From 246a024dce1db84060a0efe518addc8ef3dc9097 Mon Sep 17 00:00:00 2001
From: "David L. L. Thomas" <davidleothomas@gmail.com>
Date: Fri, 23 Nov 2012 13:44:31 -0800
Subject: [PATCH] Allowing cache on 301 redirects

---
 yesod-core/Yesod/Handler.hs | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/yesod-core/Yesod/Handler.hs b/yesod-core/Yesod/Handler.hs
index 226c10a4..651ac200 100644
--- a/yesod-core/Yesod/Handler.hs
+++ b/yesod-core/Yesod/Handler.hs
@@ -522,11 +522,12 @@ runHandler handler mrender sroute tomr master sub upload log' =
                 Right c' -> return $ YARPlain status (appEndo headers []) ct c' finalSession
         HCError e -> handleError e
         HCRedirect status loc -> do
-            let hs =
+            let disable_caching =
                     [ Header "Cache-Control" "no-cache, must-revalidate"
                     , Header "Expires" "Thu, 01 Jan 1970 05:05:05 GMT"
-                    , Header "Location" (encodeUtf8 loc)
-                    ] ++ appEndo headers []
+                    ]
+                hs = (if status == H.movedPermanently301 then disable_caching else [])
+                      ++ Header "Location" (encodeUtf8 loc) : appEndo headers []
             return $ YARPlain
                 status hs typePlain emptyContent
                 finalSession