🆕 Add validator

Gopkg.toml

@@ -17,3 +17,7 @@
 [[constraint]]
   name = "github.com/mitchellh/go-homedir"
   version = "1.0.0"
+
+[[constraint]]
+  name = "gopkg.in/go-playground/validator.v9"
+  version = "9.21.0"

command.go

@@ -8,25 +8,17 @@ import (
 )
 
 type ArgsGetSummaries struct {
-	table string
-}
-
-func (r *ArgsGetSummaries) validate() error {
-	if r.table == "" {
-		return errors.New("Table is required")
-	}
-
-	return nil
+	Table string `validate:"required"`
 }
 
 // CmdGetSummaries show summaries
-func CmdGetSummaries(args ArgsGetSummaries) error {
+func CmdGetSummaries(args *ArgsGetSummaries) error {
 	dao, err := NewAwsDao("ap-northeast-1")
 	if err != nil {
 		return errors.Wrap(err, "Fail to create aws client.")
 	}
 
-	summaries, err := dao.FetchSummaries(args.table)
+	summaries, err := dao.FetchSummaries(args.Table)
 	if err != nil {
 		return errors.Wrap(err, "Fail to fetch summaries.")
 	}
@@ -43,30 +35,19 @@ func CmdGetSummaries(args ArgsGetSummaries) error {
 }
 
 type ArgsGetReport struct {
-	bucket       string
-	bucketPrefix string
-	key          string
-}
-
-func (r *ArgsGetReport) validate() error {
-	if r.bucket == "" {
-		return errors.New("Bucket is required")
-	}
-	if r.key == "" {
-		return errors.New("Key is required")
-	}
-
-	return nil
+	Bucket       string `validate:"required"`
+	BucketPrefix string
+	Key          string `validate:"required"`
 }
 
 // CmdGetReport show report
-func CmdGetReport(args ArgsGetReport) error {
+func CmdGetReport(args *ArgsGetReport) error {
 	dao, err := NewAwsDao("ap-northeast-1")
 	if err != nil {
 		return errors.Wrap(err, "Fail to create aws client.")
 	}
 
-	report, err := dao.FetchReport(args.bucket, args.bucketPrefix, args.key)
+	report, err := dao.FetchReport(args.Bucket, args.BucketPrefix, args.Key)
 	if err != nil {
 		return errors.Wrap(err, "Fail to fetch report.")
 	}

main.go

@@ -5,24 +5,29 @@ import (
 	"os"
 
 	"github.com/pkg/errors"
+	"gopkg.in/go-playground/validator.v9"
 )
 
-func createArgsGetSummaries(args Args, config Config) ArgsGetSummaries {
+var validate *validator.Validate
+
+func createArgsGetSummaries(args Args, config Config) *ArgsGetSummaries {
 	table := config.Table
 	if args.Table != "" {
 		table = args.Table
 	}
-	r := ArgsGetSummaries{
-		table: table,
+	r := &ArgsGetSummaries{
+		Table: table,
 	}
-	if err := r.validate(); err != nil {
+
+	err := validate.Struct(r)
+	if err != nil {
 		log.Fatal(err)
 	}
 
 	return r
 }
 
-func createArgsGetReport(args Args, config Config) ArgsGetReport {
+func createArgsGetReport(args Args, config Config) *ArgsGetReport {
 	bucket := config.Bucket
 	if args.Bucket != "" {
 		bucket = args.Bucket
@@ -31,19 +36,22 @@ func createArgsGetReport(args Args, config Config) ArgsGetReport {
 	if args.BucketPrefix != "" {
 		bucketPrefix = args.BucketPrefix
 	}
-	r := ArgsGetReport{
-		bucket:       bucket,
-		bucketPrefix: bucketPrefix,
-		key:          args.Key,
+	r := &ArgsGetReport{
+		Bucket:       bucket,
+		BucketPrefix: bucketPrefix,
+		Key:          args.Key,
 	}
-	if err := r.validate(); err != nil {
+
+	if err := validate.Struct(r); err != nil {
 		log.Fatal(err)
 	}
 
 	return r
 }
 
 func main() {
+	validate = validator.New()
+
 	args, err := CreateArgs(usage, os.Args[1:], version)
 	if err != nil {
 		log.Fatal(errors.Wrap(err, "Fail to create arguments."))