chore: add lint to GH actions CI

.github/workflows/develop.yaml

@@ -23,3 +23,5 @@ jobs:
         run:  make test
       - name: Build
         run:  make build
+      - name: Lint
+        run: make check

.github/workflows/main.yaml

@@ -23,3 +23,5 @@ jobs:
         run:  make test
       - name: Build
         run:  make build
+      - name: Lint
+        run: make check

.github/workflows/pull_requests.yaml

@@ -13,3 +13,5 @@ jobs:
         run:  make test
       - name: Build
         run:  make build
+      - name: Lint
+        run: make check

Makefile

@@ -58,6 +58,12 @@ latest:
 	# (run by CI only for releases)
 	docker push $(REPO):latest
 
+bin/golangci-lint:
+	curl -sSfL https://raw.githubusercontent.com/golangci/golangci-lint/master/install.sh | sh -s -- -b ./bin v1.27.0
+
+check: bin/golangci-lint
+	./bin/golangci-lint run --enable=unconvert,prealloc,bodyclose
+
 clean:
 	rm -f $(WINDOWS) $(LINUX) $(DARWIN)
 	-@rm -f coverage.out

appsody/builder.go

@@ -61,7 +61,8 @@ func (n *Builder) Build(name, runtime, path string) (image string, err error) {
 	err = cmd.Run()
 	if err != nil {
 		// TODO: sanitize stderr from appsody, or submit a PR to remove duplicates etc.
-		err = errors.New(fmt.Sprintf("%v. %v", string(stderr.Bytes()), err.Error()))
+		err = fmt.Errorf("%v. %v", stderr.String(), err.Error())
+		return
 	}
 
 	// remove the superfluous app-deploy.yaml
@@ -69,7 +70,7 @@ func (n *Builder) Build(name, runtime, path string) (image string, err error) {
 	if _, err = os.Stat(cfg); err == nil {
 		err = os.Remove(cfg)
 		if err != nil {
-			fmt.Fprintf(os.Stderr, fmt.Sprintf("unable to remove superfluous appsody config: %v\n", err))
+			fmt.Fprintf(os.Stderr,"unable to remove superfluous appsody config: %v\n", err)
 		}
 	}
 	return

appsody/initializer.go

@@ -52,11 +52,11 @@ func (n *Initializer) Initialize(name, runtime, path string) error {
 	stackName, ok := StackShortNames[runtime]
 	if !ok {
 		runtimes := []string{}
-		for k, _ := range StackShortNames {
+		for k := range StackShortNames {
 			runtimes = append(runtimes, k)
 		}
 
-		return errors.New(fmt.Sprintf("Unrecognized runtime '%v'.  Please choose one: %v.", runtime, strings.Join(runtimes, ", ")))
+		return fmt.Errorf("Unrecognized runtime '%v'.  Please choose one: %v.", runtime, strings.Join(runtimes, ", "))
 	}
 
 	// set up the command, specifying a sanitized project name and connecting
@@ -78,7 +78,7 @@ func (n *Initializer) Initialize(name, runtime, path string) error {
 	err = cmd.Run()
 	if err != nil {
 		// TODO: sanitize stderr from appsody, or submit a PR to remove duplicates etc.
-		err = errors.New(fmt.Sprintf("%v. %v", string(stderr.Bytes()), err.Error()))
+		err = fmt.Errorf("%v. %v", stderr.String(), err.Error())
 	}
 	return err
 }

client.go

@@ -343,7 +343,7 @@ func (c *Client) Update(root string) (err error) {
 
 	if !f.Initialized() {
 		// TODO: this needs a test.
-		return errors.New(fmt.Sprintf("the given path '%v' does not contain an initialized Function.  Please create one at this path before updating.", root))
+		return fmt.Errorf("the given path '%v' does not contain an initialized Function.  Please create one at this path before updating.", root)
 	}
 
 	// Build an image from the current state of the service function's implementation.
@@ -373,7 +373,7 @@ func (c *Client) Run(root string) error {
 
 	if !f.Initialized() {
 		// TODO: this needs a test.
-		return errors.New(fmt.Sprintf("the given path '%v' does not contain an initialized Function.  Please create one at this path in order to run.", root))
+		return fmt.Errorf("the given path '%v' does not contain an initialized Function.  Please create one at this path in order to run.", root)
 	}
 
