refactor: openpitrix module

Signed-off-by: hongming <talonwan@yunify.com>

vendor/github.com/koding/multiconfig/validator.go

@@ -0,0 +1,73 @@
+package multiconfig
+
+import (
+	"fmt"
+	"reflect"
+
+	"github.com/fatih/structs"
+)
+
+// Validator validates the config against any predefined rules, those predefined
+// rules should be given to this package. The implementer will be responsible
+// for the logic.
+type Validator interface {
+	// Validate validates the config struct
+	Validate(s interface{}) error
+}
+
+// RequiredValidator validates the struct against zero values.
+type RequiredValidator struct {
+	//  TagName holds the validator tag name. The default is "required"
+	TagName string
+
+	// TagValue holds the expected value of the validator. The default is "true"
+	TagValue string
+}
+
+// Validate validates the given struct agaist field's zero values. If
+// intentionaly, the value of a field is `zero-valued`(e.g false, 0, "")
+// required tag should not be set for that field.
+func (e *RequiredValidator) Validate(s interface{}) error {
+	if e.TagName == "" {
+		e.TagName = "required"
+	}
+
+	if e.TagValue == "" {
+		e.TagValue = "true"
+	}
+
+	for _, field := range structs.Fields(s) {
+		if err := e.processField("", field); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+func (e *RequiredValidator) processField(fieldName string, field *structs.Field) error {
+	fieldName += field.Name()
+	switch field.Kind() {
+	case reflect.Struct:
+		// this is used for error messages below, when we have an error at the
+		// child properties add parent properties into the error message as well
+		fieldName += "."
+
+		for _, f := range field.Fields() {
+			if err := e.processField(fieldName, f); err != nil {
+				return err
+			}
+		}
+	default:
+		val := field.Tag(e.TagName)
+		if val != e.TagValue {
+			return nil
+		}
+
+		if field.IsZero() {
+			return fmt.Errorf("multiconfig: field '%s' is required", fieldName)
+		}
+	}
+
+	return nil
+}