De-lint everything and replace "go lint" with golangci-lint

.travis.yml

@@ -5,6 +5,8 @@ sudo: required
 go:
   - 1.x
 
+before_install:
+  - sudo apt-get install -y libvirt-dev
 install:
   - echo "Don't run anything."
 script:

Makefile

@@ -219,9 +219,25 @@ fmt:
 vet:
 	@go vet $(SOURCE_PACKAGES)
 
+# Once v1.16.1+ is released, replace with
+# curl -sfL https://install.goreleaser.com/github.com/golangci/golangci-lint.sh \
+#  | bash -s -- -b out/linters v1.16.0
+
+out/linters/golangci-lint:
+	mkdir -p out/linters \
+	  && cd out/linters \
+	  && test -f go.mod || go mod init linters \
+	  && go get -u github.com/golangci/golangci-lint/cmd/golangci-lint@692dacb773b703162c091c2d8c59f9cd2d6801db >/dev/null
+	cp -f $(GOPATH)/bin/golangci-lint out/linters/golangci-lint
+
 .PHONY: lint
-lint:
-	@golint -set_exit_status $(SOURCE_PACKAGES)
+lint: pkg/minikube/assets/assets.go out/linters/golangci-lint
+	./out/linters/golangci-lint run \
+	  --deadline 4m \
+	  --build-tags "${MINIKUBE_INTEGRATION_BUILD_TAGS}" \
+	  --enable goimports,gocritic,golint,gocyclo,interfacer,misspell,nakedret,stylecheck,unconvert,unparam \
+	  --exclude 'variable on range scope.*in function literal|ifElseChain' \
+	  ./...
 
 .PHONY: reportcard
 reportcard:

cmd/minikube/cmd/cache_list.go

@@ -56,16 +56,16 @@ For the list of accessible variables for the template, see the struct values her
 	cacheCmd.AddCommand(listCacheCmd)
 }
 
+// cacheList returns a formatted list of images found within the local cache
 func cacheList(images []string) error {
 	for _, image := range images {
 		tmpl, err := template.New("list").Parse(cacheListFormat)
 		if err != nil {
-			exit.WithError("Unable to parse template", err)
+			return err
 		}
 		listTmplt := CacheListTemplate{image}
-		err = tmpl.Execute(os.Stdout, listTmplt)
-		if err != nil {
-			exit.WithError("Unable to process template", err)
+		if err := tmpl.Execute(os.Stdout, listTmplt); err != nil {
+			return err
 		}
 	}
 	return nil

cmd/minikube/cmd/config/addons.go

@@ -17,6 +17,7 @@ limitations under the License.
 package config
 
 import (
+	"github.com/golang/glog"
 	"github.com/spf13/cobra"
 )
 
@@ -26,6 +27,8 @@ var AddonsCmd = &cobra.Command{
 	Short: "Modify minikube's kubernetes addons",
 	Long:  `addons modifies minikube addons files using subcommands like "minikube addons enable heapster"`,
 	Run: func(cmd *cobra.Command, args []string) {
-		cmd.Help()
+		if err := cmd.Help(); err != nil {
+			glog.Errorf("help: %v", err)
+		}
 	},
 }

cmd/minikube/cmd/config/config.go

@@ -23,6 +23,7 @@ import (
 	"os"
 	"strings"
 
+	"github.com/golang/glog"
 	"github.com/spf13/cobra"
 	"k8s.io/minikube/pkg/minikube/config"
 	"k8s.io/minikube/pkg/minikube/constants"
@@ -261,7 +262,9 @@ var ConfigCmd = &cobra.Command{
 	Long: `config modifies minikube config files using subcommands like "minikube config set vm-driver kvm"
 Configurable fields: ` + "\n\n" + configurableFields(),
 	Run: func(cmd *cobra.Command, args []string) {
-		cmd.Help()
+		if err := cmd.Help(); err != nil {
+			glog.Errorf("help: %v", err)
+		}
 	},
 }
 
