Add drivers.InstallOrUpdate acceptance tests

cmd/minikube/cmd/start.go

@@ -992,7 +992,7 @@ func validateDriverVersion(vmDriver string) {
 	case constants.DriverKvm2:
 		driverExecutable = fmt.Sprintf("docker-machine-driver-%s", constants.DriverKvm2)
 		targetDir := constants.MakeMiniPath("bin")
-		err := drivers.Download(driverExecutable, targetDir, minikubeVersion)
+		err := drivers.InstallOrUpdate(driverExecutable, targetDir, minikubeVersion)
 		if err != nil {
 			out.WarningT("Error downloading driver: {{.error}}", out.V{"error": err})
 		}

pkg/drivers/drivers.go

@@ -151,8 +151,8 @@ func fixPermissions(path string) error {
 	return nil
 }
 
-// Download downloads driver if it is not present, or if the version is old
-func Download(driver, destination string, minikubeVersion semver.Version) error {
+// InstallOrUpdate downloads driver if it is not present, or updates it if there's a newer version
+func InstallOrUpdate(driver, destination string, minikubeVersion semver.Version) error {
 	_, err := exec.LookPath(driver)
 	// if file driver doesn't exist, download it
 	if err != nil {

test/integration/driver_update_test.go

@@ -0,0 +1,69 @@
+/*
+Copyright 2019 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 integration
+
+import (
+	"fmt"
+	"io/ioutil"
+	"os"
+	"path"
+	"runtime"
+	"testing"
+
+	"github.com/blang/semver"
+
+	"k8s.io/minikube/pkg/drivers"
+)
+
+func TestDriverInstallOrUpdate(t *testing.T) {
+	if runtime.GOOS != "linux" {
+		t.Skip()
+	}
+
+	tests := []struct {
+		name string
+		path string
+	}{
+		{name: "driver-without-version-support", path: "./testdata/kvm2-driver-without-version"},
+		{name: "driver-with-older-version", path: "./testdata/kvm2-driver-without-version"},
+	}
+
+	for _, tc := range tests {
+		dir, err := ioutil.TempDir("", tc.name)
+		if err != nil {
+			t.Fatalf("Expected to create tempdir. test: %s, got: %v", tc.name, err)
+		}
+		defer os.RemoveAll(dir)
+
+		os.Setenv("PATH", fmt.Sprintf("%s:%s", tc.path, os.Getenv("PATH")))
+
+		newerVersion, err := semver.Make("1.1.3")
+		if err != nil {
+			t.Fatalf("Expected new semver. test: %v, got: %v", tc.name, err)
+		}
+
+		err = drivers.InstallOrUpdate("docker-machine-driver-kvm2", dir, newerVersion)
+		if err != nil {
+			t.Fatalf("Expected to update driver. test: %s, got: %v", tc.name, err)
+		}
+
+		_, err = os.Stat(path.Join(dir, "docker-machine-driver-kvm2"))
+		if err != nil {
+			t.Fatalf("Expected driver to be download. test: %s, got: %v", tc.name, err)
+		}
+	}
+}