 	// delegate to concrete implementation of runner entirely.
@@ -400,7 +400,7 @@ func (c *Client) Describe(name, root string) (fd FunctionDescription, err error)
 		return fd, err
 	}
 	if !f.Initialized() {
-		return fd, errors.New(fmt.Sprintf("%v is not initialized", f.name))
+		return fd, fmt.Errorf("%v is not initialized", f.name)
 	}
 	return c.describer.Describe(f.name)
 }
@@ -419,7 +419,7 @@ func (c *Client) Remove(name, root string) error {
 		return err
 	}
 	if !f.Initialized() {
-		return errors.New(fmt.Sprintf("%v is not initialized", f.name))
+		return fmt.Errorf("%v is not initialized", f.name)
 	}
 	return c.remover.Remove(f.name)
 }

client_test.go

@@ -1,7 +1,6 @@
 package faas_test
 
 import (
-	"errors"
 	"fmt"
 	"os"
 	"path/filepath"
@@ -45,7 +44,10 @@ func TestCreate(t *testing.T) {
 
 	// Create the test function root
 	root := "testdata/example.com/admin"
-	os.MkdirAll(root, 0700)
+	err = os.MkdirAll(root, 0700)
+	if err != nil {
+		panic(err)
+	}
 	defer os.RemoveAll(root)
 
 	// A supported langauge should not error
@@ -61,7 +63,10 @@ func TestCreateUnderivableName(t *testing.T) {
 
 	// Create the test function root
 	root := "testdata/example.com/admin"
-	os.MkdirAll(root, 0700)
+	err := os.MkdirAll(root, 0700)
+	if err != nil {
+		panic(err)
+	}
 	defer os.RemoveAll(root)
 
 	// Instantiation without an explicit service name, but no derivable service
@@ -127,7 +132,10 @@ func TestCreateDelegates(t *testing.T) {
 	)
 
 	// Create the test function root
-	os.MkdirAll(root, 0700)
+	err := os.MkdirAll(root, 0700)
+	if err != nil {
+		panic(err)
+	}
 	defer os.RemoveAll(root)
 
 	client, err := faas.New(
@@ -166,7 +174,7 @@ func TestCreateDelegates(t *testing.T) {
 	// function code.  For this test, it is a name derived from the test path.
 	// An example image name is returned.
 	builder.BuildFn = func(name2, path2 string) (string, error) {
-		if name != name {
+		if name != name2 {
 			t.Fatalf("builder expected name %v, got '%v'", name, name2)
 		}
 		expectedPath, err := filepath.Abs(root)
@@ -242,11 +250,17 @@ func TestCreateLocal(t *testing.T) {
 	)
 
 	// Create the test function root
-	os.MkdirAll(root, 0700)
+	err := os.MkdirAll(root, 0700)
+	if err != nil {
+		panic(err)
+	}
 	defer os.RemoveAll(root)
 
 	// Create the test function root
-	os.MkdirAll(root, 0700)
+	err = os.MkdirAll(root, 0700)
+	if err != nil {
+		panic(err)
+	}
 	defer os.RemoveAll(root)
 
 	client, err := faas.New(
@@ -288,7 +302,10 @@ func TestCreateInternal(t *testing.T) {
 func TestCreateDomain(t *testing.T) {
 	// Create the test function root
 	root := "testdata/example.com/admin"
-	os.MkdirAll(root, 0700)
+	err := os.MkdirAll(root, 0700)
+	if err != nil {
+		panic(err)
+	}
 	defer os.RemoveAll(root)
 
 	// the mock dns provider does nothing but receive the caluclated
@@ -321,7 +338,10 @@ func TestCreateDomain(t *testing.T) {
 func TestCreateSubdomain(t *testing.T) {
 	// Create the test function root
 	root := "testdata/example.com/admin"
-	os.MkdirAll(root, 0700)
+	err := os.MkdirAll(root, 0700)
+	if err != nil {
+		panic(err)
+	}
 	defer os.RemoveAll(root)
 
 	dnsProvider := mock.NewDNSProvider()
@@ -397,7 +417,7 @@ func TestUpdate(t *testing.T) {
 	// function code.  For this test, it is a name derived from the test path.
 	// An example image name is returned.
 	builder.BuildFn = func(name2, path2 string) (string, error) {
-		if name != name {
+		if name != name2 {
 			t.Fatalf("builder expected name %v, got '%v'", name, name2)
 		}
 		// The final image name will be determined by the builder implementation,
@@ -485,12 +505,15 @@ func TestRemoveUninitializedFails(t *testing.T) {
 		root    = "testdata/example.com/admin"
 		remover = mock.NewRemover()
 	)
-	os.MkdirAll(root, 0700)
+	err := os.MkdirAll(root, 0700)
+	if err != nil {
+		panic(err)
+	}
 	defer os.RemoveAll(root)
 
