Add some error reporting to the version method

cmd/minikube/cmd/start.go

@@ -479,8 +479,8 @@ func configureRuntimes(h *host.Host, runner bootstrapper.CommandRunner) cruntime
 	if err != nil {
 		exit.WithError("Failed to enable container runtime", err)
 	}
-	version := cr.Version()
+	version, err := cr.Version()
-	if version != "" {
+	if err == nil {
 		console.OutStyle(cr.Name(), "Version of container runtime is %s", version)
 	}
 	return cr

pkg/minikube/cruntime/containerd.go

@@ -35,18 +35,18 @@ func (r *Containerd) Name() string {
 }
 
 // Version retrieves the current version of this runtime
-func (r *Containerd) Version() string {
+func (r *Containerd) Version() (string, error) {
 	ver, err := r.Runner.CombinedOutput("containerd --version")
 	if err != nil {
-		return ""
+		return "", err
 	}
 
 	// containerd github.com/containerd/containerd v1.2.0 c4446665cb9c30056f4998ed953e6d4ff22c7c39
 	words := strings.Split(ver, " ")
 	if len(words) >= 4 && words[0] == "containerd" {
-		return strings.Replace(words[2], "v", "", 1)
+		return strings.Replace(words[2], "v", "", 1), nil
 	}
-	return ""
+	return "", fmt.Errorf("unknown version: %q", ver)
 }
 
 // SocketPath returns the path to the socket file for containerd

pkg/minikube/cruntime/crio.go

@@ -35,16 +35,16 @@ func (r *CRIO) Name() string {
 }
 
 // Version retrieves the current version of this runtime
-func (r *CRIO) Version() string {
+func (r *CRIO) Version() (string, error) {
 	ver, err := r.Runner.CombinedOutput("crio --version")
 	if err != nil {
-		return ""
+		return "", err
 	}
 
 	// crio version 1.13.0
 	// commit: ""
 	line := strings.Split(ver, "\n")[0]
-	return strings.Replace(line, "crio version ", "", 1)
+	return strings.Replace(line, "crio version ", "", 1), nil
 }
 
 // SocketPath returns the path to the socket file for CRIO

pkg/minikube/cruntime/cruntime.go

@@ -35,7 +35,7 @@ type Manager interface {
 	// Name is a human readable name for a runtime
 	Name() string
 	// Version retrieves the current version of this runtime
-	Version() string
+	Version() (string, error)
 	// Enable idempotently enables this runtime on a host
 	Enable() error
 	// Disable idempotently disables this runtime on a host

pkg/minikube/cruntime/docker.go

@@ -38,14 +38,14 @@ func (r *Docker) Name() string {
 }
 
 // Version retrieves the current version of this runtime
-func (r *Docker) Version() string {
+func (r *Docker) Version() (string, error) {
 	// Note: the server daemon has to be running, for this call to return successfully
 	ver, err := r.Runner.CombinedOutput("docker version --format '{{.Server.Version}}'")
 	if err != nil {
-		return ""
+		return "", err
 	}
 
-	return strings.Split(ver, "\n")[0]
+	return strings.Split(ver, "\n")[0], nil
 }
 
 // SocketPath returns the path to the socket file for Docker

pkg/minikube/cruntime/rkt.go

@@ -35,16 +35,16 @@ func (r *Rkt) Name() string {
 }
 
 // Version retrieves the current version of this runtime
-func (r *Rkt) Version() string {
+func (r *Rkt) Version() (string, error) {
 	ver, err := r.Runner.CombinedOutput("rkt version")
 	if err != nil {
-		return ""
+		return "", err
 	}
 
 	// rkt Version: 1.24.0
 	// appc Version: 0.8.10
 	line := strings.Split(ver, "\n")[0]
-	return strings.Replace(line, "rkt Version: ", "", 1)
+	return strings.Replace(line, "rkt Version: ", "", 1), nil
 }
 
 // SocketPath returns the path to the socket file for rkt/rktlet