update to version 0.0.2: add fallback defaultLang:key on validLang:ke…

…y not found

_examples/custom-loader/main.go

@@ -106,6 +106,7 @@ func GOI18N(globPattern string) i18n.Loader {
 			// i18n package matches the language by itself so we don't really need to do it at serve-time,
 			// this is why we preload them here.
 			locales[langIndex] = &goi18nLocale{
+				index:     langIndex,
 				id:        tag.String(),
 				tag:       &tag,
 				localizer: goI18n.NewLocalizer(b, tag.String()),
@@ -122,11 +123,16 @@ func GOI18N(globPattern string) i18n.Loader {
 }
 
 type goi18nLocale struct {
+	index     int
 	id        string
 	tag       *language.Tag
 	localizer *goI18n.Localizer
 }
 
+func (l *goi18nLocale) Index() int {
+	return l.index
+}
+
 func (l *goi18nLocale) Tag() *language.Tag {
 	return l.tag
 }

doc.go

@@ -5,7 +5,7 @@ Source code and other details for the project are available at GitHub:
 
 Current Version
 
-0.0.1
+0.0.2
 
 Installation
 

i18n.go

@@ -59,6 +59,8 @@ type (
 	// Locale is the interface which returns from a `Localizer.GetLocale` method.
 	// It serves the translations based on "key" or format. See `GetMessage`.
 	Locale interface {
+		// Index returns the current locale index from the languages list.
+		Index() int
 		// Tag returns the full language Tag attached to this Locale,
 		// it should be unique across different Locales.
 		Tag() *language.Tag
@@ -92,6 +94,9 @@ type I18n struct {
 	Cookie string
 	// If true then a subdomain can be a language identifier too.
 	Subdomain bool
+	// If true then it will return empty string when translation for a a specific language's key was not found.
+	// Defaults to false, fallback defaultLang:key will be used.
+	Strict bool
 }
 
 // makeTags converts language codes to language Tags.
@@ -291,7 +296,12 @@ func (i *I18n) Tr(lang, format string, args ...interface{}) string {
 
 	loc := i.localizer.GetLocale(index)
 	if loc != nil {
-		return loc.GetMessage(format, args...)
+		msg := loc.GetMessage(format, args...)
+		if msg == "" && !i.Strict && index > 0 {
+			// it's not the default/fallback language and not message found for that lang:key.
+			return i.localizer.GetLocale(0).GetMessage(format, args...)
+		}
+		return msg
 	}
 
 	return fmt.Sprintf(format, args...)
@@ -374,7 +384,12 @@ func GetMessage(r *http.Request, format string, args ...interface{}) string {
 func (i *I18n) GetMessage(r *http.Request, format string, args ...interface{}) string {
 	loc := i.GetLocale(r)
 	if loc != nil {
-		return loc.GetMessage(format, args...)
+		// it's not the default/fallback language and not message found for that lang:key.
+		msg := loc.GetMessage(format, args...)
+		if msg == "" && !i.Strict && loc.Index() > 0 {
+			return i.localizer.GetLocale(0).GetMessage(format, args...)
+		}
+		return msg
 	}
 
 	return fmt.Sprintf(format, args...)

loader.go

@@ -142,6 +142,7 @@ func load(assetNames []string, asset func(string) ([]byte, error), options ...Lo
 
 			t := m.Languages[langIndex]
 			locales[langIndex] = &defaultLocale{
+				index:        langIndex,
 				id:           t.String(),
 				tag:          &t,
 				templateKeys: templateKeys,
@@ -189,14 +190,19 @@ func (l MemoryLocalizer) SetDefault(index int) bool {
 }
 
 type defaultLocale struct {
-	id  string
-	tag *language.Tag
+	index int
+	id    string
+	tag   *language.Tag
 	// templates *template.Template // we could use the ExecuteTemplate too.
 	templateKeys map[string]*template.Template
 	lineKeys     map[string]string
 	other        map[string]interface{}
 }
 
+func (l *defaultLocale) Index() int {
+	return l.index
+}
+
 func (l *defaultLocale) Tag() *language.Tag {
 	return l.tag
 }

loader_test.go

@@ -66,6 +66,13 @@ func testLoadAndTrHelper(t *testing.T, i18N *I18n) {
 	if expected := "ολοκλήρωση παραγγελίας - όλα"; got != expected {
 		t.Fatalf("expected %s but got %s", expected, got)
 	}
+
+	// test fallback default language's key.
+	got = i18N.Tr("el-GR", "KeyOnlyOnDefaultLang")
+	if expected := "value"; got != expected {
+		t.Fatalf("expected %s but got %s", expected, got)
+	}
+
 }
 
 func TestLoadEmptyTags(t *testing.T) {
@@ -74,5 +81,6 @@ func TestLoadEmptyTags(t *testing.T) {
 		t.Fatal(err)
 	}
 
+	i18N.SetDefault("en-US")
 	testLoadAndTrHelper(t, i18N)
 }

testfiles/en-US/other.json

@@ -1,4 +1,5 @@
 {
     "JSONTemplateExample": "value of {{.Value}}",
-    "TypeOf": "type of %T"
+    "TypeOf": "type of %T",
+    "KeyOnlyOnDefaultLang": "value"
 }