 	// Create a remover delegate which fails if invoked.
 	remover.RemoveFn = func(name string) error {
-		return errors.New(fmt.Sprintf("remove invoked for unitialized function %v", name))
+		return fmt.Errorf("remove invoked for unitialized function %v", name)
 	}
 
 	// Instantiate the client with the failing remover.
@@ -549,7 +572,10 @@ func TestWithName(t *testing.T) {
 	// Path which would derive to service.groupA.example.com were it not for the
 	// explicitly provided name.
 	path := "testdata/example.com/groupA/service"
-	os.MkdirAll(path, 0700)
+	err := os.MkdirAll(path, 0700)
+	if err != nil {
+		panic(err)
+	}
 	defer os.RemoveAll(path)
 
 	initializer := mock.NewInitializer()

cmd/completion.go

@@ -35,8 +35,8 @@ source <(faas completion bash)
 			return errors.New("missing argument")
 		}
 		if args[0] == "bash" {
-			root.GenBashCompletion(os.Stdout)
+			err = root.GenBashCompletion(os.Stdout)
-			return nil
+			return err
 		}
 		if args[0] == "zsh" {
 			// manually edited script based on `root.GenZshCompletion(os.Stdout)`

cmd/completion_util.go

@@ -29,7 +29,7 @@ func CompleteFunctionList(cmd *cobra.Command, args []string, toComplete string)
 }
 func CompleteRuntimeList(cmd *cobra.Command, args []string, toComplete string) (strings []string, directive cobra.ShellCompDirective) {
 	strings = make([]string, 0, len(appsody.StackShortNames))
-	for lang, _ := range appsody.StackShortNames {
+	for lang := range appsody.StackShortNames {
 		strings = append(strings, lang)
 	}
 	directive = cobra.ShellCompDirectiveDefault
@@ -62,7 +62,7 @@ func CompleteRegistryList(cmd *cobra.Command, args []string, toComplete string)
 		return
 	}
 	strings = make([]string, len(auth))
-	for reg, _ := range auth {
+	for reg := range auth {
 		strings = append(strings, reg)
 	}
 	directive = cobra.ShellCompDirectiveDefault

cmd/create.go

@@ -3,13 +3,11 @@ package cmd
 import (
 	"errors"
 	"fmt"
-	"os"
-	"path/filepath"
-	"regexp"
-
 	"github.com/mitchellh/go-homedir"
 	"github.com/ory/viper"
 	"github.com/spf13/cobra"
+	"os"
+	"path/filepath"
 
 	"github.com/boson-project/faas"
 	"github.com/boson-project/faas/buildpacks"
@@ -30,7 +28,10 @@ func init() {
 	createCmd.Flags().StringP("namespace", "s", "", "namespace at image registry (usually username or org name). $FAAS_NAMESPACE")
 	createCmd.Flags().StringP("template", "t", embedded.DefaultTemplate, "Function template (ex: 'http','events'). $FAAS_TEMPLATE")
 	createCmd.Flags().StringP("templates", "", filepath.Join(configPath(), "faas", "templates"), "Extensible templates path. $FAAS_TEMPLATES")
-	createCmd.RegisterFlagCompletionFunc("registry", CompleteRegistryList)
+	err := createCmd.RegisterFlagCompletionFunc("registry", CompleteRegistryList)
+	if err != nil {
+		fmt.Println("Error while calling RegisterFlagCompletionFunc: ", err)
+	}
 }
 
 // The create command invokes the Funciton Client to create a new,
@@ -44,13 +45,13 @@ var createCmd = &cobra.Command{
 	Args:              cobra.ExactArgs(1),
 	RunE:              create,
 	PreRun: func(cmd *cobra.Command, args []string) {
-		viper.BindPFlag("local", cmd.Flags().Lookup("local"))
+		flags := []string{"local", "internal", "name", "registry", "namespace", "template", "templates"}
-		viper.BindPFlag("internal", cmd.Flags().Lookup("internal"))
+		for _, f := range flags {
-		viper.BindPFlag("name", cmd.Flags().Lookup("name"))
+			err := viper.BindPFlag(f, cmd.Flags().Lookup(f))
-		viper.BindPFlag("registry", cmd.Flags().Lookup("registry"))
+			if err != nil {
-		viper.BindPFlag("namespace", cmd.Flags().Lookup("namespace"))
+				panic(err)
-		viper.BindPFlag("template", cmd.Flags().Lookup("template"))
+			}
-		viper.BindPFlag("templates", cmd.Flags().Lookup("templates"))
+		}
 	},
 }
 
