perf(*): perhaps a slightly faster VIA headers

Signed-off-by: Aapo Talvensaari <aapo.talvensaari@gmail.com>
Kong · Sep 6, 2024 · 3f5526f · 3f5526f
1 parent b861d1f
commit 3f5526f
Showing 1 changed file with 13 additions and 26 deletions.
diff --git a/kong/runloop/handler.lua b/kong/runloop/handler.lua
@@ -72,7 +72,7 @@ local ROUTER_CACHE = lrucache.new(ROUTER_CACHE_SIZE)
 local ROUTER_CACHE_NEG = lrucache.new(ROUTER_CACHE_SIZE)
 
 
-local DEFAULT_PROXY_HTTP_VERSION = "1.1"
+local DEFAULT_PROXY_HTTP_VERSION = 1.1
 
 
 local NOOP = function() end
@@ -109,6 +109,8 @@ local RECONFIGURE_OPTS
 local GLOBAL_QUERY_OPTS = { workspace = ngx.null, show_ws_id = true }
 
 local SERVER_HEADER = meta._SERVER_TOKENS
+local DEFAULT_PROXY_GRPC_VIA_HEADER = "2 " .. SERVER_HEADER
+local DEFAULT_PROXY_HTTP_VIA_HEADER = "1.1 " .. SERVER_HEADER
 
 
 local STREAM_TLS_TERMINATE_SOCK
@@ -912,6 +914,9 @@ return {
         reports.init_worker(kong.configuration)
       end
 
+      DEFAULT_PROXY_HTTP_VIA_HEADER = (tonumber(kong.configuration.proxy_http_version, 10) or "1.1")
+        .. " " .. SERVER_HEADER
+
       update_lua_mem(true)
 
       if kong.configuration.role == "control_plane" then
@@ -1290,13 +1295,9 @@ return {
       var.upstream_x_forwarded_path   = forwarded_path
       var.upstream_x_forwarded_prefix = forwarded_prefix
 
-      do
-        local req_via = get_header(constants.HEADERS.VIA, ctx)
-        local kong_inbound_via = protocol_version and protocol_version .. " " .. SERVER_HEADER
-                                 or SERVER_HEADER
-        var.upstream_via = req_via and req_via .. ", " .. kong_inbound_via
-                           or kong_inbound_via
-      end
+      local req_via = get_header(constants.HEADERS.VIA, ctx)
+      local kong_via = protocol_version and (protocol_version .. " " .. SERVER_HEADER) or SERVER_HEADER
+      var.upstream_via = req_via and (req_via .. ", " .. kong_via) or kong_via
 
       -- At this point, the router and `balancer_setup_stage1` have been
       -- executed; detect requests that need to be redirected from `proxy_pass`
@@ -1487,25 +1488,11 @@ return {
         end
 
         if enabled_headers[headers.VIA] then
-          -- Kong does not support injected directives like 'nginx_location_proxy_http_version',
-          -- so we skip checking them.
-
-          local proxy_http_version
-
           local upstream_scheme = var.upstream_scheme
-          if upstream_scheme == "grpc" or upstream_scheme == "grpcs" then
-            proxy_http_version = "2"
-          end
-          if not proxy_http_version then
-            proxy_http_version = ctx.proxy_http_version or
-                                 kong.configuration.proxy_http_version or
-                                 DEFAULT_PROXY_HTTP_VERSION
-          end
-
-          local kong_outbound_via = proxy_http_version .. " " .. SERVER_HEADER
-          local resp_via = var["upstream_http_" .. headers.VIA]
-          header[headers.VIA] = resp_via and resp_via .. ", " .. kong_outbound_via
-                                or kong_outbound_via
+          local resp_via = var.upstream_http_via
+          local kong_via = (upstream_scheme == "grpc" or upstream_scheme == "grpcs") and
+            DEFAULT_PROXY_GRPC_VIA_HEADER or DEFAULT_PROXY_HTTP_VIA_HEADER
+          header[headers.VIA] = resp_via and (resp_via .. ", " .. kong_via) or kong_via
         end
 
         -- If upstream does not provide the 'Server' header, an 'openresty' header