Rewire LoadBalancerFactory to allow injecting custom load balancers, by introducing LoadBalancerCreators

2025-11-04 22:30:50 +08:00 · 2019-07-10 19:15:17 +02:00
parent c73cf59908
commit de012a0794
14 changed files with 521 additions and 77 deletions
--- a/test/Ocelot.UnitTests/DependencyInjection/OcelotBuilderTests.cs
+++ b/test/Ocelot.UnitTests/DependencyInjection/OcelotBuilderTests.cs
@@ -1,3 +1,7 @@
+using Ocelot.Configuration;
+using Ocelot.LoadBalancer.LoadBalancers;
+using Ocelot.ServiceDiscovery.Providers;
+
 namespace Ocelot.UnitTests.DependencyInjection
 {
    using Microsoft.AspNetCore.Hosting;
@@ -158,11 +162,26 @@ namespace Ocelot.UnitTests.DependencyInjection
                .BDDfy();
        }

+        [Fact]
+        public void should_add_custom_load_balancer_creators()
+        {
+            this.Given(x => WhenISetUpOcelotServices())
+                .When(x => AddSingletonLoadBalancerCreator<FakeCustomLoadBalancerCreator>())
+                .Then(x => ThenTheProviderIsRegisteredAndReturnsBothBuiltInAndCustomLoadBalancerCreators())
+                .BDDfy();
+        }
+
        private void AddSingletonDefinedAggregator<T>()
            where T : class, IDefinedAggregator
        {
            _ocelotBuilder.AddSingletonDefinedAggregator<T>();
        }
+        
+        private void AddSingletonLoadBalancerCreator<T>()
+            where T : class, ILoadBalancerCreator
+        {
+            _ocelotBuilder.Services.AddSingleton<ILoadBalancerCreator, T>();
+        }

        private void AddTransientDefinedAggregator<T>()
            where T : class, IDefinedAggregator
@@ -238,6 +257,17 @@ namespace Ocelot.UnitTests.DependencyInjection
            handlers[0].ShouldBeOfType<TOne>();
            handlers[1].ShouldBeOfType<TWo>();
        }
+        
+        private void ThenTheProviderIsRegisteredAndReturnsBothBuiltInAndCustomLoadBalancerCreators()
+        {
+            _serviceProvider = _services.BuildServiceProvider();
+            var creators = _serviceProvider.GetServices<ILoadBalancerCreator>().ToList();
+            creators.Count(c => c.GetType() == typeof(NoLoadBalancerCreator)).ShouldBe(1);
+            creators.Count(c => c.GetType() == typeof(RoundRobinCreator)).ShouldBe(1);
+            creators.Count(c => c.GetType() == typeof(CookieStickySessionsCreator)).ShouldBe(1);
+            creators.Count(c => c.GetType() == typeof(LeastConnectionCreator)).ShouldBe(1);
+            creators.Count(c => c.GetType() == typeof(FakeCustomLoadBalancerCreator)).ShouldBe(1);
+        }