@@ -224,13 +225,6 @@ func promptForName(label string, config createConfig) (string, error) {
 	return prompt.ForString("Name of service function", config.Name, prompt.WithRequired(true)), nil
 }
 
-// acceptable answers: y,yes,Y,YES,1
-var confirmExp = regexp.MustCompile("(?i)y(?:es)?|1")
-
-func fromYN(s string) bool {
-	return confirmExp.MatchString(s)
-}
-
 func configPath() (path string) {
 	if path = os.Getenv("XDG_CONFIG_HOME"); path != "" {
 		return

cmd/delete.go

@@ -1,6 +1,7 @@
 package cmd
 
 import (
+	"fmt"
 	"github.com/boson-project/faas"
 	"github.com/boson-project/faas/knative"
 	"github.com/ory/viper"
@@ -10,7 +11,10 @@ import (
 func init() {
 	root.AddCommand(deleteCmd)
 	deleteCmd.Flags().StringP("name", "n", "", "optionally specify an explicit name to remove, overriding path-derivation. $FAAS_NAME")
-	deleteCmd.RegisterFlagCompletionFunc("name", CompleteFunctionList)
+	err := deleteCmd.RegisterFlagCompletionFunc("name", CompleteFunctionList)
+	if err != nil {
+		fmt.Println("Error while calling RegisterFlagCompletionFunc: ", err)
+	}
 }
 
 var deleteCmd = &cobra.Command{
@@ -20,7 +24,10 @@ var deleteCmd = &cobra.Command{
 	SuggestFor: []string{"remove", "rm"},
 	RunE:       delete,
 	PreRun: func(cmd *cobra.Command, args []string) {
-		viper.BindPFlag("name", cmd.Flags().Lookup("name"))
+		err := viper.BindPFlag("name", cmd.Flags().Lookup("name"))
+		if err != nil {
+			panic(err)
+		}
 	},
 }
 

cmd/describe.go

@@ -21,9 +21,15 @@ func init() {
 
 	describeCmd.Flags().StringP("name", "n", "", "optionally specify an explicit name for the serive, overriding path-derivation. $FAAS_NAME")
 
-	describeCmd.RegisterFlagCompletionFunc("name", CompleteFunctionList)
+	err := describeCmd.RegisterFlagCompletionFunc("name", CompleteFunctionList)
+	if err != nil {
+		fmt.Println("Error while calling RegisterFlagCompletionFunc: ", err)
+	}
 
-	describeCmd.RegisterFlagCompletionFunc("output", CompleteOutputFormatList)
+	err = describeCmd.RegisterFlagCompletionFunc("output", CompleteOutputFormatList)
+	if err != nil {
+		fmt.Println("Error while calling RegisterFlagCompletionFunc: ", err)
+	}
 }
 
 var describeCmd = &cobra.Command{
@@ -35,8 +41,14 @@ var describeCmd = &cobra.Command{
 	Args:              cobra.ExactArgs(1),
 	RunE:              describe,
 	PreRun: func(cmd *cobra.Command, args []string) {
-		viper.BindPFlag("output", cmd.Flags().Lookup("output"))
+		err := viper.BindPFlag("output", cmd.Flags().Lookup("output"))
-		viper.BindPFlag("name", cmd.Flags().Lookup("name"))
+		if err != nil {
+			panic(err)
+		}
+		err = viper.BindPFlag("name", cmd.Flags().Lookup("name"))
+		if err != nil {
+			panic(err)
+		}
 	},
 }
 

cmd/root.go

@@ -40,7 +40,10 @@ func init() {
 	// which thus overrides both the default and the value read in from the
 	// config file (i.e. flags always take highest precidence).
 	root.PersistentFlags().BoolVarP(&verbose, "verbose", "v", verbose, "print verbose logs")
-	viper.BindPFlag("verbose", root.PersistentFlags().Lookup("verbose"))
+	err := viper.BindPFlag("verbose", root.PersistentFlags().Lookup("verbose"))
+	if err != nil {
+		panic(err)
+	}
 
 	// Override the --version template to match the output format from the
 	// version subcommand: nothing but the version.

