Upstream: revised upstream response time variables.

Variables now do not depend on presence of the HTTP status code in response.
If the corresponding event occurred, variables contain time between request
creation and the event, and "-" otherwise.

Previously, intermediate value of the $upstream_response_time variable held
unix timestamp.

2 files changed, 19 insertions, 15 deletions

diff --git a/src/http/ngx_http_upstream.c b/src/http/ngx_http_upstream.c
index 22c2afd67..3fa86c8f9 100644
--- a/src/http/ngx_http_upstream.c
+++ b/src/http/ngx_http_upstream.c
@@ -1505,8 +1505,8 @@ ngx_http_upstream_connect(ngx_http_request_t *r, ngx_http_upstream_t *u)
 
     r->connection->log->action = "connecting to upstream";
 
-    if (u->state && u->state->response_time) {
-        u->state->response_time = ngx_current_msec - u->state->response_time;
+    if (u->state && u->state->response_time == (ngx_msec_t) -1) {
+        u->state->response_time = ngx_current_msec - u->start_time;
     }
 
     u->state = ngx_array_push(r->upstream_states);
@@ -1518,7 +1518,9 @@ ngx_http_upstream_connect(ngx_http_request_t *r, ngx_http_upstream_t *u)
 
     ngx_memzero(u->state, sizeof(ngx_http_upstream_state_t));
 
-    u->state->response_time = ngx_current_msec;
+    u->start_time = ngx_current_msec;
+
+    u->state->response_time = (ngx_msec_t) -1;
     u->state->connect_time = (ngx_msec_t) -1;
     u->state->header_time = (ngx_msec_t) -1;
 
@@ -2002,7 +2004,7 @@ ngx_http_upstream_send_request(ngx_http_request_t *r, ngx_http_upstream_t *u,
                    "http upstream send request");
 
     if (u->state->connect_time == (ngx_msec_t) -1) {
-        u->state->connect_time = ngx_current_msec - u->state->response_time;
+        u->state->connect_time = ngx_current_msec - u->start_time;
     }
 
     if (!u->request_sent && ngx_http_upstream_test_connect(c) != NGX_OK) {
@@ -2413,7 +2415,7 @@ ngx_http_upstream_process_header(ngx_http_request_t *r, ngx_http_upstream_t *u)
 
     /* rc == NGX_OK */
 
-    u->state->header_time = ngx_current_msec - u->state->response_time;
+    u->state->header_time = ngx_current_msec - u->start_time;
 
     if (u->headers_in.status_n >= NGX_HTTP_SPECIAL_RESPONSE) {
 
@@ -4309,8 +4311,8 @@ ngx_http_upstream_finalize_request(ngx_http_request_t *r,
         u->resolved->ctx = NULL;
     }
 
-    if (u->state && u->state->response_time) {
-        u->state->response_time = ngx_current_msec - u->state->response_time;
+    if (u->state && u->state->response_time == (ngx_msec_t) -1) {
+        u->state->response_time = ngx_current_msec - u->start_time;
 
         if (u->pipe && u->pipe->read_length) {
             u->state->bytes_received += u->pipe->read_length
@@ -5419,18 +5421,18 @@ ngx_http_upstream_response_time_variable(ngx_http_request_t *r,
     state = r->upstream_states->elts;
 
     for ( ;; ) {
-        if (state[i].status) {
 
-            if (data == 1 && state[i].header_time != (ngx_msec_t) -1) {
-                ms = state[i].header_time;
+        if (data == 1) {
+            ms = state[i].header_time;
 
-            } else if (data == 2 && state[i].connect_time != (ngx_msec_t) -1) {
-                ms = state[i].connect_time;
+        } else if (data == 2) {
+            ms = state[i].connect_time;
 
-            } else {
-                ms = state[i].response_time;
-            }
+        } else {
+            ms = state[i].response_time;
+        }
 
+        if (ms != -1) {
             ms = ngx_max(ms, 0);
             p = ngx_sprintf(p, "%T.%03M", (time_t) ms / 1000, ms % 1000);
 
diff --git a/src/http/ngx_http_upstream.h b/src/http/ngx_http_upstream.h
index f875b7485..af84e24be 100644
--- a/src/http/ngx_http_upstream.h
+++ b/src/http/ngx_http_upstream.h
@@ -365,6 +365,8 @@ struct ngx_http_upstream_s {
     ngx_int_t                      (*rewrite_cookie)(ngx_http_request_t *r,
                                          ngx_table_elt_t *h);
 
+    ngx_msec_t                       start_time;
+
     ngx_http_upstream_state_t       *state;
 
     ngx_str_t                        method;