From 45b0d0d0de331b347a73e62b90dc73b2b38d6db8 Mon Sep 17 00:00:00 2001
From: Justin Kotalik <jukotali@microsoft.com>
Date: Mon, 3 Jun 2019 22:31:38 -0700
Subject: [PATCH] Save condition backcollection between runs (#10776)

---
 .../ApacheModRewrite/ApacheModRewriteRule.cs  |  6 +++--
 .../ModRewriteMiddlewareTest.cs               | 22 ++++++++++++++++++-
 2 files changed, 25 insertions(+), 3 deletions(-)

diff --git a/src/Middleware/Rewrite/src/Internal/ApacheModRewrite/ApacheModRewriteRule.cs b/src/Middleware/Rewrite/src/Internal/ApacheModRewrite/ApacheModRewriteRule.cs
index 32be7fe80d..04abcb1221 100644
--- a/src/Middleware/Rewrite/src/Internal/ApacheModRewrite/ApacheModRewriteRule.cs
+++ b/src/Middleware/Rewrite/src/Internal/ApacheModRewrite/ApacheModRewriteRule.cs
@@ -1,4 +1,4 @@
-// Copyright (c) .NET Foundation. All rights reserved.
+// Copyright (c) .NET Foundation. All rights reserved.
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
 using System.Collections.Generic;
@@ -39,6 +39,8 @@ namespace Microsoft.AspNetCore.Rewrite.Internal.ApacheModRewrite
                     context.Logger?.ModRewriteNotMatchedRule();
                     return;
                 }
+
+                condBackReferences = condResult.BackReferences;
             }
 
             // At this point, we know our rule passed, first apply pre conditions,
@@ -51,4 +53,4 @@ namespace Microsoft.AspNetCore.Rewrite.Internal.ApacheModRewrite
             }
         }
     }
-}
\ No newline at end of file
+}
diff --git a/src/Middleware/Rewrite/test/ApacheModRewrite/ModRewriteMiddlewareTest.cs b/src/Middleware/Rewrite/test/ApacheModRewrite/ModRewriteMiddlewareTest.cs
index f22f340f18..67deba236d 100644
--- a/src/Middleware/Rewrite/test/ApacheModRewrite/ModRewriteMiddlewareTest.cs
+++ b/src/Middleware/Rewrite/test/ApacheModRewrite/ModRewriteMiddlewareTest.cs
@@ -1,4 +1,4 @@
-// Copyright (c) .NET Foundation. All rights reserved.
+// Copyright (c) .NET Foundation. All rights reserved.
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
 using System;
@@ -308,5 +308,25 @@ namespace Microsoft.AspNetCore.Rewrite.Tests.ModRewrite
 
             Assert.Equal("/foo", response.Headers.Location.OriginalString);
         }
+
+        [Fact]
+        public async Task CapturedVariablesInConditionsArePreservedToRewriteRule()
+        {
+            var options = new RewriteOptions().AddApacheModRewrite(new StringReader(@"RewriteCond %{REQUEST_URI} /home
+RewriteCond %{QUERY_STRING} report_id=(.+)
+RewriteRule (.*) http://localhost:80/home/report/%1 [R=301,L,QSD]"));
+            var builder = new WebHostBuilder().Configure(app =>
+               {
+                   app.UseRewriter(options);
+                   app.Run(context => context.Response.WriteAsync(
+                           context.Request.Path +
+                           context.Request.QueryString));
+               });
+
+            var server = new TestServer(builder) { BaseAddress = new Uri("http://localhost:5000/foo") };
+            var response = await server.CreateClient().GetAsync("/home?report_id=123");
+
+            Assert.Equal("http://localhost:80/home/report/123", response.Headers.Location.OriginalString);
+        }
     }
 }