cmd/update.go

@@ -17,7 +17,10 @@ func init() {
 	root.AddCommand(updateCmd)
 	updateCmd.Flags().StringP("registry", "r", "quay.io", "image registry (ex: quay.io). $FAAS_REGISTRY")
 	updateCmd.Flags().StringP("namespace", "s", "", "namespace at image registry (usually username or org name). $FAAS_NAMESPACE")
-	updateCmd.RegisterFlagCompletionFunc("registry", CompleteRegistryList)
+	err := updateCmd.RegisterFlagCompletionFunc("registry", CompleteRegistryList)
+	if err != nil {
+		fmt.Println("Error while calling RegisterFlagCompletionFunc: ", err)
+	}
 }
 
 var updateCmd = &cobra.Command{
@@ -27,8 +30,14 @@ var updateCmd = &cobra.Command{
 	SuggestFor: []string{"push", "deploy"},
 	RunE:       update,
 	PreRun: func(cmd *cobra.Command, args []string) {
-		viper.BindPFlag("registry", cmd.Flags().Lookup("registry"))
+		err := viper.BindPFlag("registry", cmd.Flags().Lookup("registry"))
-		viper.BindPFlag("namespace", cmd.Flags().Lookup("namespace"))
+		if err != nil {
+			panic(err)
+		}
+		err = viper.BindPFlag("namespace", cmd.Flags().Lookup("namespace"))
+		if err != nil {
+			panic(err)
+		}
 	},
 }
 

docker/pusher.go

@@ -47,7 +47,7 @@ func (n *Pusher) Push(image string) (err error) {
 	err = cmd.Run()
 	if err != nil {
 		// TODO: sanitize stderr from appsody, or submit a PR to remove duplicates etc.
-		err = errors.New(fmt.Sprintf("%v. %v", string(stderr.Bytes()), err.Error()))
+		err = fmt.Errorf("%v. %v", stderr.String(), err.Error())
 	}
 	return
 }

embedded/initializer.go

@@ -39,7 +39,7 @@ type file interface {
 // a pkger FileAccessor.
 // Path is relative to the go module root.
 func init() {
-	pkger.Include("/templates")
+	_ = pkger.Include("/templates")
 }
 
 type Initializer struct {
@@ -68,7 +68,7 @@ func (n *Initializer) Initialize(runtime, template string, dest string) error {
 	if n.templates != "" {
 		return copyFilesystem(n.templates, runtime, template, dest)
 	}
-	return errors.New(fmt.Sprintf("A template for runtime '%v' template '%v' was not found internally and no extended repository path was defined.", runtime, template))
+	return fmt.Errorf("A template for runtime '%v' template '%v' was not found internally and no extended repository path was defined.", runtime, template)
 }
 
 func copyEmbedded(runtime, template, dest string) error {

embedded/initializer_test.go

@@ -14,10 +14,13 @@ func TestInitialize(t *testing.T) {
 		testFile = "handle.go"
 		template = "http"
 	)
-	os.MkdirAll(path, 0744)
+	err := os.MkdirAll(path, 0744)
+	if err != nil {
+		panic(err)
+	}
 	defer os.RemoveAll(path)
 
-	err := NewInitializer("").Initialize("go", template, path)
+	err = NewInitializer("").Initialize("go", template, path)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -35,10 +38,13 @@ func TestDefaultTemplate(t *testing.T) {
 		testFile = "handle.go"
 		template = ""
 	)
-	os.MkdirAll(path, 0744)
+	err := os.MkdirAll(path, 0744)
+	if err != nil {
+		panic(err)
+	}
 	defer os.RemoveAll(path)
 
-	err := NewInitializer("").Initialize("go", template, path)
+	err = NewInitializer("").Initialize("go", template, path)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -64,11 +70,14 @@ func TestCustom(t *testing.T) {
 		template = "boson-experimental/json"
 		// repos    = "testdata/templates"
 	)
-	os.MkdirAll(path, 0744)
+	err := os.MkdirAll(path, 0744)
+	if err != nil {
+		panic(err)
+	}
 	defer os.RemoveAll(path)
 
 	// Unrecognized runtime/template should error
-	err := NewInitializer("").Initialize("go", template, path)
+	err = NewInitializer("").Initialize("go", template, path)
 	if err == nil {
 		t.Fatal("An unrecognized runtime/template should generate an error")
 	}
@@ -91,7 +100,10 @@ func TestCustom(t *testing.T) {
 // written with the same mode from whence they came
 func TestEmbeddedFileMode(t *testing.T) {
 	var path = "testdata/example.com/www"
-	os.MkdirAll(path, 0744)
+	err := os.MkdirAll(path, 0744)
+	if err != nil {
+		panic(err)
+	}
 	defer os.RemoveAll(path)
 
