add LoadKV method on Iris.Application.I18N instance

i18n/loader.go

@@ -73,6 +73,70 @@ func FS(fileSystem fs.FS, pattern string, options LoaderConfig) (Loader, error)
 	return load(assetNames, assetFunc, options), nil
 }
 
+// LangMap key as language (e.g. "el-GR") and value as a map of key-value pairs (e.g. "hello": "Γειά").
+type LangMap = map[string]map[string]interface{}
+
+// KV is a loader which accepts a map of language(key) and the available key-value pairs.
+// Example Code:
+//
+//	m := i18n.LangMap{
+//		"en-US": map[string]interface{}{
+//			"hello": "Hello",
+//		},
+//		"el-GR": map[string]interface{}{
+//			"hello": "Γειά",
+//		},
+//	}
+//
+// app := iris.New()
+// [...]
+// app.I18N.LoadKV(m)
+// app.I18N.SetDefault("en-US")
+func KV(langMap LangMap, opts ...LoaderConfig) Loader {
+	return func(m *Matcher) (Localizer, error) {
+		options := DefaultLoaderConfig
+		if len(opts) > 0 {
+			options = opts[0]
+		}
+
+		languageIndexes := make([]int, 0, len(langMap))
+		keyValuesMulti := make([]map[string]interface{}, 0, len(langMap))
+
+		for languageName, pairs := range langMap {
+			langIndex := parseLanguageName(m, languageName) // matches and adds the language tag to m.Languages.
+			languageIndexes = append(languageIndexes, langIndex)
+			keyValuesMulti = append(keyValuesMulti, pairs)
+		}
+
+		cat, err := internal.NewCatalog(m.Languages, options)
+		if err != nil {
+			return nil, err
+		}
+
+		for _, langIndex := range languageIndexes {
+			if langIndex == -1 {
+				// If loader has more languages than defined for use in New function,
+				// e.g. when New(KV(m), "en-US") contains el-GR and en-US but only "en-US" passed.
+				continue
+			}
+
+			kv := keyValuesMulti[langIndex]
+			err := cat.Store(langIndex, kv)
+			if err != nil {
+				return nil, err
+			}
+		}
+
+		if n := len(cat.Locales); n == 0 {
+			return nil, fmt.Errorf("locales not found in map")
+		} else if options.Strict && n < len(m.Languages) {
+			return nil, fmt.Errorf("locales expected to be %d but %d parsed", len(m.Languages), n)
+		}
+
+		return cat, nil
+	}
+}
+
 // DefaultLoaderConfig represents the default loader configuration.
 var DefaultLoaderConfig = LoaderConfig{
 	Left:               "{{",
@@ -88,7 +152,7 @@ var DefaultLoaderConfig = LoaderConfig{
 // and any Loader options.
 // It returns a valid `Loader` which loads and maps the locale files.
 //
-// See `Glob`, `Assets` and `LoaderConfig` too.
+// See `FS`, `Glob`, `Assets` and `LoaderConfig` too.
 func load(assetNames []string, asset func(string) ([]byte, error), options LoaderConfig) Loader {
 	return func(m *Matcher) (Localizer, error) {
 		languageFiles, err := m.ParseLanguageFiles(assetNames)