@@ -344,12 +347,12 @@ func DeleteFromConfigMap(name string, images []string) error {
 func WriteConfig(m config.MinikubeConfig) error {
 	f, err := os.Create(constants.ConfigFile)
 	if err != nil {
-		return fmt.Errorf("Could not open file %s: %s", constants.ConfigFile, err)
+		return fmt.Errorf("create %s: %s", constants.ConfigFile, err)
 	}
 	defer f.Close()
 	err = encode(f, m)
 	if err != nil {
-		return fmt.Errorf("Error encoding config %s: %s", constants.ConfigFile, err)
+		return fmt.Errorf("encode %s: %s", constants.ConfigFile, err)
 	}
 	return nil
 }

cmd/minikube/cmd/config/open.go

@@ -95,9 +95,9 @@ You can add one by annotating a service with the label %s:%s`, key, addonName)
 		}
 		for i := range serviceList.Items {
 			svc := serviceList.Items[i].ObjectMeta.Name
-			service.WaitAndMaybeOpenService(api, namespace, svc, addonsURLTemplate,
-				addonsURLMode, https, wait, interval)
-
+			if err := service.WaitAndMaybeOpenService(api, namespace, svc, addonsURLTemplate, addonsURLMode, https, wait, interval); err != nil {
+				exit.WithCode(exit.Unavailable, "Wait failed: %v", err)
+			}
 		}
 	},
 }

cmd/minikube/cmd/config/prompt.go

@@ -23,6 +23,7 @@ import (
 	"os"
 	"strings"
 
+	"github.com/golang/glog"
 	"golang.org/x/crypto/ssh/terminal"
 	"k8s.io/minikube/pkg/minikube/console"
 )
@@ -42,15 +43,13 @@ func AskForYesNoConfirmation(s string, posResponses, negResponses []string) bool
 			log.Fatal(err)
 		}
 
-		response = strings.ToLower(strings.TrimSpace(response))
-
-		if containsString(posResponses, response) {
+		switch r := strings.ToLower(strings.TrimSpace(response)); {
+		case containsString(posResponses, r):
 			return true
-		} else if containsString(negResponses, response) {
+		case containsString(negResponses, r):
 			return false
-		} else {
+		default:
 			console.Err("Please type yes or no:")
-			return AskForYesNoConfirmation(s, posResponses, negResponses)
 		}
 	}
 }
@@ -112,7 +111,7 @@ func concealableAskForStaticValue(readWriter io.ReadWriter, promptString string,
 		response = strings.TrimSpace(response)
 		if len(response) == 0 {
 			console.Warning("Please enter a value:")
-			return concealableAskForStaticValue(readWriter, promptString, hidden)
+			continue
 		}
 		return response, nil
 	}
@@ -126,7 +125,11 @@ func AskForPasswordValue(s string) string {
 	if err != nil {
 		log.Fatal(err)
 	}
-	defer terminal.Restore(stdInFd, oldState)
+	defer func() {
+		if err := terminal.Restore(stdInFd, oldState); err != nil {
+			glog.Errorf("terminal restore failed: %v", err)
+		}
+	}()
 
 	result, err := concealableAskForStaticValue(os.Stdin, s, true)
 	if err != nil {

cmd/minikube/cmd/config/util.go

@@ -54,7 +54,7 @@ func findSetting(name string) (Setting, error) {
 			return s, nil
 		}
 	}
-	return Setting{}, fmt.Errorf("Property name %s not found", name)
+	return Setting{}, fmt.Errorf("property name %q not found", name)
 }
 
 // Set Functions

cmd/minikube/cmd/config/validations.go

@@ -33,14 +33,24 @@ import (
 	"k8s.io/minikube/pkg/minikube/cruntime"
 )
 