 	// Initialize a quarkus app from the embedded templates.
@@ -119,11 +131,14 @@ func TestFileMode(t *testing.T) {
 		path     = "testdata/example.com/www"
 		template = "boson-experimental/http"
 	)
-	os.MkdirAll(path, 0744)
+	err := os.MkdirAll(path, 0744)
+	if err != nil {
+		panic(err)
+	}
 	defer os.RemoveAll(path)
 
 	// Initialize a quarkus app from the custom repo in ./testdata
-	if err := NewInitializer("testdata/templates").Initialize("quarkus", template, path); err != nil {
+	if err = NewInitializer("testdata/templates").Initialize("quarkus", template, path); err != nil {
 		t.Fatal(err)
 	}
 

function.go

@@ -15,8 +15,6 @@ type Function struct {
 	root    string
 	runtime string // will be empty unless initialized/until initialized
 	name    string // will be empty unless initialized/until initialized.
-
-	initializer Initializer
 }
 
 func NewFunction(root string) (f *Function, err error) {
@@ -55,7 +53,7 @@ func (f *Function) Initialize(runtime, context, name string, domainSearchLimit i
 	if err != nil {
 		return
 	} else if len(files) > 0 {
-		return errors.New(fmt.Sprintf("The chosen directory '%v' contains contentious files: %v.  Has the Service Function already been created?  Try either using a different directory, deleting the service function if it exists, or manually removing the files.", f.root, files))
+		return fmt.Errorf("The chosen directory '%v' contains contentious files: %v.  Has the Service Function already been created?  Try either using a different directory, deleting the service function if it exists, or manually removing the files.", f.root, files)
 	}
 
 	// Ensure there are no non-hidden files, and again none of the aforementioned contentious files.

function_unit_test.go

@@ -1,6 +1,7 @@
 package faas
 
 import (
+	"fmt"
 	"io/ioutil"
 	"os"
 	"path/filepath"
@@ -85,7 +86,11 @@ func TestApplyConfig(t *testing.T) {
 	// Create a temporary directory
 	root := "./testdata/example.com/cfgtest"
 	cfgFile := filepath.Join(root, ConfigFileName)
-	os.MkdirAll(root, 0700)
+	err := os.MkdirAll(root, 0700)
+	if err != nil {
+		fmt.Println("Error on TestApplyConfig: ", err)
+		return
+	}
 	defer os.RemoveAll(root)
 
 	c := Function{name: "staticDefault"}

kn/updater.go

@@ -57,7 +57,7 @@ func (d *Updater) Update(name, image string) (err error) {
 	// Run the command, echoing captured stderr as well ass the cmd internal error.
 	if err = cmd.Run(); err != nil {
 		// TODO: sanitize stderr from appsody, or submit a PR to remove duplicates etc.
-		return errors.New(fmt.Sprintf("%v. %v", string(stderr.Bytes()), err.Error()))
+		return fmt.Errorf("%v. %v", stderr.String(), err.Error())
 	}
 
 	// TODO: explicitly pull address:

knative/deployer.go

@@ -2,7 +2,6 @@ package knative
 
 import (
 	"bytes"
-	"errors"
 	"fmt"
 	"github.com/boson-project/faas"
 	"github.com/boson-project/faas/k8s"
@@ -30,13 +29,14 @@ func (deployer *Deployer) Deploy(name, image string) (address string, err error)
 	}
 	nn := strings.Split(name, ".")
 	if len(nn) < 3 {
-		err = errors.New(fmt.Sprintf("invalid service name '%v', must be at least three parts.\n", name))
+		err = fmt.Errorf("invalid service name '%v', must be at least three parts.\n", name)
+		return
 	}
 
 	subDomain := nn[0]
 	domain := strings.Join(nn[1:], ".")
 
-	output := io.Writer(nil)
+	var output io.Writer
 	if deployer.Verbose {
 		output = os.Stdout
 	} else {

knative/remover.go

@@ -27,7 +27,7 @@ func (remover *Remover) Remove(name string) (err error) {
 		return
 	}
 
