create(FileReRoute fileReRoute);
     }
-}
+}