http: add rawPacket in err of clientError event

doc/api/http.md

@@ -765,6 +765,11 @@ object, so any HTTP response sent, including response headers and payload,
 *must* be written directly to the `socket` object. Care must be taken to
 ensure the response is a properly formatted HTTP response message.
 
+`err` is an instance of `Error` with two extra columns:
+
++ `bytesParsed`: the bytes count of request packet that Node.js may have parsed correctly;
++ `rawPacket`: the raw packet of current request.
+
 ### Event: 'close'
 <!-- YAML
 added: v0.1.4

lib/_http_server.js

@@ -475,7 +475,11 @@ function socketOnError(e) {
 function onParserExecuteCommon(server, socket, parser, state, ret, d) {
   resetSocketTimeout(server, socket, state);
 
+  if (!d)
+    d = parser.getCurrentBuffer();
+
   if (ret instanceof Error) {
+    ret.rawPacket = d;
     debug('parse error', ret);
     socketOnError.call(socket, ret);
   } else if (parser.incoming && parser.incoming.upgrade) {
@@ -484,9 +488,6 @@ function onParserExecuteCommon(server, socket, parser, state, ret, d) {
     var req = parser.incoming;
     debug('SERVER upgrade or connect', req.method);
 
-    if (!d)
-      d = parser.getCurrentBuffer();
-
     socket.removeListener('data', state.onData);
     socket.removeListener('end', state.onEnd);
     socket.removeListener('close', state.onClose);

test/parallel/test-http-server-client-error.js

@@ -10,6 +10,12 @@ const server = http.createServer(common.mustCall(function(req, res) {
 }));
 
 server.on('clientError', common.mustCall(function(err, socket) {
+  assert.strictEqual(err instanceof Error, true);
+  assert.strictEqual(err.code, 'HPE_INVALID_METHOD');
+  assert.strictEqual(err.bytesParsed, 1);
+  assert.strictEqual(err.message, 'Parse Error');
+  assert.strictEqual(err.rawPacket.toString(), 'Oopsie-doopsie\r\n');
+
   socket.end('HTTP/1.1 400 Bad Request\r\n\r\n');
 
   server.close();