http: simplify drain()

Simplify and slightly optimize draining outgoing http streams. Avoid
extra event listener and inline with rest of the drain logic.

PR-URL: https://github.com/nodejs/node/pull/29081
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>

1 files changed, 7 insertions, 5 deletions

diff --git a/lib/_http_server.js b/lib/_http_server.js
index b083983c94..2c48ab9191 100644
--- a/lib/_http_server.js
+++ b/lib/_http_server.js
@@ -32,7 +32,6 @@ const {
   CRLF,
   continueExpression,
   chunkExpression,
-  httpSocketSetup,
   kIncomingMessage,
   HTTPParser,
   _checkInvalidHeaderChar: checkInvalidHeaderChar,
@@ -41,7 +40,7 @@ const {
 const { OutgoingMessage } = require('_http_outgoing');
 const {
   kOutHeaders,
-  ondrain,
+  kNeedDrain,
   nowDate,
   emitStatistics
 } = require('internal/http');
@@ -359,8 +358,6 @@ function connectionListener(socket) {
 function connectionListenerInternal(server, socket) {
   debug('SERVER new http connection');
 
-  httpSocketSetup(socket);
-
   // Ensure that the server property of the socket is correctly set.
   // See https://github.com/nodejs/node/issues/13435
   if (socket.server === null)
@@ -455,6 +452,12 @@ function socketOnDrain(socket, state) {
       socket.parser.resume();
     socket.resume();
   }
+
+  const msg = socket._httpMessage;
+  if (msg && !msg.finished && msg[kNeedDrain]) {
+    msg[kNeedDrain] = false;
+    msg.emit('drain');
+  }
 }
 
 function socketOnTimeout() {
@@ -581,7 +584,6 @@ function onParserExecuteCommon(server, socket, parser, state, ret, d) {
     socket.removeListener('end', state.onEnd);
     socket.removeListener('close', state.onClose);
     socket.removeListener('drain', state.onDrain);
-    socket.removeListener('drain', ondrain);
     socket.removeListener('error', socketOnError);
     socket.removeListener('timeout', socketOnTimeout);
     unconsume(parser, socket);