commit f0ee4eb986fbd3a5368587ad39c4f898c3ec98c9
author Roman Arutyunyan <arut@nginx.com> Wed Nov 11 15:47:30 2015 +0300
committer Roman Arutyunyan <arut@nginx.com> Wed Nov 11 15:47:30 2015 +0300
tree e21a83691a7fe266008f413d14966cec9b89604c
parent ea7af3edef88be48759bbcc4d1a9264e29b044d7

Upstream: proxy_cache_convert_head directive.

The directive toggles conversion of HEAD to GET for cacheable proxy requests.
When disabled, $request_method must be added to cache key for consistency.
By default, HEAD is converted to GET as before.

src/http/modules/ngx_http_proxy_module.c

diff --git a/src/http/modules/ngx_http_proxy_module.c b/src/http/modules/ngx_http_proxy_module.c
index 514c23b..1933509 100644
--- a/src/http/modules/ngx_http_proxy_module.c
+++ b/src/http/modules/ngx_http_proxy_module.c
@@ -533,6 +533,13 @@
       offsetof(ngx_http_proxy_loc_conf_t, upstream.cache_revalidate),
       NULL },
 
+    { ngx_string("proxy_cache_convert_head"),
+      NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_FLAG,
+      ngx_conf_set_flag_slot,
+      NGX_HTTP_LOC_CONF_OFFSET,
+      offsetof(ngx_http_proxy_loc_conf_t, upstream.cache_convert_head),
+      NULL },
+
 #endif
 
     { ngx_string("proxy_temp_path"),
@@ -2845,6 +2852,7 @@
     conf->upstream.cache_lock_timeout = NGX_CONF_UNSET_MSEC;
     conf->upstream.cache_lock_age = NGX_CONF_UNSET_MSEC;
     conf->upstream.cache_revalidate = NGX_CONF_UNSET;
+    conf->upstream.cache_convert_head = NGX_CONF_UNSET;
 #endif
 
     conf->upstream.hide_headers = NGX_CONF_UNSET_PTR;
@@ -3143,6 +3151,9 @@
     ngx_conf_merge_value(conf->upstream.cache_revalidate,
                               prev->upstream.cache_revalidate, 0);
 
+    ngx_conf_merge_value(conf->upstream.cache_convert_head,
+                              prev->upstream.cache_convert_head, 1);
+
 #endif
 
     ngx_conf_merge_str_value(conf->method, prev->method, "");

src/http/ngx_http_upstream.c

diff --git a/src/http/ngx_http_upstream.c b/src/http/ngx_http_upstream.c
index 1530596..74fffd5 100644
--- a/src/http/ngx_http_upstream.c
+++ b/src/http/ngx_http_upstream.c
@@ -764,7 +764,7 @@
             return rc;
         }
 
-        if (r->method & NGX_HTTP_HEAD) {
+        if ((r->method & NGX_HTTP_HEAD) && u->conf->cache_convert_head) {
             u->method = ngx_http_core_get_method;
         }
 

src/http/ngx_http_upstream.h

diff --git a/src/http/ngx_http_upstream.h b/src/http/ngx_http_upstream.h
index 64157e6..8404265 100644
--- a/src/http/ngx_http_upstream.h
+++ b/src/http/ngx_http_upstream.h
@@ -193,6 +193,7 @@
     ngx_msec_t                       cache_lock_age;
 
     ngx_flag_t                       cache_revalidate;
+    ngx_flag_t                       cache_convert_head;
 
     ngx_array_t                     *cache_valid;
     ngx_array_t                     *cache_bypass;