Use gometalinter and fix linting errors (#11)

Use gometalinter and fix linting errors

cmd/enforce.go

@@ -28,24 +28,23 @@ var enforceCmd = &cobra.Command{
 	Use:   "enforce",
 	Short: "",
 	Long:  ``,
-	RunE: func(cmd *cobra.Command, args []string) error {
+	RunE: func(cmd *cobra.Command, args []string) (err error) {
 		if len(args) != 1 {
-			return fmt.Errorf("Invalid argument")
+			err = fmt.Errorf("Invalid arguments %v", args)
+
+			return err
 		}
-		err := checkDockerVersion()
+		err = checkDockerVersion()
 		if err != nil {
-			return err
+			return
 		}
 		e, err := conform.NewEnforcer(args[0])
 		if err != nil {
-			return err
+			return
 		}
 		err = e.ExecuteRule()
-		if err != nil {
-			return err
-		}
 
-		return nil
+		return
 	},
 }
 
@@ -54,25 +53,27 @@ func init() {
 	RootCmd.Flags().BoolVar(&debug, "debug", false, "Debug rendering")
 }
 
-func checkDockerVersion() error {
+func checkDockerVersion() (err error) {
 	cli, err := client.NewEnvClient()
 	if err != nil {
-		return err
+		return
 	}
 
 	serverVersion, err := cli.ServerVersion(context.Background())
 	if err != nil {
-		return err
+		return
 	}
 	minVersion, err := semver.NewVersion(minDockerVersion)
 	if err != nil {
-		return err
+		return
 	}
 	serverSemVer := semver.MustParse(serverVersion.Version)
 	i := serverSemVer.Compare(minVersion)
 	if i < 0 {
-		return fmt.Errorf("At least Docker version %s is required", minDockerVersion)
+		err = fmt.Errorf("At least Docker version %s is required", minDockerVersion)
+
+		return err
 	}
 
-	return nil
+	return
 }

cmd/root.go

@@ -29,9 +29,7 @@ const (
 )
 
 var (
-	target    string
-	imageName string
-	debug     bool
+	debug bool
 )
 
 // RootCmd represents the base command when called without any subcommands

conform.yaml

@@ -67,7 +67,8 @@ templates:
   test: |
     FROM golang:1.8.3 as test
     WORKDIR /go/src/github.com/autonomy/conform
-    RUN go get -u github.com/golang/lint/golint
+    RUN go get -u gopkg.in/alecthomas/gometalinter.v1
+    RUN gometalinter.v1 --install
     COPY --from=build /go/src/github.com/autonomy/conform .
     RUN chmod +x ./scripts/test.sh; sync; ./scripts/test.sh
   image: |

conform/enforce.go

@@ -24,29 +24,30 @@ type Enforcer struct {
 }
 
 // NewEnforcer instantiates and returns an executer.
-func NewEnforcer(rule string) (*Enforcer, error) {
-	e := &Enforcer{}
-	gitInfo := git.NewInfo()
+func NewEnforcer(rule string) (enforcer *Enforcer, err error) {
+	enforcer = &Enforcer{}
+	gitInfo, err := git.NewInfo()
+	if err != nil {
+		return
+	}
 	date := []byte{}
 	if gitInfo.IsTag {
-		_date, err := exec.Command("date").Output()
+		date, err = exec.Command("/bin/date").Output()
 		if err != nil {
-			fmt.Print(err)
+			return
 		}
-
-		date = _date
 	}
 
 	c, err := config.NewConfig()
 	if err != nil {
-		return nil, err
+		return
 	}
-	e.config = c
-	e.GitInfo = gitInfo
-	e.Built = strings.TrimSuffix(string(date), "\n")
-	e.rule = rule
+	enforcer.config = c
+	enforcer.GitInfo = gitInfo
+	enforcer.Built = strings.TrimSuffix(string(date), "\n")
+	enforcer.rule = rule
 
-	return e, nil
+	return
 }
 
 // ExecuteBuild executes a docker build.
@@ -56,19 +57,22 @@ func (e *Enforcer) ExecuteBuild() error {
 		image = e.FormatImageNameDirty()
 	}
 
