http: close connection on 204 and chunked encoding

This is similar to commit 2cbf458 but this time for 204 No Content
instead of 304 Not Modified responses.

When the user sends a 204 response with a Transfer-Encoding: chunked
header, suppress sending the zero chunk and force the connection to
close.

lib/http.js

@@ -564,18 +564,22 @@ OutgoingMessage.prototype._storeHeader = function(firstLine, headers) {
     state.messageHeader += 'Date: ' + utcDate() + CRLF;
   }
 
-  // Force the connection to close when the response is a 304 Not Modified
-  // and the user has set a "Transfer-Encoding: chunked" header.
+  // Force the connection to close when the response is a 204 No Content or
+  // a 304 Not Modified and the user has set a "Transfer-Encoding: chunked"
+  // header.
   //
-  // RFC 2616 mandates that 304 responses MUST NOT have a body but node.js
-  // used to send out a zero chunk anyway to accommodate clients that don't
-  // have special handling for 304 responses.
+  // RFC 2616 mandates that 204 and 304 responses MUST NOT have a body but
+  // node.js used to send out a zero chunk anyway to accommodate clients
+  // that don't have special handling for those responses.
   //
   // It was pointed out that this might confuse reverse proxies to the point
   // of creating security liabilities, so suppress the zero chunk and force
   // the connection to close.
-  if (this.statusCode === 304 && this.chunkedEncoding === true) {
-    debug('304 response should not use chunked encoding, closing connection.');
+  var statusCode = this.statusCode;
+  if ((statusCode == 204 || statusCode === 304) &&
+      this.chunkedEncoding === true) {
+    debug(statusCode + ' response should not use chunked encoding,' +
+          ' closing connection.');
     this.chunkedEncoding = false;
     this.shouldKeepAlive = false;
   }

test/simple/test-http-chunked-304.js

@@ -24,32 +24,40 @@ var assert = require('assert');
 var http = require('http');
 var net = require('net');
 
-// RFC 2616, section 10.3.5:
+// RFC 2616, section 10.2.5:
 //
-//   The 304 response MUST NOT contain a message-body, and thus is always
+//   The 204 response MUST NOT contain a message-body, and thus is always
 //   terminated by the first empty line after the header fields.
 //
-// Verify that no empty chunk is sent when the user explicitly sets
-// a Transfer-Encoding header.
-var server = http.createServer(function(req, res) {
-  res.writeHead(304, { 'Transfer-Encoding': 'chunked' });
-  res.end();
-  server.close();
+// Likewise for 304 responses. Verify that no empty chunk is sent when
+// the user explicitly sets a Transfer-Encoding header.
+
+test(204, function() {
+  test(304);
 });
 
-server.listen(common.PORT, function() {
-  var conn = net.createConnection(common.PORT, function() {
-    conn.write('GET / HTTP/1.1\r\n\r\n');
+function test(statusCode, next) {
+  var server = http.createServer(function(req, res) {
+    res.writeHead(statusCode, { 'Transfer-Encoding': 'chunked' });
+    res.end();
+    server.close();
+  });
 
-    var resp = '';
-    conn.setEncoding('utf8');
-    conn.on('data', function(data) {
-      resp += data;
-    });
+  server.listen(common.PORT, function() {
+    var conn = net.createConnection(common.PORT, function() {
+      conn.write('GET / HTTP/1.1\r\n\r\n');
 
-    conn.on('end', common.mustCall(function() {
-      assert.equal(/^Connection: close\r\n$/m.test(resp), true);
-      assert.equal(/^0\r\n$/m.test(resp), false);
-    }));
+      var resp = '';
+      conn.setEncoding('utf8');
+      conn.on('data', function(data) {
+        resp += data;
+      });
+
+      conn.on('end', common.mustCall(function() {
+        assert.equal(/^Connection: close\r\n$/m.test(resp), true);
+        assert.equal(/^0\r\n$/m.test(resp), false);
+        if (next) process.nextTick(next);
+      }));
+    });
   });
-});
+}