Run lint static analysis on the repository as part of CI

[YuviGold]

Expected Behaviour

Fail CI on linting errors

Current Behaviour

No static analysis validations.

Are you a GitHub Sponsor yet (Yes/No?)

• Yes
• No

Possible Solution

Use https://github.com/golangci/golangci-lint as make lint.

Context

The arkade repository is becoming bigger, and it's recommended to follow some linting rules as a standard. There are static analysis tools that can take of that.
Using a linter is a best practice and might even find some bugs.

Running golangci-lint on arkade

➜  arkade git:(master) golangci-lint run ./...
pkg/archive/untar.go:116:6: `validRelativeDir` is unused (deadcode)
func validRelativeDir(dir string) bool {
     ^
pkg/archive/unzip.go:25:15: copylocks: call of unzip copies lock value: archive/zip.Reader contains sync.Once contains sync.Mutex (govet)
	return unzip(*zipReader, dir, quiet)
	             ^
pkg/archive/unzip.go:28:14: copylocks: unzip passes lock by value: archive/zip.Reader contains sync.Once contains sync.Mutex (govet)
func unzip(r zip.Reader, dir string, quiet bool) (err error) {
             ^
cmd/apps/minio_app.go:152:8: `clientOS` is unused (deadcode)
var _, clientOS = env.GetClientArch()
       ^
cmd/apps/osm_app.go:163:5: `osmInstallMsg` is unused (deadcode)
var osmInstallMsg = `=======================================================================
    ^
pkg/get/get.go:373:10: Error return value of `t.Parse` is not checked (errcheck)
		t.Parse(`Run the following to copy to install the tool:
		       ^
pkg/get/get.go:381:10: Error return value of `t.Parse` is not checked (errcheck)
		t.Parse(`# Add arkade binary directory to your PATH variable
		       ^
cmd/apps/metallb_app.go:80:13: Error return value of `rand.Read` is not checked (errcheck)
			rand.Read(randomToken)
			         ^
cmd/apps/of_loki.go:63:14: Error return value of `k8s.Kubectl` is not checked (errcheck)
		k8s.Kubectl("-n", openfaasNamespace,
		           ^
cmd/apps/openfaas_app.go:297:12: Error return value of `pem.Encode` is not checked (errcheck)
	pem.Encode(&privOut, &pem.Block{Type: "EC PRIVATE KEY", Bytes: ecder})
	          ^
cmd/apps/openfaas_app.go:306:12: Error return value of `pem.Encode` is not checked (errcheck)
	pem.Encode(&pubOut, &pem.Block{Type: "PUBLIC KEY", Bytes: pubder})
	          ^
cmd/completion.go:57:32: Error return value of `(*github.com/spf13/cobra.Command).GenBashCompletion` is not checked (errcheck)
			cmd.Root().GenBashCompletion(os.Stdout)
			                            ^
cmd/completion.go:61:32: Error return value of `(*github.com/spf13/cobra.Command).GenFishCompletion` is not checked (errcheck)
			cmd.Root().GenFishCompletion(os.Stdout, true)
			                            ^
cmd/completion.go:63:38: Error return value of `(*github.com/spf13/cobra.Command).GenPowerShellCompletion` is not checked (errcheck)
			cmd.Root().GenPowerShellCompletion(os.Stdout)
			                                  ^
cmd/completion.go:77:31: Error return value of `(*github.com/spf13/cobra.Command).GenZshCompletion` is not checked (errcheck)
	rootCmd(cmd).GenZshCompletion(out)
	                             ^
cmd/completion.go:78:16: Error return value of `io.WriteString` is not checked (errcheck)
	io.WriteString(out, zshCompdef)
	              ^
main.go:22:12: Error return value of `cmd.Help` is not checked (errcheck)
			cmd.Help()
			        ^
cmd/apps/inletsoperator_app.go:176:9: S1002: should omit comparison to bool constant, can be simplified to `!fileFlagChanged` (gosimple)