        private void ThenTheAggregatorsAreTransient<TOne, TWo>()
        {
@@ -323,5 +353,15 @@ namespace Ocelot.UnitTests.DependencyInjection
        {
            _ex.ShouldBeNull();
        }
+
+        private class FakeCustomLoadBalancerCreator : ILoadBalancerCreator
+        {
+            public ILoadBalancer Create(DownstreamReRoute reRoute, IServiceDiscoveryProvider serviceProvider)
+            {
+                throw new NotImplementedException();
+            }
+
+            public string Type { get; }
+        }
    }
 }
--- a/test/Ocelot.UnitTests/LoadBalancer/CookieStickySessionsCreatorTests.cs
+++ b/test/Ocelot.UnitTests/LoadBalancer/CookieStickySessionsCreatorTests.cs
@@ -0,0 +1,73 @@
+using Moq;
+using Ocelot.Configuration;
+using Ocelot.Configuration.Builder;
+using Ocelot.LoadBalancer.LoadBalancers;
+using Ocelot.ServiceDiscovery.Providers;
+using Shouldly;
+using TestStack.BDDfy;
+using Xunit;
+
+namespace Ocelot.UnitTests.LoadBalancer
+{
+    public class CookieStickySessionsCreatorTests
+    {
+        private readonly CookieStickySessionsCreator _creator;
+        private readonly Mock<IServiceDiscoveryProvider> _serviceProvider;
+        private DownstreamReRoute _reRoute;
+        private ILoadBalancer _loadBalancer;
+        private string _typeName;
+
+        public CookieStickySessionsCreatorTests()
+        {
+            _creator = new CookieStickySessionsCreator();
+            _serviceProvider = new Mock<IServiceDiscoveryProvider>();
+        }
+        
+        [Fact]
+        public void should_return_expected_name()
+        {
+            var reRoute = new DownstreamReRouteBuilder()
+                .WithLoadBalancerOptions(new LoadBalancerOptions("myType", "myKey", 1000))
+                .Build();
+
+            this.Given(x => x.GivenAReRoute(reRoute))
+                .When(x => x.WhenIGetTheLoadBalancer())
+                .Then(x => x.ThenTheLoadBalancerIsReturned<CookieStickySessions>())
+                .BDDfy();
+        }
+                
+        [Fact]
+        public void should_return_instance_of_expected_load_balancer_type()
+        {
+            this.When(x => x.WhenIGetTheLoadBalancerTypeName())
+                .Then(x => x.ThenTheLoadBalancerTypeIs("CookieStickySessions"))
+                .BDDfy();
+        }
+
+        private void GivenAReRoute(DownstreamReRoute reRoute)
+        {
+            _reRoute = reRoute;
+        }
+
+        private void WhenIGetTheLoadBalancer()
+        {
+            _loadBalancer = _creator.Create(_reRoute, _serviceProvider.Object);
+        }
+        
+        private void WhenIGetTheLoadBalancerTypeName()
+        {
+            _typeName = _creator.Type;
+        }
+
+        private void ThenTheLoadBalancerIsReturned<T>()
+            where T : ILoadBalancer
+        {
+            _loadBalancer.ShouldBeOfType<T>();
+        }
+
+        private void ThenTheLoadBalancerTypeIs(string type)
+        {
+            _typeName.ShouldBe(type);
+        }
+    }
+}
--- a/test/Ocelot.UnitTests/LoadBalancer/LeastConnectionCreatorTests.cs
+++ b/test/Ocelot.UnitTests/LoadBalancer/LeastConnectionCreatorTests.cs
@@ -0,0 +1,73 @@
+using Moq;
+using Ocelot.Configuration;
+using Ocelot.Configuration.Builder;
+using Ocelot.LoadBalancer.LoadBalancers;
+using Ocelot.ServiceDiscovery.Providers;
+using Shouldly;
+using TestStack.BDDfy;
+using Xunit;
+
+namespace Ocelot.UnitTests.LoadBalancer
+{
+    public class LeastConnectionCreatorTests
+    {
+        private readonly LeastConnectionCreator _creator;
+        private readonly Mock<IServiceDiscoveryProvider> _serviceProvider;
+        private DownstreamReRoute _reRoute;
+        private ILoadBalancer _loadBalancer;
+        private string _typeName;
+
+        public LeastConnectionCreatorTests()
+        {
+            _creator = new LeastConnectionCreator();
+            _serviceProvider = new Mock<IServiceDiscoveryProvider>();
+        }
+        
+        [Fact]
+        public void should_return_expected_name()
+        {
+            var reRoute = new DownstreamReRouteBuilder()
+                .WithServiceName("myService")
+                .Build();
+
+            this.Given(x => x.GivenAReRoute(reRoute))
+                .When(x => x.WhenIGetTheLoadBalancer())
+                .Then(x => x.ThenTheLoadBalancerIsReturned<LeastConnection>())
+                .BDDfy();
+        }
+                
+        [Fact]
+        public void should_return_instance_of_expected_load_balancer_type()
+        {
+            this.When(x => x.WhenIGetTheLoadBalancerTypeName())
+                .Then(x => x.ThenTheLoadBalancerTypeIs("LeastConnection"))
+                .BDDfy();
+        }
+
+        private void GivenAReRoute(DownstreamReRoute reRoute)
+        {
+            _reRoute = reRoute;
+        }
+
+        private void WhenIGetTheLoadBalancer()
+        {
+            _loadBalancer = _creator.Create(_reRoute, _serviceProvider.Object);
+        }
+        
+        private void WhenIGetTheLoadBalancerTypeName()
+        {
+            _typeName = _creator.Type;
+        }
+
+        private void ThenTheLoadBalancerIsReturned<T>()
+            where T : ILoadBalancer
+        {
+            _loadBalancer.ShouldBeOfType<T>();
+        }
+
+        private void ThenTheLoadBalancerTypeIs(string type)
+        {
+            _typeName.ShouldBe(type);
+        }
+    }
+}
--- a/test/Ocelot.UnitTests/LoadBalancer/LoadBalancerFactoryTests.cs
+++ b/test/Ocelot.UnitTests/LoadBalancer/LoadBalancerFactoryTests.cs
@@ -7,6 +7,9 @@ using Ocelot.ServiceDiscovery;
 using Ocelot.ServiceDiscovery.Providers;
 using Shouldly;
 using System.Collections.Generic;
+using System.Threading.Tasks;
+using Ocelot.Middleware;
+using Ocelot.Values;
 using TestStack.BDDfy;
 using Xunit;

