Upstream: different header lists for cached and uncached requests.
The upstream modules remove and alter a number of client headers
before sending the request to upstream. This set of headers is
smaller or even empty when cache is disabled.
It's still possible that a request in a cache-enabled location is
uncached, for example, if cache entry counter is below min_uses.
In this case it's better to alter a smaller set of headers and
pass more client headers to backend unchanged. One of the benefits
is enabling server-side byte ranges in such requests.
diff --git a/src/http/modules/ngx_http_proxy_module.c b/src/http/modules/ngx_http_proxy_module.c
index 987e03e..91108a8 100644
--- a/src/http/modules/ngx_http_proxy_module.c
+++ b/src/http/modules/ngx_http_proxy_module.c
@@ -55,6 +55,9 @@
ngx_array_t *body_set;
ngx_http_proxy_headers_t headers;
+#if (NGX_HTTP_CACHE)
+ ngx_http_proxy_headers_t headers_cache;
+#endif
ngx_array_t *headers_source;
ngx_array_t *proxy_lengths;
@@ -153,7 +156,8 @@
static char *ngx_http_proxy_merge_loc_conf(ngx_conf_t *cf,
void *parent, void *child);
static ngx_int_t ngx_http_proxy_init_headers(ngx_conf_t *cf,
- ngx_http_proxy_loc_conf_t *conf, ngx_http_proxy_headers_t *headers);
+ ngx_http_proxy_loc_conf_t *conf, ngx_http_proxy_headers_t *headers,
+ ngx_keyval_t *default_headers);
static char *ngx_http_proxy_pass(ngx_conf_t *cf, ngx_command_t *cmd,
void *conf);
@@ -1095,7 +1099,11 @@
plcf = ngx_http_get_module_loc_conf(r, ngx_http_proxy_module);
+#if (NGX_HTTP_CACHE)
+ headers = u->cacheable ? &plcf->headers_cache : &plcf->headers;
+#else
headers = &plcf->headers;
+#endif
if (u->method.len) {
/* HEAD was changed to GET to cache response */
@@ -2515,6 +2523,9 @@
* conf->headers.lengths = NULL;
* conf->headers.values = NULL;
* conf->headers.hash = { NULL, 0 };
+ * conf->headers_cache.lengths = NULL;
+ * conf->headers_cache.values = NULL;
+ * conf->headers_cache.hash = { NULL, 0 };
* conf->body_set_len = NULL;
* conf->body_set = NULL;
* conf->body_source = { 0, NULL };
@@ -2606,6 +2617,7 @@
u_char *p;
size_t size;
+ ngx_int_t rc;
ngx_hash_init_t hash;
ngx_http_core_loc_conf_t *clcf;
ngx_http_proxy_rewrite_t *pr;
@@ -3028,26 +3040,37 @@
if (conf->headers_source == NULL) {
conf->headers = prev->headers;
+#if (NGX_HTTP_CACHE)
+ conf->headers_cache = prev->headers_cache;
+#endif
conf->headers_source = prev->headers_source;
}
-#if (NGX_HTTP_CACHE)
- if ((conf->upstream.cache == NULL) != (prev->upstream.cache == NULL)) {
- conf->headers.hash.buckets = NULL;
- }
-#endif
-
- if (ngx_http_proxy_init_headers(cf, conf, &conf->headers) != NGX_OK) {
+ rc = ngx_http_proxy_init_headers(cf, conf, &conf->headers,
+ ngx_http_proxy_headers);
+ if (rc != NGX_OK) {
return NGX_CONF_ERROR;
}
+#if (NGX_HTTP_CACHE)
+
+ if (conf->upstream.cache) {
+ rc = ngx_http_proxy_init_headers(cf, conf, &conf->headers_cache,
+ ngx_http_proxy_cache_headers);
+ if (rc != NGX_OK) {
+ return NGX_CONF_ERROR;
+ }
+ }
+
+#endif
+
return NGX_CONF_OK;
}
static ngx_int_t
ngx_http_proxy_init_headers(ngx_conf_t *cf, ngx_http_proxy_loc_conf_t *conf,
- ngx_http_proxy_headers_t *headers)
+ ngx_http_proxy_headers_t *headers, ngx_keyval_t *default_headers)
{
u_char *p;
size_t size;
@@ -3094,17 +3117,6 @@
return NGX_ERROR;
}
-
-#if (NGX_HTTP_CACHE)
-
- h = conf->upstream.cache ? ngx_http_proxy_cache_headers:
- ngx_http_proxy_headers;
-#else
-
- h = ngx_http_proxy_headers;
-
-#endif
-
src = conf->headers_source->elts;
for (i = 0; i < conf->headers_source->nelts; i++) {
@@ -3116,6 +3128,8 @@
*s = src[i];
}
+ h = default_headers;
+
while (h->key.len) {
src = headers_merged.elts;
