feature written, tests passed

ThreeMammals#1672

src/Ocelot/Configuration/Builder/DownstreamRouteBuilder.cs

@@ -44,6 +44,7 @@ public class DownstreamRouteBuilder
     private SecurityOptions _securityOptions;
     private string _downstreamHttpMethod;
     private Version _downstreamHttpVersion;
+    private HttpVersionPolicy _downstreamVersionPolicy;
 
     public DownstreamRouteBuilder()
     {
@@ -263,6 +264,12 @@ public DownstreamRouteBuilder WithDownstreamHttpVersion(Version downstreamHttpVe
         return this;
     }
 
+    public DownstreamRouteBuilder WithDownstreamPolicyBuilder(HttpVersionPolicy downstreamVersionPolicy)
+    {
+        _downstreamVersionPolicy = downstreamVersionPolicy;
+        return this;
+    }
+
     public DownstreamRoute Build()
     {
         return new DownstreamRoute(
@@ -299,6 +306,7 @@ public DownstreamRoute Build()
             _dangerousAcceptAnyServerCertificateValidator,
             _securityOptions,
             _downstreamHttpMethod,
-            _downstreamHttpVersion);
+            _downstreamHttpVersion,
+            _downstreamVersionPolicy);
     }
 }

src/Ocelot/Configuration/Creator/IVersionPolicyCreator.cs

@@ -0,0 +1,14 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Net.Http;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace Ocelot.Configuration.Creator
+{
+    public interface IVersionPolicyCreator
+    {
+        HttpVersionPolicy Create(string downstreamVersionPolicy);
+    }
+}

src/Ocelot/Configuration/Creator/RoutesCreator.cs

@@ -26,6 +26,7 @@ public class RoutesCreator : IRoutesCreator
         private readonly IRouteKeyCreator _routeKeyCreator;
         private readonly ISecurityOptionsCreator _securityOptionsCreator;
         private readonly IVersionCreator _versionCreator;
+        private readonly IVersionPolicyCreator _versionPolicyCreator;
 
         public RoutesCreator(
             IClaimsToThingCreator claimsToThingCreator,
@@ -42,7 +43,8 @@ public RoutesCreator(
             ILoadBalancerOptionsCreator loadBalancerOptionsCreator,
             IRouteKeyCreator routeKeyCreator,
             ISecurityOptionsCreator securityOptionsCreator,
-            IVersionCreator versionCreator
+            IVersionCreator versionCreator,
+            IVersionPolicyCreator versionPolicyCreator
             )
         {
             _routeKeyCreator = routeKeyCreator;
@@ -61,6 +63,7 @@ IVersionCreator versionCreator
             _loadBalancerOptionsCreator = loadBalancerOptionsCreator;
             _securityOptionsCreator = securityOptionsCreator;
             _versionCreator = versionCreator;
+            _versionPolicyCreator = versionPolicyCreator;
         }
 
         public List<Route> Create(FileConfiguration fileConfiguration)
@@ -111,6 +114,8 @@ private DownstreamRoute SetUpDownstreamRoute(FileRoute fileRoute, FileGlobalConf
             var securityOptions = _securityOptionsCreator.Create(fileRoute.SecurityOptions);
 
             var downstreamHttpVersion = _versionCreator.Create(fileRoute.DownstreamHttpVersion);
+
+            var downstreamVersionPolicy = _versionPolicyCreator.Create(fileRoute.DownstreamVersionPolicy);
 
             var route = new DownstreamRouteBuilder()
                 .WithKey(fileRoute.Key)
@@ -147,6 +152,7 @@ private DownstreamRoute SetUpDownstreamRoute(FileRoute fileRoute, FileGlobalConf
                 .WithDangerousAcceptAnyServerCertificateValidator(fileRoute.DangerousAcceptAnyServerCertificateValidator)
                 .WithSecurityOptions(securityOptions)
                 .WithDownstreamHttpVersion(downstreamHttpVersion)
+                .WithDownstreamPolicyBuilder(downstreamVersionPolicy)
                 .WithDownStreamHttpMethod(fileRoute.DownstreamHttpMethod)
                 .Build();
 

src/Ocelot/Configuration/Creator/VersionPolicyCreator.cs

@@ -0,0 +1,18 @@
+using System.Net.Http;
+
+namespace Ocelot.Configuration.Creator
+{
+    public class VersionPolicyCreator : IVersionPolicyCreator
+    {
+        public HttpVersionPolicy Create(string downstreamVersionPolicy)
+        {
+            return downstreamVersionPolicy switch
+            {
+                "exact" => HttpVersionPolicy.RequestVersionExact,
+                "upgradeable" => HttpVersionPolicy.RequestVersionOrHigher,
+                "downgradeable" => HttpVersionPolicy.RequestVersionOrLower,
+                _ => HttpVersionPolicy.RequestVersionOrLower,
+            };
+        }
+    }
+}