@@ -18,6 +21,7 @@ namespace Ocelot.UnitTests.LoadBalancer
        private readonly LoadBalancerFactory _factory;
        private Response<ILoadBalancer> _result;
        private readonly Mock<IServiceDiscoveryProviderFactory> _serviceProviderFactory;
+        private readonly IEnumerable<ILoadBalancerCreator> _loadBalancerCreators;
        private readonly Mock<IServiceDiscoveryProvider> _serviceProvider;
        private ServiceProviderConfiguration _serviceProviderConfig;

@@ -25,7 +29,13 @@ namespace Ocelot.UnitTests.LoadBalancer
        {
            _serviceProviderFactory = new Mock<IServiceDiscoveryProviderFactory>();
            _serviceProvider = new Mock<IServiceDiscoveryProvider>();
-            _factory = new LoadBalancerFactory(_serviceProviderFactory.Object);
+            _loadBalancerCreators = new ILoadBalancerCreator[]
+            {
+                new FakeLoadBalancerCreator<FakeLoadBalancerOne>(),
+                new FakeLoadBalancerCreator<FakeLoadBalancerTwo>(),
+                new FakeLoadBalancerCreator<FakeNoLoadBalancer>(nameof(NoLoadBalancer)),
+            };
+            _factory = new LoadBalancerFactory(_serviceProviderFactory.Object, _loadBalancerCreators);
        }

        [Fact]
@@ -39,15 +49,15 @@ namespace Ocelot.UnitTests.LoadBalancer
                .And(x => GivenAServiceProviderConfig(new ServiceProviderConfigurationBuilder().Build()))
                .And(x => x.GivenTheServiceProviderFactoryReturns())
                .When(x => x.WhenIGetTheLoadBalancer())
-                .Then(x => x.ThenTheLoadBalancerIsReturned<NoLoadBalancer>())
+                .Then(x => x.ThenTheLoadBalancerIsReturned<FakeNoLoadBalancer>())
                .BDDfy();
        }

        [Fact]
-        public void should_return_round_robin_load_balancer()
+        public void should_return_matching_load_balancer()
        {
            var reRoute = new DownstreamReRouteBuilder()
-                .WithLoadBalancerOptions(new LoadBalancerOptions("RoundRobin", "", 0))
+                .WithLoadBalancerOptions(new LoadBalancerOptions("FakeLoadBalancerTwo", "", 0))
                .WithUpstreamHttpMethod(new List<string> { "Get" })
                .Build();

@@ -55,31 +65,15 @@ namespace Ocelot.UnitTests.LoadBalancer
                .And(x => GivenAServiceProviderConfig(new ServiceProviderConfigurationBuilder().Build()))
                .And(x => x.GivenTheServiceProviderFactoryReturns())
                .When(x => x.WhenIGetTheLoadBalancer())
-                .Then(x => x.ThenTheLoadBalancerIsReturned<RoundRobin>())
+                .Then(x => x.ThenTheLoadBalancerIsReturned<FakeLoadBalancerTwo>())
                .BDDfy();
        }
-
-        [Fact]
-        public void should_return_round_least_connection_balancer()
-        {
-            var reRoute = new DownstreamReRouteBuilder()
-                .WithLoadBalancerOptions(new LoadBalancerOptions("LeastConnection", "", 0))
-                .WithUpstreamHttpMethod(new List<string> { "Get" })
-                .Build();
-
-            this.Given(x => x.GivenAReRoute(reRoute))
-                .And(x => GivenAServiceProviderConfig(new ServiceProviderConfigurationBuilder().Build()))
-                .And(x => x.GivenTheServiceProviderFactoryReturns())
-                .When(x => x.WhenIGetTheLoadBalancer())
-                .Then(x => x.ThenTheLoadBalancerIsReturned<LeastConnection>())
-                .BDDfy();
-        }
-
+        
        [Fact]
        public void should_call_service_provider()
        {
            var reRoute = new DownstreamReRouteBuilder()
-                .WithLoadBalancerOptions(new LoadBalancerOptions("RoundRobin", "", 0))
+                .WithLoadBalancerOptions(new LoadBalancerOptions("FakeLoadBalancerOne", "", 0))
                .WithUpstreamHttpMethod(new List<string> { "Get" })
                .Build();

