Fixing file:// uri issue for --iso-url flag

pkg/minikube/cluster/cluster.go

@@ -26,6 +26,7 @@ import (
 	"io/ioutil"
 	"net"
 	"net/http"
+	"net/url"
 	"os"
 	"path/filepath"
 	"strings"
@@ -51,6 +52,8 @@ var (
 	certs = []string{"ca.crt", "ca.key", "apiserver.crt", "apiserver.key"}
 )
 
+const fileScheme = "file"
+
 //This init function is used to set the logtostderr variable to false so that INFO level log info does not clutter the CLI
 //INFO lvl logging is displayed due to the kubernetes api calling flag.Set("logtostderr", "true") in its init()
 //see: https://github.com/kubernetes/kubernetes/blob/master/pkg/util/logs.go#L32-34
@@ -350,14 +353,14 @@ func engineOptions(config MachineConfig) *engine.Options {
 
 func createVirtualboxHost(config MachineConfig) drivers.Driver {
 	d := virtualbox.NewDriver(constants.MachineName, constants.Minipath)
-	d.Boot2DockerURL = config.GetISOCacheFileURI()
+	d.Boot2DockerURL = config.GetISOFileURI()
 	d.Memory = config.Memory
 	d.CPU = config.CPUs
 	d.DiskSize = int(config.DiskSize)
 	return d
 }
 
-func (m *MachineConfig) CacheMinikubeISO() error {
+func (m *MachineConfig) CacheMinikubeISOFromURL() error {
 	// store the miniube-iso inside the .minikube dir
 	response, err := http.Get(m.MinikubeISO)
 	if err != nil {
@@ -376,16 +379,38 @@ func (m *MachineConfig) CacheMinikubeISO() error {
 	return nil
 }
 
+func (m *MachineConfig) ShouldCacheMinikubeISO() bool {
+	// store the miniube-iso inside the .minikube dir
+
+	urlObj, err := url.Parse(m.MinikubeISO)
+	if err != nil {
+		return false
+	}
+	if urlObj.Scheme == fileScheme {
+		return false
+	}
+	if m.IsMinikubeISOCached() {
+		return false
+	}
+	return true
+}
+
 func (m *MachineConfig) GetISOCacheFilepath() string {
 	return filepath.Join(constants.Minipath, "cache", "iso", filepath.Base(m.MinikubeISO))
 }
 
-func (m *MachineConfig) GetISOCacheFileURI() string {
+func (m *MachineConfig) GetISOFileURI() string {
+	urlObj, err := url.Parse(m.MinikubeISO)
+	if err != nil {
+		return m.MinikubeISO
+	}
+	if urlObj.Scheme == fileScheme {
+		return m.MinikubeISO
+	}
 	isoPath := filepath.Join(constants.Minipath, "cache", "iso", filepath.Base(m.MinikubeISO))
 	// As this is a file URL there should be no backslashes regardless of platform running on.
 	return "file://" + filepath.ToSlash(isoPath)
 }
-
 func (m *MachineConfig) IsMinikubeISOCached() bool {
 	if _, err := os.Stat(m.GetISOCacheFilepath()); os.IsNotExist(err) {
 		return false
@@ -396,8 +421,8 @@ func (m *MachineConfig) IsMinikubeISOCached() bool {
 func createHost(api libmachine.API, config MachineConfig) (*host.Host, error) {
 	var driver interface{}
 
-	if !config.IsMinikubeISOCached() {
-		if err := config.CacheMinikubeISO(); err != nil {
+	if config.ShouldCacheMinikubeISO() {
+		if err := config.CacheMinikubeISOFromURL(); err != nil {
 			return nil, err
 		}
 	}

pkg/minikube/cluster/cluster_darwin.go

@@ -24,7 +24,7 @@ import (
 
 func createVMwareFusionHost(config MachineConfig) drivers.Driver {
 	d := vmwarefusion.NewDriver(constants.MachineName, constants.Minipath).(*vmwarefusion.Driver)
-	d.Boot2DockerURL = config.GetISOCacheFileURI()
+	d.Boot2DockerURL = config.GetISOFileURI()
 	d.Memory = config.Memory
 	d.CPU = config.CPUs
 
@@ -59,7 +59,7 @@ func createXhyveHost(config MachineConfig) *xhyveDriver {
 		},
 		Memory:         config.Memory,
 		CPU:            config.CPUs,
-		Boot2DockerURL: config.GetISOCacheFileURI(),
+		Boot2DockerURL: config.GetISOFileURI(),
 		BootCmd:        "loglevel=3 user=docker console=ttyS0 console=tty0 noembed nomodeset norestore waitusb=10 base host=boot2docker",
 		DiskSize:       int64(config.DiskSize),
 	}

pkg/minikube/cluster/cluster_linux.go

@@ -49,7 +49,7 @@ func createKVMHost(config MachineConfig) *kvmDriver {
 		CPU:            config.CPUs,
 		Network:        "default",
 		PrivateNetwork: "docker-machines",
-		Boot2DockerURL: config.GetISOCacheFileURI(),
+		Boot2DockerURL: config.GetISOFileURI(),
 		DiskSize:       config.DiskSize,
 		DiskPath:       filepath.Join(constants.Minipath, "machines", constants.MachineName, fmt.Sprintf("%s.img", constants.MachineName)),
 		ISO:            filepath.Join(constants.Minipath, "machines", constants.MachineName, "boot2docker.iso"),