Adding hungarian add-on

addons/hu/osa/extensions.go

@@ -10,7 +10,7 @@ const (
 	ExtKeyExemptionValue = "hu-exemption-Value"
 )
 
-var extensionKeys = []*cbc.KeyDefinition{
+var extensions = []*cbc.KeyDefinition{
 	{
 		Key: ExtKeyExemptionValue,
 		Name: i18n.String{

addons/hu/osa/osa.go

@@ -0,0 +1,28 @@
+// Package osa handles the extensions and validation rules in order to use GOBL with the
+// Hungarian OSA format.
+package osa
+
+import (
+	"github.com/invopop/gobl/cbc"
+	"github.com/invopop/gobl/i18n"
+	"github.com/invopop/gobl/tax"
+)
+
+const (
+	// V3 for Hungary OSA XML v3.x
+	V3 cbc.Key = "hu-osa-v3"
+)
+
+func init() {
+	tax.RegisterAddonDef(newAddon())
+}
+
+func newAddon() *tax.AddonDef {
+	return &tax.AddonDef{
+		Key: V3,
+		Name: i18n.String{
+			i18n.EN: "Hungary OSA v3.x",
+		},
+		Extensions: extensions,
+	}
+}