http: overridable `clientError`

Make default `clientError` behavior (close socket immediately)
overridable. With this APIs it is possible to write a custom error
handler, and to send, for example, a 400 HTTP response.

    http.createServer(...).on('clientError', function(err, socket) {
      socket.end('HTTP/1.1 400 Bad Request\r\n\r\n');
      socket.destroy();
    });

Fix: #4543
PR-URL: https://github.com/nodejs/node/pull/4557
Reviewed-By: Brian White <mscdex@mscdex.net>

1 files changed, 39 insertions, 0 deletions

diff --git a/test/parallel/test-http-server-client-error.js b/test/parallel/test-http-server-client-error.js
new file mode 100644
index 0000000000..619a4c4517
--- /dev/null
+++ b/test/parallel/test-http-server-client-error.js
@@ -0,0 +1,39 @@
+'use strict';
+const common = require('../common');
+const assert = require('assert');
+
+const http = require('http');
+const net = require('net');
+
+const server = http.createServer(common.mustCall(function(req, res) {
+  res.end();
+}));
+
+server.on('clientError', common.mustCall(function(err, socket) {
+  socket.end('HTTP/1.1 400 Bad Request\r\n\r\n');
+
+  server.close();
+}));
+
+server.listen(common.PORT, function() {
+  function next() {
+    // Invalid request
+    const client = net.connect(common.PORT);
+    client.end('Oopsie-doopsie\r\n');
+
+    var chunks = '';
+    client.on('data', function(chunk) {
+      chunks += chunk;
+    });
+    client.once('end', function() {
+      assert.equal(chunks, 'HTTP/1.1 400 Bad Request\r\n\r\n');
+    });
+  }
+
+  // Normal request
+  http.get({ port: common.PORT, path: '/' }, function(res) {
+    assert.equal(res.statusCode, 200);
+    res.resume();
+    res.once('end', next);
+  });
+});