Custom validator

README.md

@@ -190,6 +190,38 @@ type Options struct {
 }
 ```
 
+### Custom validator
+
+You can override `options-gen` validator for specific struct by implementing the `Validator()` method:
+```go
+import "github.com/mycoolmodule/internal/validator"
+
+// ...
+
+func (Options) Validator() *validator.Validate {
+  return validator.Validator
+}
+```
+
+Or you can override `options-gen` validator globally:
+```go
+package validator
+
+import (
+  goplvalidator "github.com/go-playground/validator/v10"
+  optsValidator "github.com/kazhuravlev/options-gen/pkg/validator"
+)
+
+var Validator = goplvalidator.New()
+
+func init() {
+  must(Validator.RegisterValidation(/* ... */))
+  must(Validator.RegisterAlias(/* ... */))
+
+  optsValidator.Set(Validator)
+}
+```
+
 ## Contributing
 
 The development process is pretty simple:

Taskfile.yml

@@ -85,6 +85,7 @@ tasks:
     dir: examples/library
     cmds:
       - go run main.go
+      - go test .
 
   examples:update:cli:
     dir: examples/cli

examples/library/example_in.go

@@ -13,3 +13,7 @@ type Options struct {
 type Config struct {
 	name string
 }
+
+type Params struct {
+	hash string `option:"mandatory" validate:"hexadecimal"`
+}

examples/library/main.go

@@ -5,21 +5,30 @@ import (
 )
 
 func main() {
-	if err := optionsgen.Run(
-		"./example_in.go",
-		"./example_out.go",
-		"Options",
-		"main",
-	); err != nil {
-		panic(err)
-	}
-
-	if err := optionsgen.Run(
-		"./example_in.go",
-		"./example_out_config.go",
-		"Config",
-		"main",
-	); err != nil {
-		panic(err)
+	for _, params := range []struct {
+		outFname   string
+		structName string
+	}{
+		{
+			outFname:   "./example_out_options.go",
+			structName: "Options",
+		},
+		{
+			outFname:   "./example_out_config.go",
+			structName: "Config",
+		},
+		{
+			outFname:   "./example_out_params.go",
+			structName: "Params",
+		},
+	} {
+		if err := optionsgen.Run(
+			"./example_in.go",
+			params.outFname,
+			params.structName,
+			"main",
+		); err != nil {
+			panic(err)
+		}
 	}
 }

examples/library/main_test.go

@@ -0,0 +1,9 @@
+package main
+
+import "testing"
+
+func TestMultiFile(t *testing.T) {
+	_ = NewOptions(nil, "s3")
+	_ = NewConfig()
+	_ = NewParams("d285afedd3e14589ddfe2d6bf4319bfd")
+}

internal/generator/templates/options.go.tpl

@@ -2,18 +2,14 @@
 package {{ .packageName }}
 
 import (
-    "fmt"
+    fmt461e464ebed9 "fmt"
 	errors461e464ebed9 "github.com/kazhuravlev/options-gen/pkg/errors"
-	goplvalidator "github.com/go-playground/validator/v10"
+{{ if .hasValidation }}validator461e464ebed9 "github.com/kazhuravlev/options-gen/pkg/validator"{{ end }}
 	{{- range $import := .imports }}
 	{{ $import -}}
 	{{- end }}
 )
 
-{{ if .hasValidation }}
-var _validator461e464ebed9 = goplvalidator.New()
-{{- end }}
-
 type Opt{{ $.optionsStructName }}Setter{{ $.optionsTypeParamsSpec }} func(o *{{ .optionsStructInstanceType }})
 
 func New{{ .optionsStructType }}(
@@ -45,15 +41,14 @@ func New{{ .optionsStructType }}(
 	{{ end }}
 {{ end }}
 
-
 func (o *{{ .optionsStructInstanceType }}) Validate() error {
 	{{- if not .hasValidation -}}
 		return nil
 	{{- else }}
 		errs := new(errors461e464ebed9.ValidationErrors)
 		{{- range .options }}
 			{{- if .TagOption.GoValidator }}
-				errs.Add(errors461e464ebed9.NewValidationError("{{ .Name }}", _validate_{{ $.optionsStructName }}_{{ .Field }}{{ $.optionsTypeParams }}(o)))
+				errs.Add(errors461e464ebed9.NewValidationError("{{ .Field }}", _validate_{{ $.optionsStructName }}_{{ .Field }}{{ $.optionsTypeParams }}(o)))
 			{{- end }}
 		{{- end }}
 		return errs.AsError()
@@ -63,8 +58,8 @@ func (o *{{ .optionsStructInstanceType }}) Validate() error {
 {{ range .options }}
 	{{- if .TagOption.GoValidator }}
 		func _validate_{{ $.optionsStructName }}_{{ .Field }}{{ $.optionsTypeParamsSpec }}(o *{{ $.optionsStructInstanceType }}) error {
-			if err := _validator461e464ebed9.Var(o.{{ .Field }}, "{{ .TagOption.GoValidator }}"); err != nil {
-				return fmt.Errorf("field `{{ .Field }}` did not pass the test: %w", err)
+			if err := validator461e464ebed9.GetValidatorFor(o).Var(o.{{ .Field }}, "{{ .TagOption.GoValidator }}"); err != nil {
+				return fmt461e464ebed9.Errorf("field `{{ .Field }}` did not pass the test: %w", err)
 			}
 			return nil
 		}

options-gen/custom_validator_test.go

@@ -0,0 +1,20 @@
+package optionsgen_test
+
+import (
+	"testing"
+
+	testcase "github.com/kazhuravlev/options-gen/options-gen/testdata/case-09-custom-validator"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestOptionsWithCustomValidator(t *testing.T) {
+	t.Run("valid options", func(t *testing.T) {
+		opts := testcase.NewOptions(100, 19)
+		assert.NoError(t, opts.Validate())
+	})
+
+	t.Run("invalid options", func(t *testing.T) {
+		opts := testcase.NewOptions(100, 17)
+		assert.Error(t, opts.Validate())
+	})
+}

options-gen/global_override_test.go

@@ -0,0 +1,32 @@
+package optionsgen_test
+
+import (
+	"testing"
+
+	goplvalidator "github.com/go-playground/validator/v10"
+	testcase "github.com/kazhuravlev/options-gen/options-gen/testdata/case-10-global-override"
+	"github.com/kazhuravlev/options-gen/pkg/validator"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestOptionsWithOverridenValidator(t *testing.T) {
+	v := goplvalidator.New()
+	require.NoError(t, v.RegisterValidation("child", func(fl goplvalidator.FieldLevel) bool {
+		return fl.Field().Int() < 14
+	}))
+
+	old := validator.GetValidatorFor(nil)
+	validator.Set(v)
+	t.Cleanup(func() { validator.Set(old) })
+
+	t.Run("valid options", func(t *testing.T) {
+		opts := testcase.NewOptions(100, 13)
+		assert.NoError(t, opts.Validate())
+	})
+
+	t.Run("invalid options", func(t *testing.T) {
+		opts := testcase.NewOptions(100, 14)
+		assert.Error(t, opts.Validate())
+	})
+}