+// containerdOnlyMsg is the message shown when a containerd-only addon is enabled
+const containerdOnlyAddonMsg = `
+This addon can only be enabled with the containerd runtime backend. To enable this backend, please first stop minikube with:
+
+minikube stop
+
+and then start minikube again with the following flags:
+
+minikube start --container-runtime=containerd --docker-opt containerd=/var/run/containerd/containerd.sock`
+
 // IsValidDriver checks if a driver is supported
 func IsValidDriver(string, driver string) error {
 	for _, d := range constants.SupportedVMDrivers {
 		if driver == d {
 			return nil
 		}
 	}
-	return fmt.Errorf("Driver %s is not supported", driver)
+	return fmt.Errorf("driver %q is not supported", driver)
 }
 
 // RequiresRestartMsg returns the "requires restart" message
@@ -53,7 +63,7 @@ func RequiresRestartMsg(string, string) error {
 func IsValidDiskSize(name string, disksize string) error {
 	_, err := units.FromHumanSize(disksize)
 	if err != nil {
-		return fmt.Errorf("Not valid disk size: %v", err)
+		return fmt.Errorf("invalid disk size: %v", err)
 	}
 	return nil
 }
@@ -117,7 +127,7 @@ func IsPositive(name string, val string) error {
 func IsValidCIDR(name string, cidr string) error {
 	_, _, err := net.ParseCIDR(cidr)
 	if err != nil {
-		return fmt.Errorf("Error parsing CIDR: %v", err)
+		return fmt.Errorf("invalid CIDR: %v", err)
 	}
 	return nil
 }
@@ -151,16 +161,7 @@ func IsContainerdRuntime(_, _ string) error {
 	}
 	_, ok := r.(*cruntime.Containerd)
 	if !ok {
-		return fmt.Errorf(`This addon can only be enabled with the containerd runtime backend.
-
-To enable this backend, please first stop minikube with:
-
-minikube stop
-
-and then start minikube again with the following flags:
-
-minikube start --container-runtime=containerd --docker-opt containerd=/var/run/containerd/containerd.sock`)
+		return fmt.Errorf(containerdOnlyAddonMsg)
 	}
-
 	return nil
 }

cmd/minikube/cmd/env.go

@@ -377,7 +377,9 @@ var dockerEnvCmd = &cobra.Command{
 			}
 		}
 
-		executeTemplateStdout(shellCfg)
+		if err := executeTemplateStdout(shellCfg); err != nil {
+			exit.WithError("Error executing template", err)
+		}
 	},
 }
 

cmd/minikube/cmd/root.go

@@ -86,7 +86,9 @@ var RootCmd = &cobra.Command{
 
 		logDir := pflag.Lookup("log_dir")
 		if !logDir.Changed {
-			logDir.Value.Set(constants.MakeMiniPath("logs"))
+			if err := logDir.Value.Set(constants.MakeMiniPath("logs")); err != nil {
+				exit.WithError("logdir set failed", err)
+			}
 		}
 
 		if enableUpdateNotification {
@@ -116,7 +118,9 @@ func setFlagsUsingViper() {
 		}
 		// Viper will give precedence first to calls to the Set command,
 		// then to values from the config.yml
-		a.Value.Set(viper.GetString(a.Name))
+		if err := a.Value.Set(viper.GetString(a.Name)); err != nil {
+			exit.WithError(fmt.Sprintf("failed to set value for %q", a.Name), err)
+		}
 		a.Changed = true
 	}
 }
@@ -129,7 +133,9 @@ func init() {
 	RootCmd.AddCommand(configCmd.AddonsCmd)
 	RootCmd.AddCommand(configCmd.ProfileCmd)
 	pflag.CommandLine.AddGoFlagSet(goflag.CommandLine)
-	viper.BindPFlags(RootCmd.PersistentFlags())
+	if err := viper.BindPFlags(RootCmd.PersistentFlags()); err != nil {
+		exit.WithError("Unable to bind flags", err)
+	}
 
 	cobra.OnInitialize(initConfig)
 
@@ -176,7 +182,7 @@ func GetClusterBootstrapper(api libmachine.API, bootstrapperName string) (bootst
 			return nil, errors.Wrap(err, "getting kubeadm bootstrapper")
 		}
 	default:
-		return nil, fmt.Errorf("Unknown bootstrapper: %s", bootstrapperName)
+		return nil, fmt.Errorf("unknown bootstrapper: %s", bootstrapperName)
 	}
 
 	return b, nil

cmd/minikube/cmd/root_test.go

@@ -22,6 +22,7 @@ import (
 	"strings"
 	"testing"
 
