Add hyperkit version

Makefile

@@ -329,7 +329,9 @@ out/docker-machine-driver-hyperkit:
 ifeq ($(MINIKUBE_BUILD_IN_DOCKER),y)
 	$(call DOCKER,$(HYPERKIT_BUILD_IMAGE),CC=o64-clang CXX=o64-clang++ /usr/bin/make $@)
 else
-	GOOS=darwin CGO_ENABLED=1 go build -o $(BUILD_DIR)/docker-machine-driver-hyperkit k8s.io/minikube/cmd/drivers/hyperkit
+	GOOS=darwin CGO_ENABLED=1 go build \
+		-ldflags "-X k8s.io/minikube/pkg/drivers/hyperkit.version=$(VERSION)" 	\
+		-o $(BUILD_DIR)/docker-machine-driver-hyperkit k8s.io/minikube/cmd/drivers/hyperkit
 endif
 
 .PHONY: install-hyperkit-driver

cmd/drivers/hyperkit/main.go

@@ -19,10 +19,18 @@ limitations under the License.
 package main
 
 import (
+	"fmt"
+	"os"
+
 	"github.com/docker/machine/libmachine/drivers/plugin"
 	"k8s.io/minikube/pkg/drivers/hyperkit"
 )
 
 func main() {
+	if len(os.Args) > 1 && os.Args[1] == "--version" {
+		fmt.Println(hyperkit.GetVersion())
+		return
+	}
+
 	plugin.RegisterDriver(hyperkit.NewDriver("", ""))
 }

docs/drivers.md

@@ -133,6 +133,14 @@ or, to use hyperkit as a default driver for minikube:
 minikube config set vm-driver hyperkit
 ```
 
+### Troubleshoot
+
+Make sure you are running the lastest version of your driver.
+
+```shell
+docker-machine-driver-hyperkit --version
+```
+
 ## HyperV driver
 
 Hyper-v users may need to create a new external network switch as described [here](https://docs.docker.com/machine/drivers/hyper-v/). This step may prevent a problem in which `minikube start` hangs indefinitely, unable to ssh into the minikube virtual machine. In this add, add the `--hyperv-virtual-switch=switch-name` argument to the `minikube start` command.

pkg/drivers/hyperkit/version.go

+/*
+Copyright 2016 The Kubernetes Authors All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package hyperkit
+
+// The current version of the docker-machine-driver-hyperkit
+
+// version is a private field and should be set when compiling with --ldflags="-X k8s.io/minikube/pkg/drivers/hyperkit.version=vX.Y.Z"
+var version = "v0.0.0-unset"
+
+// GetVersion returns the current docker-machine-driver-hyperkit version
+func GetVersion() string {
+	return version
+}