-	output := io.Writer(nil)
+	var output io.Writer
 	if remover.Verbose {
 		output = os.Stdout
 	} else {

kubectl/deployer.go

@@ -85,7 +85,7 @@ func (d *Deployer) Deploy(name, image string) (address string, err error) {
 
 	nn := strings.Split(name, ".")
 	if len(nn) < 3 {
-		err = errors.New(fmt.Sprintf("invalid service name '%v', must be at least three parts.\n", name))
+		err = fmt.Errorf("invalid service name '%v', must be at least three parts.\n", name)
 	}
 	subdomain := nn[0]
 	domain := strings.Join(nn[1:], ".")
@@ -122,7 +122,7 @@ func (d *Deployer) Deploy(name, image string) (address string, err error) {
 	err = cmd.Run()
 	if err != nil {
 		// TODO: sanitize stderr from appsody, or submit a PR to remove duplicates etc.
-		err = errors.New(fmt.Sprintf("%v. %v", string(stderr.Bytes()), err.Error()))
+		err = fmt.Errorf("%v. %v", stderr.String(), err.Error())
 		return
 	}
 

kubectl/remover.go

@@ -54,7 +54,7 @@ func (d *Remover) Remove(name string) (err error) {
 	// Run the command, echoing captured stderr as well as the cmd internal error.
 	err = cmd.Run()
 	if err != nil {
-		err = errors.New(fmt.Sprintf("%v. %v", string(stderr.Bytes()), err.Error()))
+		err = fmt.Errorf("%v. %v", stderr.String(), err.Error())
 	}
 	return
 }

mock/initializer.go

@@ -1,7 +1,6 @@
 package mock
 
 import (
-	"errors"
 	"fmt"
 	"strings"
 )
@@ -22,7 +21,7 @@ func NewInitializer() *Initializer {
 func (i *Initializer) Initialize(runtime, template, path string) error {
 	i.InitializeInvoked = true
 	if !i.supportsRuntime(runtime) {
-		return errors.New(fmt.Sprintf("unsupported runtime '%v'", runtime))
+		return fmt.Errorf("unsupported runtime '%v'", runtime)
 	}
 	return i.InitializeFn(runtime, template, path)
 }

progress/progress.go

@@ -196,7 +196,7 @@ func (b *Bar) overwrite(prefix string) {
 func (b *Bar) spin(ch <-chan time.Time) {
 	spinner := []string{"|", "/", "-", "\\"}
 	idx := 0
-	for _ = range ch {
+	for range ch {
 		// Writes the spinner frame at the beginning of the previous line, moving
 		// the cursor back to the beginning of the current line for any errors or
 		// informative messages.

prompt/prompt.go

@@ -98,14 +98,23 @@ func ForString(label string, dflt string, options ...Option) string {
 }
 
 func writeStringLabel(p *stringPrompt) {
-	p.out.Write([]byte(p.label))
+	_, err := p.out.Write([]byte(p.label))
+	if err != nil {
+		panic(err)
+	}
 	if p.dflt != "" {
 		if p.label != "" {
-			p.out.Write([]byte(" "))
+			_, err = p.out.Write([]byte(" "))
+			if err != nil {
+				panic(err)
+			}
 		}
 		fmt.Fprintf(p.out, "(%v)", p.dflt)
 	}
-	p.out.Write([]byte(p.delim))
+	_, err = p.out.Write([]byte(p.delim))
+	if err != nil {
+		panic(err)
+	}
 }
 
 func readString(p *stringPrompt) (s string, err error) {
@@ -151,16 +160,25 @@ func ForBool(label string, dflt bool, options ...Option) bool {
 }
 
 func writeBoolLabel(p *boolPrompt) {
-	p.out.Write([]byte(p.label))
+	_, err := p.out.Write([]byte(p.label))
-	if p.label != "" {
+	if err != nil {
-		p.out.Write([]byte(" "))
+		panic(err)
 	}
-	if p.dflt == true {
+	if p.label != "" {
+		_, err = p.out.Write([]byte(" "))
+		if err != nil {
+			panic(err)
+		}
+	}
+	if p.dflt {
 		fmt.Fprint(p.out, "(Y/n)")
 	} else {
 		fmt.Fprint(p.out, "(y/N)")
 	}
-	p.out.Write([]byte(p.delim))
+	_, err = p.out.Write([]byte(p.delim))
+	if err != nil {
+		panic(err)
+	}
 }
 
 func readBool(p *boolPrompt) (bool, error) {
@@ -194,6 +212,9 @@ func isFalsy(confirm string) bool {
 }
 
 func writeError(err error, p *prompt) {
-	p.out.Write([]byte("\n"))
+	_, _err := p.out.Write([]byte("\n"))
+	if _err != nil {
+		panic(_err)
+	}
 	fmt.Fprintln(p.out, err)
 }

prompt/prompt_test.go

@@ -18,8 +18,8 @@ func TestForStringLabel(t *testing.T) {
 	// Empty label
 	_ = prompt.ForString("", "",
 		prompt.WithInput(&in), prompt.WithOutput(&out))
-	if string(out.Bytes()) != ": " {
+	if out.String() != ": " {
-		t.Fatalf("expected output to be ': ', got '%v'\n", string(out.Bytes()))
+		t.Fatalf("expected output to be ': ', got '%v'\n", out.String())
 	}
 