					if fileFlagChanged == false {
					   ^
cmd/apps/openfaas_app.go:192:6: S1002: should omit comparison to bool constant, can be simplified to `!basicAuthEnabled` (gosimple)
		if basicAuthEnabled == false {
		   ^
pkg/get/download.go:63:68: S1002: should omit comparison to bool constant, can be simplified to `!tool.NoExtension` (gosimple)
	if strings.Contains(strings.ToLower(operatingSystem), "mingw") && tool.NoExtension == false {
	                                                                  ^
pkg/get/download.go:201:68: S1002: should omit comparison to bool constant, can be simplified to `!tool.NoExtension` (gosimple)
	if strings.Contains(strings.ToLower(operatingSystem), "mingw") && tool.NoExtension == false {
	                                                                  ^
cmd/apps/linkerd_app.go:169:16: S1025: the argument is already a string, there's no need to use fmt.Sprintf (gosimple)
		Command:     fmt.Sprintf("%s", env.LocalBinary("linkerd2", "")),
		             ^
cmd/apps/osm_app.go:126:16: S1025: the argument is already a string, there's no need to use fmt.Sprintf (gosimple)
		Command:     fmt.Sprintf("%s", env.LocalBinary("osm", "")),
		             ^
pkg/get/get_test.go:143:11: S1025: the argument's underlying type is a slice of bytes, should use a simple conversion instead of fmt.Sprintf (gosimple)
			got := fmt.Sprintf("%s", msg)
			       ^
pkg/helm/helm.go:93:16: S1025: the argument is already a string, there's no need to use fmt.Sprintf (gosimple)
		Command:     fmt.Sprintf("%s", env.LocalBinary("helm", subdir)),
		             ^
cmd/apps/openfaas_app.go:276:3: S1023: redundant break statement (gosimple)
		break
		^
cmd/apps/openfaas_app.go:279:3: S1023: redundant break statement (gosimple)
		break
		^
cmd/apps/minio_app.go:113:15: ineffectual assignment to err (ineffassign)
			accessKey, err = gen.Generate(20, 10, 0, false, true)
			           ^
cmd/apps/minio_app.go:117:15: ineffectual assignment to err (ineffassign)
			secretKey, err = gen.Generate(40, 10, 5, false, true)
			           ^
cmd/apps/openfaas_ingress_app.go:173:3: SA1006: printf-style function with dynamic format string and no further arguments should use print-style function instead (staticcheck)
		log.Printf(tempDirectory)
		^
cmd/apps/registry_app.go:155:4: SA1006: printf-style function with dynamic format string and no further arguments should use print-style function instead (staticcheck)
			fmt.Printf(fmt.Sprintf("Registry credentials: %s %s\nexport PASSWORD=%s\n", username, pass, pass))

Your Environment

• What Kubernetes distribution are you using?

kubectl version
Client Version: version.Info{Major:"1", Minor:"22", GitVersion:"v1.22.2", GitCommit:"8b5a19147530eaac9476b0ab82980b4088bbc1b2", GitTreeState:"clean", BuildDate:"2021-09-15T21:38:50Z", GoVersion:"go1.16.8", Compiler:"gc", Platform:"linux/amd64"}

• Operating System and version (e.g. Linux, Windows, MacOS):

uname -a

Linux yuvalgold 5.10.0-1050-oem #52-Ubuntu SMP Wed Oct 6 12:58:49 UTC 2021 x86_64 x86_64 x86_64 GNU/Linux

• What arkade version is this?

arkade version
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 / _` | '__| |/ / _` |/ _` |/ _ \
| (_| | |  |   < (_| | (_| |  __/
 \__,_|_|  |_|\_\__,_|\__,_|\___|

Open Source Marketplace For Developer Tools

Version: 0.8.42
Git Commit: cd54f6a171afb07ef27f8e8e23e9cb13a4e3878b

 🐳 arkade needs your support: https://github.com/sponsors/alexellis