+	"github.com/pkg/errors"
 	"github.com/spf13/cobra"
 	"github.com/spf13/pflag"
 	"github.com/spf13/viper"
@@ -145,37 +146,43 @@ func getEnvVarName(name string) string {
 	return constants.MinikubeEnvPrefix + "_" + strings.ToUpper(name)
 }
 
-func setValues(t *testing.T, tt configTest) {
+func setValues(tt configTest) error {
 	if tt.FlagValue != "" {
-		pflag.Set(tt.Name, tt.FlagValue)
+		if err := pflag.Set(tt.Name, tt.FlagValue); err != nil {
+			return errors.Wrap(err, "flag set")
+		}
 	}
 	if tt.EnvValue != "" {
 		s := strings.Replace(getEnvVarName(tt.Name), "-", "_", -1)
 		os.Setenv(s, tt.EnvValue)
 	}
 	if tt.ConfigValue != "" {
-		err := initTestConfig(tt.ConfigValue)
-		if err != nil {
-			t.Fatalf("Config %s not read correctly: %v", tt.ConfigValue, err)
+		if err := initTestConfig(tt.ConfigValue); err != nil {
+			return errors.Wrapf(err, "Config %s not read correctly", tt.ConfigValue)
 		}
 	}
+	return nil
 }
 
-func unsetValues(tt configTest) {
-	var f = pflag.Lookup(tt.Name)
-	f.Value.Set(f.DefValue)
+func unsetValues(name string) error {
+	f := pflag.Lookup(name)
+	if err := f.Value.Set(f.DefValue); err != nil {
+		return errors.Wrapf(err, "set(%s)", f.DefValue)
+	}
 	f.Changed = false
-
-	os.Unsetenv(getEnvVarName(tt.Name))
-
+	os.Unsetenv(getEnvVarName(name))
 	viper.Reset()
+	return nil
 }
 
 func TestViperAndFlags(t *testing.T) {
 	restore := hideEnv(t)
 	defer restore(t)
 	for _, tt := range configTests {
-		setValues(t, tt)
+		err := setValues(tt)
+		if err != nil {
+			t.Fatalf("setValues: %v", err)
+		}
 		setupViper()
 		f := pflag.Lookup(tt.Name)
 		if f == nil {
@@ -185,6 +192,9 @@ func TestViperAndFlags(t *testing.T) {
 		if actual != tt.ExpectedValue {
 			t.Errorf("pflag.Value(%s) => %s, wanted %s [%+v]", tt.Name, actual, tt.ExpectedValue, tt)
 		}
-		unsetValues(tt)
+		// Some flag validation may not accept their default value, such as log_at_backtrace :(
+		if err := unsetValues(tt.Name); err != nil {
+			t.Logf("unsetValues(%s) failed: %v", tt.Name, err)
+		}
 	}
 }

cmd/minikube/cmd/service_list.go

@@ -22,7 +22,7 @@ import (
 
 	"github.com/olekukonko/tablewriter"
 	"github.com/spf13/cobra"
-	"k8s.io/api/core/v1"
+	core "k8s.io/api/core/v1"
 	"k8s.io/minikube/pkg/minikube/console"
 	"k8s.io/minikube/pkg/minikube/exit"
 	"k8s.io/minikube/pkg/minikube/machine"
@@ -69,6 +69,6 @@ var serviceListCmd = &cobra.Command{
 }
 
 func init() {
-	serviceListCmd.Flags().StringVarP(&serviceListNamespace, "namespace", "n", v1.NamespaceAll, "The services namespace")
+	serviceListCmd.Flags().StringVarP(&serviceListNamespace, "namespace", "n", core.NamespaceAll, "The services namespace")
 	serviceCmd.AddCommand(serviceListCmd)
 }