-	os.Setenv("CONFORM_IMAGE", image)
+	err := os.Setenv("CONFORM_IMAGE", image)
+	if err != nil {
+		return err
+	}
 
 	args := append([]string{"build", "--tag", image, "."})
 	command := exec.Command("docker", args...)
 	command.Stdout = os.Stdout
 	command.Stderr = os.Stderr
-	command.Start()
-	err := command.Wait()
+	err = command.Start()
 	if err != nil {
 		return err
 	}
+	err = command.Wait()
 
-	return nil
+	return err
 }
 
 // RenderDockerfile writes the final Dockerfile to disk.
@@ -87,7 +91,10 @@ func (e *Enforcer) RenderDockerfile(target *config.Rule) error {
 	if e.config.Debug {
 		fmt.Println(dockerfile)
 	} else {
-		ioutil.WriteFile("Dockerfile", []byte(dockerfile), 0644)
+		err := ioutil.WriteFile("Dockerfile", []byte(dockerfile), 0644)
+		if err != nil {
+			return err
+		}
 	}
 
 	return nil
@@ -127,8 +134,11 @@ func (e *Enforcer) ExecuteScript(script string) error {
 		command := exec.Command("bash", "-c", s)
 		command.Stdout = os.Stdout
 		command.Stderr = os.Stderr
-		command.Start()
-		err := command.Wait()
+		err := command.Start()
+		if err != nil {
+			return err
+		}
+		err = command.Wait()
 		if err != nil {
 			return fmt.Errorf("Failed executing %q: %v", script, err)
 		}

conform/enforce_test.go

@@ -32,17 +32,27 @@ rules:
       - after
 `
 
+func RemoveAll(dir string) {
+	err := os.RemoveAll(dir)
+	if err != nil {
+		log.Fatal(err)
+	}
+}
+
 func TestNewEnforcer(t *testing.T) {
 	dir, err := ioutil.TempDir("", "test")
 	if err != nil {
 		log.Fatal(err)
 	}
-	defer os.RemoveAll(dir)
+	defer RemoveAll(dir)
 	tmpfn := filepath.Join(dir, "conform.yaml")
 	if err = ioutil.WriteFile(tmpfn, []byte(conformYAML), 0666); err != nil {
 		log.Fatal(err)
 	}
-	os.Chdir(dir)
+	err = os.Chdir(dir)
+	if err != nil {
+		t.Error(err)
+	}
 	output, err := exec.Command("git", "init").Output()
 	if err != nil {
 		t.Fatal(output)

conform/git/git.go

@@ -2,7 +2,6 @@ package git
 
 import (
 	"fmt"
-	"log"
 	"os"
 	"os/exec"
 	"strconv"
@@ -22,66 +21,115 @@ type Info struct {
 }
 
 // NewInfo instantiates and returns info.
-func NewInfo() *Info {
-	branch, err := exec.Command("git", "rev-parse", "--abbrev-ref", "HEAD").Output()
+func NewInfo() (info *Info, err error) {
+	branch, err := Branch()
 	if err != nil {
-		log.Fatalf("Failed to get branch [%v]", err)
+		return
 	}
-	fmt.Printf("Branch: %s\n", strings.TrimSuffix(string(branch), "\n"))
-	os.Setenv("CONFORM_BRANCH", strings.TrimSuffix(string(branch), "\n"))
 
-	sha, err := exec.Command("git", "rev-parse", "--short", "HEAD").Output()
+	sha, err := SHA()
 	if err != nil {
-		log.Fatalf("Failed to get sha [%v]", err)
+		return
 	}
-	fmt.Printf("SHA: %s\n", strings.TrimSuffix(string(sha), "\n"))
-	os.Setenv("CONFORM_SHA", strings.TrimSuffix(string(sha), "\n"))
 
-	tag := "undefined"
-	isTag := false
-	_tag, err := exec.Command("git", "describe", "--exact-match", "--tags", "HEAD").Output()
-	if err == nil {
-		isTag = true
+	tag, isTag, err := Tag()
+	if err != nil {
+		return
 	}
-	if isTag {
-		tag = string(_tag)
+
+	_, isDirty, err := Status()
+	if err != nil {
+		return
 	}
-	fmt.Printf("IsTag: %v\n", isTag)
-	os.Setenv("CONFORM_IS_TAG", strconv.FormatBool(isTag))
-	fmt.Printf("Tag: %s\n", strings.TrimSuffix(string(tag), "\n"))
-	os.Setenv("CONFORM_TAG", strings.TrimSuffix(string(tag), "\n"))
 
