Entity tags: the "etag" directive.

It allows to disable generation of nginx's own entity tags, while
still handling ETags in cache properly.  This may be useful e.g.
if one want to serve static files from servers with different ETag
generation algorithms.

1 files changed, 17 insertions, 1 deletions

diff --git a/src/http/ngx_http_core_module.c b/src/http/ngx_http_core_module.c
index ebc9f7413..a8177aef7 100644
--- a/src/http/ngx_http_core_module.c
+++ b/src/http/ngx_http_core_module.c
@@ -650,6 +650,13 @@ static ngx_command_t  ngx_http_core_commands[] = {
       offsetof(ngx_http_core_loc_conf_t, chunked_transfer_encoding),
       NULL },
 
+    { ngx_string("etag"),
+      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_core_loc_conf_t, etag),
+      NULL },
+
     { ngx_string("error_page"),
       NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_HTTP_LIF_CONF
                         |NGX_CONF_2MORE,
@@ -1811,7 +1818,14 @@ ngx_http_set_exten(ngx_http_request_t *r)
 ngx_int_t
 ngx_http_set_etag(ngx_http_request_t *r)
 {
-    ngx_table_elt_t  *etag;
+    ngx_table_elt_t           *etag;
+    ngx_http_core_loc_conf_t  *clcf;
+    
+    clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module);
+ 
+    if (!clcf->etag) {
+        return NGX_OK;
+    }
 
     etag = ngx_list_push(&r->headers_out.headers);
     if (etag == NULL) {
@@ -3539,6 +3553,7 @@ ngx_http_core_create_loc_conf(ngx_conf_t *cf)
     clcf->recursive_error_pages = NGX_CONF_UNSET;
     clcf->server_tokens = NGX_CONF_UNSET;
     clcf->chunked_transfer_encoding = NGX_CONF_UNSET;
+    clcf->etag = NGX_CONF_UNSET;
     clcf->types_hash_max_size = NGX_CONF_UNSET_UINT;
     clcf->types_hash_bucket_size = NGX_CONF_UNSET_UINT;
 
@@ -3800,6 +3815,7 @@ ngx_http_core_merge_loc_conf(ngx_conf_t *cf, void *parent, void *child)
     ngx_conf_merge_value(conf->server_tokens, prev->server_tokens, 1);
     ngx_conf_merge_value(conf->chunked_transfer_encoding,
                               prev->chunked_transfer_encoding, 1);
+    ngx_conf_merge_value(conf->etag, prev->etag, 1);
 
     ngx_conf_merge_ptr_value(conf->open_file_cache,
                               prev->open_file_cache, NULL);