@@ -91,22 +85,6 @@ namespace Ocelot.UnitTests.LoadBalancer
                .BDDfy();
        }

-        [Fact]
-        public void should_return_sticky_session()
-        {
-            var reRoute = new DownstreamReRouteBuilder()
-                .WithLoadBalancerOptions(new LoadBalancerOptions("CookieStickySessions", "", 0))
-                .WithUpstreamHttpMethod(new List<string> { "Get" })
-                .Build();
-
-            this.Given(x => x.GivenAReRoute(reRoute))
-                .And(x => GivenAServiceProviderConfig(new ServiceProviderConfigurationBuilder().Build()))
-                .And(x => x.GivenTheServiceProviderFactoryReturns())
-                .When(x => x.WhenIGetTheLoadBalancer())
-                .Then(x => x.ThenTheLoadBalancerIsReturned<CookieStickySessions>())
-                .BDDfy();
-        }
-
        private void GivenAServiceProviderConfig(ServiceProviderConfiguration serviceProviderConfig)
        {
            _serviceProviderConfig = serviceProviderConfig;
@@ -139,5 +117,66 @@ namespace Ocelot.UnitTests.LoadBalancer
        {
            _result.Data.ShouldBeOfType<T>();
        }
+
+        private class FakeLoadBalancerCreator<T> : ILoadBalancerCreator
+            where T : ILoadBalancer, new()
+        {
+
+            public FakeLoadBalancerCreator()
+            {
+                Type = typeof(T).Name;
+            }
+
+            public FakeLoadBalancerCreator(string type)
+            {
+                Type = type;
+            }
+
+            public ILoadBalancer Create(DownstreamReRoute reRoute, IServiceDiscoveryProvider serviceProvider)
+            {
+                return new T();
+            }
+            
+            public string Type { get; }
+        }
+
+        private class FakeLoadBalancerOne : ILoadBalancer
+        {
+            public Task<Response<ServiceHostAndPort>> Lease(DownstreamContext context)
+            {
+                throw new System.NotImplementedException();
+            }
+
+            public void Release(ServiceHostAndPort hostAndPort)
+            {
+                throw new System.NotImplementedException();
+            }
+        }
+
+        private class FakeLoadBalancerTwo : ILoadBalancer
+        {
+            public Task<Response<ServiceHostAndPort>> Lease(DownstreamContext context)
+            {
+                throw new System.NotImplementedException();
+            }
+
+            public void Release(ServiceHostAndPort hostAndPort)
+            {
+                throw new System.NotImplementedException();
+            }
+        }
+
+        private class FakeNoLoadBalancer : ILoadBalancer
+        {
+            public Task<Response<ServiceHostAndPort>> Lease(DownstreamContext context)
+            {
+                throw new System.NotImplementedException();
+            }
+
+            public void Release(ServiceHostAndPort hostAndPort)
+            {
+                throw new System.NotImplementedException();
+            }
+        }
    }
 }
--- a/test/Ocelot.UnitTests/LoadBalancer/NoLoadBalancerCreatorTests.cs
+++ b/test/Ocelot.UnitTests/LoadBalancer/NoLoadBalancerCreatorTests.cs
@@ -0,0 +1,72 @@
+using Moq;
+using Ocelot.Configuration;
+using Ocelot.Configuration.Builder;
+using Ocelot.LoadBalancer.LoadBalancers;
+using Ocelot.ServiceDiscovery.Providers;
+using Shouldly;
+using TestStack.BDDfy;
+using Xunit;
+
+namespace Ocelot.UnitTests.LoadBalancer
+{
+    public class NoLoadBalancerCreatorTests
+    {
+        private readonly NoLoadBalancerCreator _creator;
+        private readonly Mock<IServiceDiscoveryProvider> _serviceProvider;
+        private DownstreamReRoute _reRoute;
+        private ILoadBalancer _loadBalancer;
+        private string _typeName;
+
+        public NoLoadBalancerCreatorTests()
+        {
