lib: add handling of EAGAIN error on connection

PR-URL: #281
Reviewed-By: Alexey Orlenko <eaglexrlnk@gmail.com>
Reviewed-By: Dmytro Nechai <nechaido@gmail.com>
Reviewed-By: Denys Otrishko <shishugi@gmail.com>

lib/socket.js

@@ -82,14 +82,23 @@ class Transport extends EventEmitter {
   }
 }
 
-const socketFactory = connect => (...options) => {
-  const callback = common.extractCallback(options);
-  const socket = connect(...options);
-  socket.once('error', callback);
-  socket.once('connect', () => {
-    socket.removeListener('error', callback);
-    callback(null, socket);
-  });
+const socketFactory = (connect) => {
+  const resultConnectFn = (...options) => {
+    const callback = common.extractCallback(options);
+    const socket = connect(...options);
+    socket.once('error', (error) => {
+      if (error.code !== 'EAGAIN') {
+        callback(error);
+        return;
+      }
+      process.nextTick(resultConnectFn, ...options, callback);
+    });
+    socket.once('connect', () => {
+      socket.removeListener('error', callback);
+      callback(null, socket);
+    });
+  };
+  return resultConnectFn;
 };
 
 // Create a function that will be bound to socketFactory that will