close COUCHDB-795 add X-HTTP-METHOD-OVERRIDE support. Thanks Brian Jenkins

git-svn-id: https://svn.apache.org/repos/asf/couchdb/trunk@957610 13f79535-47bb-0310-9956-ffa450edef68

1 files changed, 19 insertions, 2 deletions

diff --git a/src/couchdb/couch_httpd.erl b/src/couchdb/couch_httpd.erl
index 331546eb..cb71203a 100644
--- a/src/couchdb/couch_httpd.erl
+++ b/src/couchdb/couch_httpd.erl
@@ -218,9 +218,26 @@ handle_request_int(MochiReq, DefaultFun,
         Meth -> couch_util:to_existing_atom(Meth)
     end,
     increment_method_stats(Method1),
+
+    % allow broken HTTP clients to fake a full method vocabulary with an X-HTTP-METHOD-OVERRIDE header
+    MethodOverride = MochiReq:get_primary_header_value("X-HTTP-Method-Override"),
+    Method2 = case lists:member(MethodOverride, ["GET", "HEAD", "POST", "PUT", "DELETE", "TRACE", "CONNECT", "COPY"]) of
+    true -> 
+        ?LOG_INFO("MethodOverride: ~s (real method was ~s)", [MethodOverride, Method1]),
+        case Method1 of
+        'POST' -> list_to_atom(MethodOverride);
+        _ -> 
+            % Ignore X-HTTP-Method-Override when the original verb isn't POST.
+            % I'd like to send a 406 error to the client, but that'd require a nasty refactor.
+            % throw({not_acceptable, <<"X-HTTP-Method-Override may only be used with POST requests.">>})
+            Method1
+        end;
+    _ -> Method1
+    end,
+
     % alias HEAD to GET as mochiweb takes care of stripping the body
-    Method = case Method1 of
-        'HEAD' -> 'GET';
+    Method = case Method2 of
+            'HEAD' -> 'GET';
         Other -> Other
     end,