+            _creator = new NoLoadBalancerCreator();
+            _serviceProvider = new Mock<IServiceDiscoveryProvider>();
+        }
+        
+        [Fact]
+        public void should_return_expected_name()
+        {
+            var reRoute = new DownstreamReRouteBuilder()
+                .Build();
+
+            this.Given(x => x.GivenAReRoute(reRoute))
+                .When(x => x.WhenIGetTheLoadBalancer())
+                .Then(x => x.ThenTheLoadBalancerIsReturned<NoLoadBalancer>())
+                .BDDfy();
+        }
+                
+        [Fact]
+        public void should_return_instance_of_expected_load_balancer_type()
+        {
+            this.When(x => x.WhenIGetTheLoadBalancerTypeName())
+                .Then(x => x.ThenTheLoadBalancerTypeIs("NoLoadBalancer"))
+                .BDDfy();
+        }
+
+        private void GivenAReRoute(DownstreamReRoute reRoute)
+        {
+            _reRoute = reRoute;
+        }
+
+        private void WhenIGetTheLoadBalancer()
+        {
+            _loadBalancer = _creator.Create(_reRoute, _serviceProvider.Object);
+        }
+        
+        private void WhenIGetTheLoadBalancerTypeName()
+        {
+            _typeName = _creator.Type;
+        }
+
+        private void ThenTheLoadBalancerIsReturned<T>()
+            where T : ILoadBalancer
+        {
+            _loadBalancer.ShouldBeOfType<T>();
+        }
+
+        private void ThenTheLoadBalancerTypeIs(string type)
+        {
+            _typeName.ShouldBe(type);
+        }
+    }
+}
--- a/test/Ocelot.UnitTests/LoadBalancer/RoundRobinCreatorTests.cs
+++ b/test/Ocelot.UnitTests/LoadBalancer/RoundRobinCreatorTests.cs
@@ -0,0 +1,72 @@
+using Moq;
+using Ocelot.Configuration;
+using Ocelot.Configuration.Builder;
+using Ocelot.LoadBalancer.LoadBalancers;
+using Ocelot.ServiceDiscovery.Providers;
+using Shouldly;
+using TestStack.BDDfy;
+using Xunit;
+
+namespace Ocelot.UnitTests.LoadBalancer
+{
+    public class RoundRobinCreatorTests
+    {
+        private readonly RoundRobinCreator _creator;
+        private readonly Mock<IServiceDiscoveryProvider> _serviceProvider;
+        private DownstreamReRoute _reRoute;
+        private ILoadBalancer _loadBalancer;
+        private string _typeName;
+
+        public RoundRobinCreatorTests()
+        {
+            _creator = new RoundRobinCreator();
+            _serviceProvider = new Mock<IServiceDiscoveryProvider>();
+        }
+        
+        [Fact]
+        public void should_return_expected_name()
+        {
+            var reRoute = new DownstreamReRouteBuilder()
+                .Build();
+
+            this.Given(x => x.GivenAReRoute(reRoute))
+                .When(x => x.WhenIGetTheLoadBalancer())
+                .Then(x => x.ThenTheLoadBalancerIsReturned<RoundRobin>())
+                .BDDfy();
+        }
+                
+        [Fact]
+        public void should_return_instance_of_expected_load_balancer_type()
+        {
+            this.When(x => x.WhenIGetTheLoadBalancerTypeName())
+                .Then(x => x.ThenTheLoadBalancerTypeIs("RoundRobin"))
+                .BDDfy();
+        }
+
+        private void GivenAReRoute(DownstreamReRoute reRoute)
+        {
+            _reRoute = reRoute;
+        }
+
+        private void WhenIGetTheLoadBalancer()
+        {
+            _loadBalancer = _creator.Create(_reRoute, _serviceProvider.Object);
+        }
+        
+        private void WhenIGetTheLoadBalancerTypeName()
+        {
+            _typeName = _creator.Type;
+        }
+
+        private void ThenTheLoadBalancerIsReturned<T>()
+            where T : ILoadBalancer
+        {
+            _loadBalancer.ShouldBeOfType<T>();
+        }
+
+        private void ThenTheLoadBalancerTypeIs(string type)
+        {
+            _typeName.ShouldBe(type);
+        }
+    }
+}