[PATCH] HTTP/2: add debug logging of control frames

[Piotr Sikora]

# HG changeset patch
# User Piotr Sikora <piotrsikora at google.com>
# Date 1490516711 25200
#      Sun Mar 26 01:25:11 2017 -0700
# Node ID 06d6418afe6e73604aea707ef9c5802f5bf27bf4
# Parent  22be63bf21edaa1b8ea916c7d8cd4e5fe4892061
HTTP/2: add debug logging of control frames.

Signed-off-by: Piotr Sikora <piotrsikora at google.com>

diff -r 22be63bf21ed -r 06d6418afe6e src/http/v2/ngx_http_v2.c
--- a/src/http/v2/ngx_http_v2.c
+++ b/src/http/v2/ngx_http_v2.c
@@ -1955,6 +1955,9 @@ ngx_http_v2_state_settings(ngx_http_v2_c
             return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_SIZE_ERROR);
         }
 
+        ngx_log_debug0(NGX_LOG_DEBUG_HTTP, h2c->connection->log, 0,
+                       "http2 SETTINGS frame ack:1");
+
         h2c->settings_ack = 1;
 
         return ngx_http_v2_state_complete(h2c, pos, end);
@@ -1968,6 +1971,10 @@ ngx_http_v2_state_settings(ngx_http_v2_c
         return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_SIZE_ERROR);
     }
 
+    ngx_log_debug1(NGX_LOG_DEBUG_HTTP, h2c->connection->log, 0,
+                   "http2 SETTINGS frame params:%uz",
+                   h2c->state.length / NGX_HTTP_V2_SETTINGS_PARAM_SIZE);
+
     ngx_http_v2_send_settings(h2c, 1);
 
     return ngx_http_v2_state_settings_params(h2c, pos, end);
@@ -2004,6 +2011,10 @@ ngx_http_v2_state_settings_params(ngx_ht
                                                   NGX_HTTP_V2_FLOW_CTRL_ERROR);
             }
 
+            ngx_log_debug1(NGX_LOG_DEBUG_HTTP, h2c->connection->log, 0,
+                           "http2 SETTINGS frame INITIAL_WINDOW_SIZE:%ui",
+                           value);
+
             if (ngx_http_v2_adjust_windows(h2c, value - h2c->init_window)
                 != NGX_OK)
             {
@@ -2026,6 +2037,10 @@ ngx_http_v2_state_settings_params(ngx_ht
                                                     NGX_HTTP_V2_PROTOCOL_ERROR);
             }
 
+            ngx_log_debug1(NGX_LOG_DEBUG_HTTP, h2c->connection->log, 0,
+                           "http2 SETTINGS frame MAX_FRAME_SIZE:%ui",
+                           value);
+
             h2c->frame_size = value;
             break;
 
@@ -2070,12 +2085,16 @@ ngx_http_v2_state_ping(ngx_http_v2_conne
     }
 
     ngx_log_debug1(NGX_LOG_DEBUG_HTTP, h2c->connection->log, 0,
-                   "http2 PING frame, flags: %ud", h2c->state.flags);
+                   "http2 PING frame ack:%ud",
+                   h2c->state.flags & NGX_HTTP_V2_ACK_FLAG ? 1 : 0);
 
     if (h2c->state.flags & NGX_HTTP_V2_ACK_FLAG) {
         return ngx_http_v2_state_skip(h2c, pos, end);
     }
 
+    ngx_log_debug0(NGX_LOG_DEBUG_HTTP, h2c->connection->log, 0,
+                   "http2 send PING frame ack:1");
+
     frame = ngx_http_v2_get_frame(h2c, NGX_HTTP_V2_PING_SIZE,
                                   NGX_HTTP_V2_PING_FRAME,
                                   NGX_HTTP_V2_ACK_FLAG, 0);
@@ -2449,8 +2468,18 @@ ngx_http_v2_send_settings(ngx_http_v2_co
     ngx_http_v2_srv_conf_t   *h2scf;
     ngx_http_v2_out_frame_t  *frame;
 
-    ngx_log_debug1(NGX_LOG_DEBUG_HTTP, h2c->connection->log, 0,
-                   "http2 send SETTINGS frame ack:%ui", ack);
+    if (ack) {
+        ngx_log_debug0(NGX_LOG_DEBUG_HTTP, h2c->connection->log, 0,
+                       "http2 send SETTINGS frame ack:1");
+
+        len = 0;
+
+    } else {
+        ngx_log_debug0(NGX_LOG_DEBUG_HTTP, h2c->connection->log, 0,
+                       "http2 send SETTINGS frame params:3");
+
+        len = NGX_HTTP_V2_SETTINGS_PARAM_SIZE * 3;
+    }
 
     frame = ngx_palloc(h2c->pool, sizeof(ngx_http_v2_out_frame_t));
     if (frame == NULL) {
@@ -2462,8 +2491,6 @@ ngx_http_v2_send_settings(ngx_http_v2_co
         return NGX_ERROR;
     }
 
-    len = ack ? 0 : (sizeof(uint16_t) + sizeof(uint32_t)) * 3;
-
     buf = ngx_create_temp_buf(h2c->pool, NGX_HTTP_V2_FRAME_HEADER_SIZE + len);
     if (buf == NULL) {
         return NGX_ERROR;
@@ -2494,15 +2521,27 @@ ngx_http_v2_send_settings(ngx_http_v2_co
         h2scf = ngx_http_get_module_srv_conf(h2c->http_connection->conf_ctx,
                                              ngx_http_v2_module);
 
+        ngx_log_debug1(NGX_LOG_DEBUG_HTTP, h2c->connection->log, 0,
+                       "http2 send SETTINGS frame MAX_CONCURRENT_STREAMS:%ui",
+                       h2scf->concurrent_streams);
+
         buf->last = ngx_http_v2_write_uint16(buf->last,
                                              NGX_HTTP_V2_MAX_STREAMS_SETTING);
         buf->last = ngx_http_v2_write_uint32(buf->last,
                                              h2scf->concurrent_streams);
 
+        ngx_log_debug1(NGX_LOG_DEBUG_HTTP, h2c->connection->log, 0,
+                       "http2 send SETTINGS frame INITIAL_WINDOW_SIZE:%uz",
+                       h2scf->preread_size);
+
         buf->last = ngx_http_v2_write_uint16(buf->last,
                                          NGX_HTTP_V2_INIT_WINDOW_SIZE_SETTING);
         buf->last = ngx_http_v2_write_uint32(buf->last, h2scf->preread_size);
 
+        ngx_log_debug1(NGX_LOG_DEBUG_HTTP, h2c->connection->log, 0,
+                       "http2 send SETTINGS frame MAX_FRAME_SIZE:%ud",
+                       NGX_HTTP_V2_MAX_FRAME_SIZE);
+
         buf->last = ngx_http_v2_write_uint16(buf->last,
                                            NGX_HTTP_V2_MAX_FRAME_SIZE_SETTING);
         buf->last = ngx_http_v2_write_uint32(buf->last,