http: use Symbol for outgoing headers

PR-URL: #10941
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>

lib/_http_client.js

@@ -14,6 +14,7 @@ const OutgoingMessage = require('_http_outgoing').OutgoingMessage;
 const Agent = require('_http_agent');
 const Buffer = require('buffer').Buffer;
 const urlToOptions = require('internal/url').urlToOptions;
+const outHeadersKey = require('internal/http').outHeadersKey;
 
 // The actual list of disallowed characters in regexp form is more like:
 //    /[^A-Za-z0-9\-._~!$&'()*+,;=/:@]/
@@ -182,7 +183,7 @@ function ClientRequest(options, cb) {
                       'client');
     }
     self._storeHeader(self.method + ' ' + self.path + ' HTTP/1.1\r\n',
-                      self._headers);
+                      self[outHeadersKey]);
   }
 
   this._ended = false;
@@ -278,7 +279,7 @@ ClientRequest.prototype._implicitHeader = function _implicitHeader() {
     throw new Error('Can\'t render headers after they are sent to the client');
   }
   this._storeHeader(this.method + ' ' + this.path + ' HTTP/1.1\r\n',
-                    this._headers);
+                    this[outHeadersKey]);
 };
 
 ClientRequest.prototype.abort = function abort() {

lib/_http_outgoing.js

@@ -9,6 +9,8 @@ const Buffer = require('buffer').Buffer;
 const common = require('_http_common');
 const checkIsHttpToken = common._checkIsHttpToken;
 const checkInvalidHeaderChar = common._checkInvalidHeaderChar;
+const outHeadersKey = require('internal/http').outHeadersKey;
+const StorageObject = require('internal/querystring').StorageObject;
 
 const CRLF = common.CRLF;
 const debug = common.debug;
@@ -74,7 +76,7 @@ function OutgoingMessage() {
   this.socket = null;
   this.connection = null;
   this._header = null;
-  this._headers = null;
+  this[outHeadersKey] = null;
 
   this._onPendingData = null;
 }
@@ -201,7 +203,7 @@ function _storeHeader(firstLine, headers) {
   var value;
   var i;
   var j;
-  if (headers === this._headers) {
+  if (headers === this[outHeadersKey]) {
     for (key in headers) {
       var entry = headers[key];
       field = entry[0];
@@ -393,11 +395,11 @@ function validateHeader(msg, name, value) {
 OutgoingMessage.prototype.setHeader = function setHeader(name, value) {
   validateHeader(this, name, value);
 
-  if (!this._headers)
-    this._headers = {};
+  if (!this[outHeadersKey])
+    this[outHeadersKey] = {};
 
   const key = name.toLowerCase();
-  this._headers[key] = [name, value];
+  this[outHeadersKey][key] = [name, value];
 
   switch (key.length) {
     case 10:
@@ -421,9 +423,9 @@ OutgoingMessage.prototype.getHeader = function getHeader(name) {
     throw new TypeError('"name" argument must be a string');
   }
 
-  if (!this._headers) return;
+  if (!this[outHeadersKey]) return;
 
-  var entry = this._headers[name.toLowerCase()];
+  var entry = this[outHeadersKey][name.toLowerCase()];
   if (!entry)
     return;
   return entry[1];
@@ -432,13 +434,13 @@ OutgoingMessage.prototype.getHeader = function getHeader(name) {
 
 // Returns an array of the names of the current outgoing headers.
 OutgoingMessage.prototype.getHeaderNames = function getHeaderNames() {
-  return (this._headers ? Object.keys(this._headers) : []);
+  return (this[outHeadersKey] ? Object.keys(this[outHeadersKey]) : []);
 };
 
 
 // Returns a shallow copy of the current outgoing headers.
 OutgoingMessage.prototype.getHeaders = function getHeaders() {
-  const headers = this._headers;
+  const headers = this[outHeadersKey];
   const ret = new OutgoingHeaders();
   if (headers) {
     const keys = Object.keys(headers);
@@ -457,7 +459,7 @@ OutgoingMessage.prototype.hasHeader = function hasHeader(name) {
     throw new TypeError('"name" argument must be a string');
   }
 
-  return !!(this._headers && this._headers[name.toLowerCase()]);
+  return !!(this[outHeadersKey] && this[outHeadersKey][name.toLowerCase()]);
 };
 
 
@@ -491,8 +493,8 @@ OutgoingMessage.prototype.removeHeader = function removeHeader(name) {
       break;
   }
 
-  if (this._headers) {
-    delete this._headers[key];
+  if (this[outHeadersKey]) {
+    delete this[outHeadersKey][key];
   }
 };
 

lib/_http_server.js

@@ -13,6 +13,7 @@ const continueExpression = common.continueExpression;
 const chunkExpression = common.chunkExpression;
 const httpSocketSetup = common.httpSocketSetup;
 const OutgoingMessage = require('_http_outgoing').OutgoingMessage;
+const outHeadersKey = require('internal/http').outHeadersKey;
 
 const STATUS_CODES = exports.STATUS_CODES = {
   100: 'Continue',
@@ -179,7 +180,7 @@ function writeHead(statusCode, reason, obj) {
   this.statusCode = statusCode;
 
   var headers;
-  if (this._headers) {
+  if (this[outHeadersKey]) {
     // Slow-case: when progressive API and header fields are passed.
     var k;
     if (obj) {
@@ -196,7 +197,7 @@ function writeHead(statusCode, reason, obj) {
       }
     }
     // only progressive api is used
-    headers = this._headers;
+    headers = this[outHeadersKey];
   } else {
     // only writeHead() called
     headers = obj;

lib/internal/http.js

@@ -0,0 +1,5 @@
+'use strict';
+
+module.exports = {
+  outHeadersKey: Symbol('outHeadersKey')
+};

node.gyp

@@ -85,6 +85,7 @@
       'lib/internal/errors.js',
       'lib/internal/freelist.js',
       'lib/internal/fs.js',
+      'lib/internal/http.js',
       'lib/internal/linkedlist.js',
       'lib/internal/net.js',
       'lib/internal/module.js',