feat: Add Init command - create configuration file

cmd/commands/init.go

@@ -0,0 +1,61 @@
+package commands
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"os"
+
+	"github.com/thumbrise/commitlint-scope/pkg/validator"
+	"github.com/urfave/cli/v3"
+)
+
+var (
+	ErrFileExists = errors.New("file already exists")
+	ErrOpen       = errors.New("cannot open file")
+	ErrWrite      = errors.New("cannot write content")
+)
+
+const InitConfigData = `#$schema: https://github.com/thumbrise/commitlint-scope/blob/main/docs/schema/config.json
+
+# Scope parsing customization. Not required, if you follow common conventional header. In example: 'type!(scope): subject'
+#scopeRegex: ^[a-z]+(?:\((?P<scope>[^)]+)\))?!?:\s
+patterns:
+  "auth": [ "services/auth/**" ]
+  "migrations": [ "database/migrations/*.sql" ]
+  "frontend": [ "**/assets/**", "**/frontend/**" ]
+  "docs": [ "**/*.md" ]
+`
+
+const (
+	InitConfigFileName = validator.ConfigName + ".yml"
+	InitConfigFileMode = 0o600
+)
+
+var InitCMD = &cli.Command{
+	Name:  "init",
+	Usage: "Initialize a config file",
+	Action: func(ctx context.Context, cmd *cli.Command) error {
+		f, err := os.OpenFile(InitConfigFileName, os.O_WRONLY|os.O_CREATE|os.O_EXCL, InitConfigFileMode)
+		if err != nil {
+			if errors.Is(err, os.ErrExist) {
+				return fmt.Errorf("%w: %s", ErrFileExists, InitConfigFileName)
+			}
+
+			return fmt.Errorf("%w: %w", ErrOpen, err)
+		}
+
+		defer func() {
+			if closeErr := f.Close(); closeErr != nil && err == nil {
+				_, _ = fmt.Fprintf(cmd.ErrWriter, "%s: %s", ErrWrite, closeErr)
+			}
+		}()
+
+		_, err = f.WriteString(InitConfigData)
+		if err != nil {
+			return fmt.Errorf("%w: %w", ErrWrite, err)
+		}
+
+		return nil
+	},
+}

cmd/root.go

@@ -16,6 +16,7 @@ var Root = &cli.Command{
 	Description: `commitlint-scope - a linter that checks if declared commit scopes match the changed files`,
 	Commands: []*cli.Command{
 		commands.RunCMD,
+		commands.InitCMD,
 	},
 	Suggest: true,
 	ExitErrHandler: func(ctx context.Context, command *cli.Command, err error) {

pkg/validator/config.go

@@ -10,7 +10,7 @@ import (
 	"github.com/spf13/viper"
 )
 
-const configName = ".commitlint-scope"
+const ConfigName = ".commitlint-scope"
 
 type Config struct {
 	ScopeRegex *regexp.Regexp      `mapstructure:"scopeRegex"`
@@ -21,7 +21,7 @@ var ErrConfigRead = errors.New("error reading config")
 
 func LoadConfig() (Config, error) {
 	v := viper.New()
-	v.SetConfigName(configName)
+	v.SetConfigName(ConfigName)
 	v.AddConfigPath(".")
 	v.SetDefault("scopeRegex", regexp.MustCompile(`^[a-z]+(?:\((?P<scope>[^)]+)\))?!?:\s`))