 	out.Reset()
@@ -30,8 +30,8 @@ func TestForStringLabel(t *testing.T) {
 	// Populated lable
 	_ = prompt.ForString("Name", "",
 		prompt.WithInput(&in), prompt.WithOutput(&out))
-	if string(out.Bytes()) != "Name: " {
+	if out.String() != "Name: " {
-		t.Fatalf("expected 'Name', got '%v'\n", string(out.Bytes()))
+		t.Fatalf("expected 'Name', got '%v'\n", out.String())
 	}
 }
 
@@ -45,8 +45,8 @@ func TestForStringLabelDefault(t *testing.T) {
 	// No lablel but a default
 	_ = prompt.ForString("", "Alice",
 		prompt.WithInput(&in), prompt.WithOutput(&out))
-	if string(out.Bytes()) != "(Alice): " {
+	if out.String() != "(Alice): " {
-		t.Fatalf("expected '(Alice): ', got '%v'\n", string(out.Bytes()))
+		t.Fatalf("expected '(Alice): ', got '%v'\n", out.String())
 	}
 
 	out.Reset()
@@ -56,8 +56,8 @@ func TestForStringLabelDefault(t *testing.T) {
 	// Label with default
 	_ = prompt.ForString("Name", "Alice",
 		prompt.WithInput(&in), prompt.WithOutput(&out))
-	if string(out.Bytes()) != "Name (Alice): " {
+	if out.String()!= "Name (Alice): " {
-		t.Fatalf("expected 'Name (Alice): ', got '%v'\n", string(out.Bytes()))
+		t.Fatalf("expected 'Name (Alice): ', got '%v'\n", out.String())
 	}
 }
 
@@ -71,8 +71,8 @@ func TestWithDelimiter(t *testing.T) {
 		prompt.WithInput(&in),
 		prompt.WithOutput(&out),
 		prompt.WithDelimiter("Δ"))
-	if string(out.Bytes()) != "Δ" {
+	if out.String() != "Δ" {
-		t.Fatalf("expected output to be 'Δ', got '%v'\n", string(out.Bytes()))
+		t.Fatalf("expected output to be 'Δ', got '%v'\n", out.String())
 	}
 }
 
@@ -119,7 +119,7 @@ func TestForStringRequired(t *testing.T) {
 		prompt.WithRequired(true),
 		prompt.WithRetryLimit(1)) // makes the output buffer easier to confirm
 
-	output := string(out.Bytes())
+	output := out.String()
 	expected := ": \nplease enter a value\n: "
 	if output != expected {
 		t.Fatalf("Unexpected prompt received for a required value. expected '%v', got '%v'", expected, output)
@@ -150,8 +150,8 @@ func TestForBoolLabel(t *testing.T) {
 	// Empty label, default false
 	_ = prompt.ForBool("", false,
 		prompt.WithInput(&in), prompt.WithOutput(&out))
-	if string(out.Bytes()) != "(y/N): " {
+	if out.String() != "(y/N): " {
-		t.Fatalf("expected output to be '(y/N): ', got '%v'\n", string(out.Bytes()))
+		t.Fatalf("expected output to be '(y/N): ', got '%v'\n", out.String())
 	}
 
 	out.Reset()
@@ -162,8 +162,8 @@ func TestForBoolLabel(t *testing.T) {
 	// Empty label, default true
 	_ = prompt.ForBool("", true,
 		prompt.WithInput(&in), prompt.WithOutput(&out))
-	if string(out.Bytes()) != "(Y/n): " {
+	if out.String() != "(Y/n): " {
-		t.Fatalf("expected output to be '(Y/n): ', got '%v'\n", string(out.Bytes()))
+		t.Fatalf("expected output to be '(Y/n): ', got '%v'\n", out.String())
 	}
 
 	out.Reset()
@@ -174,8 +174,8 @@ func TestForBoolLabel(t *testing.T) {
 	// Populated lablel default false
 	_ = prompt.ForBool("Local", false,
 		prompt.WithInput(&in), prompt.WithOutput(&out))
-	if string(out.Bytes()) != "Local (y/N): " {
+	if out.String() != "Local (y/N): " {
-		t.Fatalf("expected 'Local (y/N): ', got '%v'\n", string(out.Bytes()))
+		t.Fatalf("expected 'Local (y/N): ', got '%v'\n", out.String())
 	}
 }