# HG changeset patch
# User Maxim Dounin <mdounin@mdounin.ru>
# Date 1341845622 0
# Node ID 613750237b365bc5c427c3a51e4f40f69ed1dad0
# Parent  192f54280a7aa85168b3d3f1c000951bb9305309
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.

diff --git a/src/http/ngx_http_core_module.c b/src/http/ngx_http_core_module.c
--- 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_comm
       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
     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 
     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);
diff --git a/src/http/ngx_http_core_module.h b/src/http/ngx_http_core_module.h
--- a/src/http/ngx_http_core_module.h
+++ b/src/http/ngx_http_core_module.h
@@ -392,6 +392,7 @@ struct ngx_http_core_loc_conf_s {
     ngx_flag_t    recursive_error_pages;   /* recursive_error_pages */
     ngx_flag_t    server_tokens;           /* server_tokens */
     ngx_flag_t    chunked_transfer_encoding; /* chunked_transfer_encoding */
+    ngx_flag_t    etag;                    /* etag */
 
 #if (NGX_HTTP_GZIP)
     ngx_flag_t    gzip_vary;               /* gzip_vary */