http: removed headers stay removed

This allows automatically-inserted headers to be removed permanently by
calling OutgoingMessage.removeHeader() on them, as if they were normal
headers.

Author: James Halliday

lib/_http_outgoing.js

@@ -38,6 +38,13 @@ var contentLengthExpression = /Content-Length/i;
 var dateExpression = /Date/i;
 var expectExpression = /Expect/i;
 
+var automaticHeaders = {
+  connection: true,
+  'content-length': true,
+  'transfer-encoding': true,
+  date: true
+};
+
 
 var dateCache;
 function utcDate() {
@@ -68,6 +75,7 @@ function OutgoingMessage() {
   this.shouldKeepAlive = true;
   this.useChunkedEncodingByDefault = true;
   this.sendDate = false;
+  this._removedHeader = {};
 
   this._hasBody = true;
   this._trailer = '';
@@ -245,7 +253,10 @@ OutgoingMessage.prototype._storeHeader = function(firstLine, headers) {
   }
 
   // keep-alive logic
-  if (state.sentConnectionHeader === false) {
+  if (this._removedHeader.connection) {
+    this._last = true;
+    this.shouldKeepAlive = false;
+  } else if (state.sentConnectionHeader === false) {
     var shouldSendKeepAlive = this.shouldKeepAlive &&
         (state.sentContentLengthHeader ||
          this.useChunkedEncodingByDefault ||
@@ -260,7 +271,7 @@ OutgoingMessage.prototype._storeHeader = function(firstLine, headers) {
 
   if (state.sentContentLengthHeader == false &&
       state.sentTransferEncodingHeader == false) {
-    if (this._hasBody) {
+    if (this._hasBody && !this._removedHeader['transfer-encoding']) {
       if (this.useChunkedEncodingByDefault) {
         state.messageHeader += 'Transfer-Encoding: chunked\r\n';
         this.chunkedEncoding = true;
@@ -325,6 +336,10 @@ OutgoingMessage.prototype.setHeader = function(name, value) {
   this._headerNames = this._headerNames || {};
   this._headers[key] = value;
   this._headerNames[key] = name;
+
+  if (automaticHeaders[key]) {
+    this._removedHeader[key] = false;
+  }
 };
 
 
@@ -349,11 +364,17 @@ OutgoingMessage.prototype.removeHeader = function(name) {
     throw new Error('Can\'t remove headers after they are sent.');
   }
 
-  if (!this._headers) return;
-
   var key = name.toLowerCase();
-  delete this._headers[key];
-  delete this._headerNames[key];
+
+  if (key === 'date')
+    this.sendDate = false;
+  else if (automaticHeaders[key])
+    this._removedHeader[key] = true;
+
+  if (this._headers) {
+    delete this._headers[key];
+    delete this._headerNames[key];
+  }
 };
 
 

test/simple/test-http-remove-header-stays-removed.js

@@ -0,0 +1,59 @@
+// Copyright Joyent, Inc. and other Node contributors.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a
+// copy of this software and associated documentation files (the
+// "Software"), to deal in the Software without restriction, including
+// without limitation the rights to use, copy, modify, merge, publish,
+// distribute, sublicense, and/or sell copies of the Software, and to permit
+// persons to whom the Software is furnished to do so, subject to the
+// following conditions:
+//
+// The above copyright notice and this permission notice shall be included
+// in all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
+// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
+// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
+// USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+var common = require('../common');
+var assert = require('assert');
+
+var http = require('http');
+
+var server = http.createServer(function(request, response) {
+  // removed headers should stay removed, even if node automatically adds them
+  // to the output:
+  response.removeHeader('connection');
+  response.removeHeader('transfer-encoding');
+
+  // make sure that removing and then setting still works:
+  response.removeHeader('date');
+  response.setHeader('date', 'coffee o clock');
+
+  response.end('beep boop\n');
+
+  this.close();
+});
+
+var response = '';
+
+process.on('exit', function() {
+  assert.equal('beep boop\n', response);
+  console.log('ok');
+});
+
+server.listen(common.PORT, function() {
+  http.get({ port: common.PORT }, function(res) {
+    assert.equal(200, res.statusCode);
+    assert.deepEqual(res.headers, { date : 'coffee o clock' });
+
+    res.setEncoding('ascii');
+    res.on('data', function(chunk) {
+      response += chunk;
+    });
+  });
+});