#473 dont remove query string param (#481)

src/Ocelot/DownstreamUrlCreator/Middleware/DownstreamUrlCreatorMiddleware.cs

@@ -52,7 +52,15 @@ namespace Ocelot.DownstreamUrlCreator.Middleware
                 if(ContainsQueryString(dsPath))
                 {
                     context.DownstreamRequest.AbsolutePath = GetPath(dsPath);
-                    context.DownstreamRequest.Query = GetQueryString(dsPath);
+
+                    if (string.IsNullOrEmpty(context.DownstreamRequest.Query))
+                    {
+                        context.DownstreamRequest.Query = GetQueryString(dsPath);
+                    }
+                    else
+                    {
+                        context.DownstreamRequest.Query += GetQueryString(dsPath).Replace('?', '&');
+                    }
                 }
                 else
                 {

test/Ocelot.UnitTests/DownstreamUrlCreator/DownstreamUrlCreatorMiddlewareTests.cs

@@ -289,6 +289,39 @@
                 .BDDfy();
         }
 
+        [Fact]
+        public void issue_473_should_not_remove_additional_query_string()
+        {
+            var downstreamReRoute = new DownstreamReRouteBuilder()
+                .WithDownstreamPathTemplate("/Authorized/{action}?server={server}")
+                .WithUpstreamHttpMethod(new List<string> { "Post", "Get" })
+                .WithDownstreamScheme("http")
+                .WithUpstreamPathTemplate("/uc/Authorized/{server}/{action}")
+                .Build();
+
+            var config = new ServiceProviderConfigurationBuilder()
+                .Build();
+
+            this.Given(x => x.GivenTheDownStreamRouteIs(
+                    new DownstreamRoute(
+                        new List<PlaceholderNameAndValue>
+                        {
+                            new PlaceholderNameAndValue("{action}", "1"),
+                            new PlaceholderNameAndValue("{server}", "2")
+                        },
+                        new ReRouteBuilder()
+                            .WithDownstreamReRoute(downstreamReRoute)
+                            .WithUpstreamHttpMethod(new List<string> { "Post", "Get" })
+                            .Build())))
+                .And(x => x.GivenTheDownstreamRequestUriIs("http://localhost:5000/uc/Authorized/2/1/refresh?refreshToken=2288356cfb1338fdc5ff4ca558ec785118dfe1ff2864340937da8226863ff66d"))
+                .And(x => GivenTheServiceProviderConfigIs(config))
+                .And(x => x.GivenTheUrlReplacerWillReturn("/Authorized/1?server=2"))
+                .When(x => x.WhenICallTheMiddleware())
+                .Then(x => x.ThenTheDownstreamRequestUriIs("http://localhost:5000/Authorized/1?refreshToken=2288356cfb1338fdc5ff4ca558ec785118dfe1ff2864340937da8226863ff66d&server=2"))
+                .And(x => ThenTheQueryStringIs("?refreshToken=2288356cfb1338fdc5ff4ca558ec785118dfe1ff2864340937da8226863ff66d&server=2"))
+                .BDDfy();
+        }
+
         private void GivenTheServiceProviderConfigIs(ServiceProviderConfiguration config)
         {
             var configuration = new InternalConfiguration(null, null, config, null, null, null, null, null);