src/Ocelot/Configuration/DownstreamRoute.cs

@@ -1,6 +1,6 @@
 using System;
 using System.Collections.Generic;
-
+using System.Net.Http;
 using Ocelot.Configuration.Creator;
 
 using Ocelot.Values;
@@ -43,7 +43,8 @@ public DownstreamRoute(
             bool dangerousAcceptAnyServerCertificateValidator,
             SecurityOptions securityOptions,
             string downstreamHttpMethod,
-            Version downstreamHttpVersion)
+            Version downstreamHttpVersion,
+            HttpVersionPolicy downstreamVersionPolicy)
         {
             DangerousAcceptAnyServerCertificateValidator = dangerousAcceptAnyServerCertificateValidator;
             AddHeadersToDownstream = addHeadersToDownstream;
@@ -79,6 +80,7 @@ public DownstreamRoute(
             SecurityOptions = securityOptions;
             DownstreamHttpMethod = downstreamHttpMethod;
             DownstreamHttpVersion = downstreamHttpVersion;
+            DownstreamVersionPolicy = downstreamVersionPolicy;
         }
 
         public string Key { get; }
@@ -114,6 +116,7 @@ public DownstreamRoute(
         public bool DangerousAcceptAnyServerCertificateValidator { get; }
         public SecurityOptions SecurityOptions { get; }
         public string DownstreamHttpMethod { get; }
-        public Version DownstreamHttpVersion { get; }
+        public Version DownstreamHttpVersion { get; }
+        public HttpVersionPolicy DownstreamVersionPolicy { get; }
     }
 }

src/Ocelot/Configuration/File/FileRoute.cs

@@ -57,5 +57,6 @@ public FileRoute()
         public bool DangerousAcceptAnyServerCertificateValidator { get; set; }
         public FileSecurityOptions SecurityOptions { get; set; }
         public string DownstreamHttpVersion { get; set; }
+        public string DownstreamVersionPolicy { get; set; }
     }
 }

src/Ocelot/Configuration/Validator/RouteFluentValidator.cs

@@ -91,6 +91,11 @@ public RouteFluentValidator(IAuthenticationSchemeProvider authenticationSchemePr
             {
                 RuleFor(r => r.DownstreamHttpVersion).Matches("^[0-9]([.,][0-9]{1,1})?$");
             });
+
+            When(route => !string.IsNullOrEmpty(route.DownstreamVersionPolicy), () =>
+            {
+                RuleFor(r => r.DownstreamVersionPolicy).Matches("^(exact|upgradeable|downgradeable)$");
+            });
         }
 
         private async Task<bool> IsSupportedAuthenticationProviders(FileAuthenticationOptions authenticationOptions, CancellationToken cancellationToken)

src/Ocelot/Request/Mapper/RequestMapper.cs

@@ -29,6 +29,7 @@ public async Task<Response<HttpRequestMessage>> Map(HttpRequest request, Downstr
                     Method = MapMethod(request, downstreamRoute),
                     RequestUri = MapUri(request),
                     Version = downstreamRoute.DownstreamHttpVersion,
+                    VersionPolicy = downstreamRoute.DownstreamVersionPolicy,
                 };
 
                 MapHeaders(request, requestMessage);

src/Ocelot/Requester/HttpClientBuilder.cs

@@ -63,6 +63,8 @@ public IHttpClient Create(DownstreamRoute downstreamRoute)
             _httpClient = new HttpClient(CreateHttpMessageHandler(handler, downstreamRoute))
             {
                 Timeout = timeout,
+                DefaultRequestVersion = downstreamRoute.DownstreamHttpVersion,
+                DefaultVersionPolicy = downstreamRoute.DownstreamVersionPolicy,
             };
 
             _client = new HttpClientWrapper(_httpClient);

test/Ocelot.UnitTests/Configuration/RoutesCreatorTests.cs

@@ -9,6 +9,7 @@
 using System;
 using System.Collections.Generic;
 using System.Linq;
+using System.Net.Http;
 using TestStack.BDDfy;
 using Xunit;
 
@@ -32,6 +33,7 @@ public class RoutesCreatorTests
         private readonly Mock<IRouteKeyCreator> _rrkCreator;
         private readonly Mock<ISecurityOptionsCreator> _soCreator;
         private readonly Mock<IVersionCreator> _versionCreator;
+        private readonly Mock<IVersionPolicyCreator> _versionPolicyCreator;
         private FileConfiguration _fileConfig;
         private RouteOptions _rro;
         private string _requestId;
@@ -48,6 +50,7 @@ public class RoutesCreatorTests
         private LoadBalancerOptions _lbo;
         private List<Route> _result;
         private Version _expectedVersion;
+        private HttpVersionPolicy _expectedVersionPolicy;
 
         public RoutesCreatorTests()
         {
@@ -66,6 +69,7 @@ public RoutesCreatorTests()
             _rrkCreator = new Mock<IRouteKeyCreator>();
             _soCreator = new Mock<ISecurityOptionsCreator>();
             _versionCreator = new Mock<IVersionCreator>();
+            _versionPolicyCreator = new Mock<IVersionPolicyCreator>();
 
