From: Baptiste Assmann <bedis9@gmail.com>
Date: Wed, 7 Aug 2019 10:24:36 +0000 (+0200)
Subject: MINOR: cache: allow caching of OPTIONS request
X-Git-Tag: v2.1-dev2~223
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=1263540fe824c74bc3c668fec3476b880d65b27c;p=thirdparty%2Fhaproxy.git

MINOR: cache: allow caching of OPTIONS request

Allow HAProxy to cache responses to OPTIONS HTTP requests.
This is useful in the use case of "Cross-Origin Resource Sharing" (cors)
to cache CORS responses from API servers.

Since HAProxy does not support Vary header for now, this would be only
useful for "access-control-allow-origin: *" use case.
---

diff --git a/src/cache.c b/src/cache.c
index 5b4062384a..001532651d 100644
--- a/src/cache.c
+++ b/src/cache.c
@@ -560,8 +560,8 @@ enum act_return http_action_store_cache(struct act_rule *rule, struct proxy *px,
 	if (!(txn->req.flags & HTTP_MSGF_VER_11))
 		goto out;
 
-	/* cache only GET method */
-	if (txn->meth != HTTP_METH_GET)
+	/* cache only GET or OPTIONS method */
+	if (txn->meth != HTTP_METH_GET && txn->meth != HTTP_METH_OPTIONS)
 		goto out;
 
 	/* cache key was not computed */
@@ -1058,6 +1058,9 @@ int sha1_hosturi(struct stream *s)
 	ctx.blk = NULL;
 
 	switch (txn->meth) {
+	case HTTP_METH_OPTIONS:
+		chunk_memcat(trash, "OPTIONS", 7);
+		break;
 	case HTTP_METH_HEAD:
 	case HTTP_METH_GET:
 		chunk_memcat(trash, "GET", 3);
@@ -1093,10 +1096,10 @@ enum act_return http_action_req_cache_use(struct act_rule *rule, struct proxy *p
 	struct cache_flt_conf *cconf = rule->arg.act.p[0];
 	struct cache *cache = cconf->c.cache;
 
-	/* Ignore cache for HTTP/1.0 requests and for requests other than GET
-	 * and HEAD */
+	/* Ignore cache for HTTP/1.0 requests and for requests other than GET,
+	 * HEAD and OPTIONS */
 	if (!(txn->req.flags & HTTP_MSGF_VER_11) ||
-	    (txn->meth != HTTP_METH_GET && txn->meth != HTTP_METH_HEAD))
+	    (txn->meth != HTTP_METH_GET && txn->meth != HTTP_METH_HEAD && txn->meth != HTTP_METH_OPTIONS))
 		txn->flags |= TX_CACHE_IGNORE;
 
 	http_check_request_for_cacheability(s, &s->req);