When running with gzip support enabled, ignore "accept-encoding" in

vary-matching.  Varnish will adapt whatever we find to the clients
abilities as necessary.

bin/varnishd/cache_vary.c

@@ -144,6 +144,24 @@ VRY_Match(const struct sess *sp, const unsigned char *vary)
 
 	while (*vary) {
 
+		if (params->http_gzip_support &&
+		    !strcasecmp(H_Accept_Encoding, (const char*)vary)) {
+			/*
+			 * If we do gzip processing, we do not vary on
+			 * Accept-Encoding, because we want everybody to
+			 * get the gzip'ed object, and varnish will gunzip
+			 * as necessary.  We implement the skip at check
+			 * time, rather than create time, so that object
+			 * in persistent storage can be used with either
+			 *  setting of http_gzip_support.
+			 */
+			vary += *vary + 2;
+			l = vary[0] * 256 + vary[1];
+			vary += 2;
+			if (l != 0xffff)
+				vary += l;
+			continue;
+		}
 		/* Look for header */
 		i = http_GetHdr(sp->http, (const char*)vary, &h);
 		vary += *vary + 2;

bin/varnishtest/tests/e00025.vtc

+# $Id$
+
+test "Test that esi+gzip correctly bypasses Vary: accept-encoding"
+
+server s1 {
+	rxreq 
+	expect req.http.accept-encoding == gzip
+	txresp -hdr "Vary: Accept-encoding" -gzipbody {FOO}
+} -start
+
+varnish v1 -vcl+backend { } -start
+
+client c1 {
+	txreq -hdr "Accept-encoding: gzip"
+	rxresp
+	expect resp.http.content-encoding == gzip
+	expect resp.status == 200
+	gunzip
+	expect resp.bodylen == 3
+
+	txreq 
+	rxresp
+	expect resp.http.content-encoding == resp.http.content-encoding
+	expect resp.status == 200
+	expect resp.bodylen == 3
+} -run