-	status, err := exec.Command("git", "status", "--porcelain").Output()
+	info = &Info{
+		Branch:  branch,
+		SHA:     sha,
+		Tag:     strings.TrimSuffix(tag, "\n"),
+		IsTag:   isTag,
+		IsDirty: isDirty,
+	}
+
+	return
+}
+
+// Branch returns the current git branch name.
+func Branch() (branch string, err error) {
+	branchBytes, err := exec.Command("git", "rev-parse", "--abbrev-ref", "HEAD").Output()
 	if err != nil {
-		log.Fatal(err)
+		return
 	}
-	fmt.Printf("Status: %s\n", strings.TrimSuffix(string(status), "\n"))
+	branch = strings.TrimSuffix(string(branchBytes), "\n")
+	err = ExportConformVar("branch", branch)
+	fmt.Printf("Branch: %s\n", branch)
 
-	isDirty := false
-	if strings.TrimSuffix(string(status), "\n") != "" {
-		isDirty = true
+	return
+}
+
+// SHA returns the sha of the current commit.
+func SHA() (sha string, err error) {
+	shaBytes, err := exec.Command("git", "rev-parse", "--short", "HEAD").Output()
+	if err != nil {
+		return
 	}
-	fmt.Printf("IsDirty: %v\n", isDirty)
-	os.Setenv("CONFORM_IS_DIRTY", strconv.FormatBool(isDirty))
+	sha = strings.TrimSuffix(string(shaBytes), "\n")
+	err = ExportConformVar("sha", sha)
+	fmt.Printf("SHA: %s\n", sha)
+
+	return
+}
 
-	prerelease := ""
+// Tag returns the tag name if HEAD is a tag.
+func Tag() (tag string, isTag bool, err error) {
+	tagBytes, isTagErr := exec.Command("git", "describe", "--exact-match", "--tags", "HEAD").Output()
+	if isTagErr == nil {
+		isTag = true
+	}
+	tag = strings.TrimSuffix(string(tagBytes), "\n")
 	if isTag {
-		sv, err := semver.NewVersion(strings.TrimSuffix(string(tag[1:]), "\n"))
+		_, err = semver.NewVersion(tag[1:])
 		if err != nil {
-			log.Fatal(err)
+			return
 		}
+	}
+	err = ExportConformVar("tag", tag)
+	if err != nil {
+		return
+	}
+	err = ExportConformVar("is_tag", strconv.FormatBool(isTag))
+	if err != nil {
+		return
+	}
+	fmt.Printf("IsTag: %v\n", isTag)
+	fmt.Printf("Tag: %s\n", tag)
+
+	return
+}
 
-		prerelease = sv.Prerelease()
+// Status returns the status of the working tree.
+func Status() (status string, isDirty bool, err error) {
+	statusBytes, err := exec.Command("git", "status", "--porcelain").Output()
+	if err != nil {
+		return
 	}
-	fmt.Printf("Prerelease: %s\n", prerelease)
-	os.Setenv("CONFORM_PRERELEASE", prerelease)
-
-	return &Info{
-		Branch:     strings.TrimSuffix(string(branch), "\n"),
-		SHA:        strings.TrimSuffix(string(sha), "\n"),
-		Tag:        strings.TrimSuffix(string(tag), "\n"),
-		Prerelease: prerelease,
-		IsTag:      isTag,
-		IsDirty:    isDirty,
+	status = strings.TrimSuffix(string(statusBytes), "\n")
+	if status != "" {
+		isDirty = true
 	}
+	err = ExportConformVar("is_dirty", strconv.FormatBool(isDirty))
+	if err != nil {
+		return
+	}
+	fmt.Printf("Status: %s\n", status)
+	fmt.Printf("IsDirty: %v\n", isDirty)
+
+	return
+}
+
+// ExportConformVar exports variable prefixed with CONFORM_
+func ExportConformVar(name, value string) (err error) {
+	variable := fmt.Sprintf("CONFORM_%s", strings.ToUpper(name))
+	err = os.Setenv(variable, value)
+
+	return
 }