http: wait for both prefinish/end to keepalive

When `free`ing the socket to be reused in keep-alive Agent wait for
both `prefinish` and `end` events. Otherwise the next request may be
written before the previous one has finished sending the body, leading
to a parser errors.

PR-URL: https://github.com/nodejs/node/pull/7149
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

1 files changed, 24 insertions, 3 deletions

diff --git a/lib/_http_client.js b/lib/_http_client.js
index 68eb125e0e..91855e5b87 100644
--- a/lib/_http_client.js
+++ b/lib/_http_client.js
@@ -195,6 +195,8 @@ function ClientRequest(options, cb) {
     self._flush();
     self = null;
   });
+
+  this._ended = false;
 }
 
 util.inherits(ClientRequest, OutgoingMessage);
@@ -466,6 +468,7 @@ function parserOnIncomingClient(res, shouldKeepAlive) {
 
   // add our listener first, so that we guarantee socket cleanup
   res.on('end', responseOnEnd);
+  req.on('prefinish', requestOnPrefinish);
   var handled = req.emit('response', res);
 
   // If the user did not listen for the 'response' event, then they
@@ -478,9 +481,7 @@ function parserOnIncomingClient(res, shouldKeepAlive) {
 }
 
 // client
-function responseOnEnd() {
-  var res = this;
-  var req = res.req;
+function responseKeepAlive(res, req) {
   var socket = req.socket;
 
   if (!req.shouldKeepAlive) {
@@ -504,6 +505,26 @@ function responseOnEnd() {
   }
 }
 
+function responseOnEnd() {
+  const res = this;
+  const req = this.req;
+
+  req._ended = true;
+  if (!req.shouldKeepAlive || req.finished)
+    responseKeepAlive(res, req);
+}
+
+function requestOnPrefinish() {
+  const req = this;
+  const res = this.res;
+
+  if (!req.shouldKeepAlive)
+    return;
+
+  if (req._ended)
+    responseKeepAlive(res, req);
+}
+
 function emitFreeNT(socket) {
   socket.emit('free');
 }