             _creator = new RoutesCreator(
                 _cthCreator.Object,
@@ -82,7 +86,8 @@ public RoutesCreatorTests()
                 _lboCreator.Object,
                 _rrkCreator.Object,
                 _soCreator.Object,
-                _versionCreator.Object
+                _versionCreator.Object,
+                _versionPolicyCreator.Object
                 );
         }
 
@@ -160,6 +165,7 @@ private void ThenTheDependenciesAreCalledCorrectly()
         private void GivenTheDependenciesAreSetUpCorrectly()
         {
             _expectedVersion = new Version("1.1");
+            _expectedVersionPolicy = HttpVersionPolicy.RequestVersionOrLower;
             _rro = new RouteOptions(false, false, false, false, false);
             _requestId = "testy";
             _rrk = "besty";
@@ -188,6 +194,7 @@ private void GivenTheDependenciesAreSetUpCorrectly()
             _daCreator.Setup(x => x.Create(It.IsAny<FileRoute>())).Returns(_dhp);
             _lboCreator.Setup(x => x.Create(It.IsAny<FileLoadBalancerOptions>())).Returns(_lbo);
             _versionCreator.Setup(x => x.Create(It.IsAny<string>())).Returns(_expectedVersion);
+            _versionPolicyCreator.Setup(x => x.Create(It.IsAny<string>())).Returns(_expectedVersionPolicy);
         }
 
         private void ThenTheRoutesAreCreated()
@@ -216,6 +223,7 @@ private void WhenICreate()
         private void ThenTheRouteIsSet(FileRoute expected, int routeIndex)
         {
             _result[routeIndex].DownstreamRoute[0].DownstreamHttpVersion.ShouldBe(_expectedVersion);
+            _result[routeIndex].DownstreamRoute[0].DownstreamVersionPolicy.ShouldBe(_expectedVersionPolicy);
             _result[routeIndex].DownstreamRoute[0].IsAuthenticated.ShouldBe(_rro.IsAuthenticated);
             _result[routeIndex].DownstreamRoute[0].IsAuthorized.ShouldBe(_rro.IsAuthorized);
             _result[routeIndex].DownstreamRoute[0].IsCached.ShouldBe(_rro.IsCached);

test/Ocelot.UnitTests/Configuration/VersionPolicyCreatorTests.cs

@@ -0,0 +1,62 @@
+using Ocelot.Configuration.Creator;
+using System.Net.Http;
+using Shouldly;
+using TestStack.BDDfy;
+using Xunit;
+
+namespace Ocelot.UnitTests.Configuration
+{
+    public class VersionPolicyCreatorTests
+    {
+        private readonly VersionPolicyCreator _creator;
+        private string _input;
+        private HttpVersionPolicy _result;
+
+        public VersionPolicyCreatorTests()
+        {
+            _creator = new VersionPolicyCreator();
+        }
+
+        [Fact]
+        public void should_create_version_policy_based_on_input()
+        {
+            this.Given(_ => GivenTheInput("upgradeable"))
+                .When(_ => WhenICreate())
+                .Then(_ => ThenTheResultIs(HttpVersionPolicy.RequestVersionOrHigher))
+                .BDDfy();
+        }
+
+        [Fact]
+        public void should_default_to_request_version_or_lower()
+        {
+            this.Given(_ => GivenTheInput(string.Empty))
+                .When(_ => WhenICreate())
+                .Then(_ => ThenTheResultIs(HttpVersionPolicy.RequestVersionOrLower))
+                .BDDfy();
+        }
+
+        [Fact]
+        public void should_default_to_request_version_or_lower_when_setting_gibberish()
+        {
+            this.Given(_ => GivenTheInput("string is gibberish"))
+                .When(_ => WhenICreate())
+                .Then(_ => ThenTheResultIs(HttpVersionPolicy.RequestVersionOrLower))
+                .BDDfy();
+        }
+
+        private void GivenTheInput(string input)
+        {
+            _input = input;
+        }
+
+        private void WhenICreate()
+        {
+            _result = _creator.Create(_input);
+        }
+
+        private void ThenTheResultIs(HttpVersionPolicy result)
+        {
+            _result.ShouldBe(result);
+        }
+    }
+}