Astro.locals.i18n reference

Astro.locals.i18n is added by LightNet middleware. It is available in Astro pages, layouts, and components, so you can read locale metadata and resolve translated text without extra imports.

Use this API when rendering localized UI in .astro files.

t

type: t(key, options?) => string

Translates a translation key using the current locale.

• Use t() for translation keys from src/translations/*.yml and LightNet’s built-in translation files.
• If no supported locale is resolved from the URL pathname, LightNet falls back to the configured default locale before translating.
• The options argument follows i18next conventions, including interpolation, plurals, and context.
• If a key is truly undefined, t() throws an error.

---
const { t } = Astro.locals.i18n
---
<h1>{t("ln.404.page-not-found")}</h1>

{Astro.locals.i18n.t("some.key", { count: 2 })}

Use t() for UI strings such as headings, button labels, and other text defined in translation files.

Note

LightNet uses i18next internally, so t() supports features such as plurals, interpolation, and context using i18next conventions.

tMap

type: tMap(translationMap, context) => string

Resolves an inline translation map object for the current locale.

• Use tMap() for values that already contain localized text inline, such as config fields or content JSON.
• tMap() does not look up translation keys from translation files.
• It first tries currentLocale.
• If that value is missing, it falls back to defaultLocale.
• If neither locale has a value, tMap() throws an error.
• context.path is required so LightNet can point error messages to the exact config or content field.

Example translation map:

{
  en: "Hello",
  de: "Hallo"
}

---
const siteTitle = Astro.locals.i18n.tMap(config.title, {
  path: ["config", "title"],
})
---
<title>{siteTitle}</title>

Use tMap() when the localized values are already present in the object you are reading. Use t() when you have a translation key that should be looked up in translation files.

Locale metadata

currentLocale

type: string

The current locale resolved from the URL pathname. LightNet checks the first locale segment in the pathname and falls back to defaultLocale when the pathname does not contain a supported locale.

defaultLocale

type: string

The configured default locale. This is the code of the language with isDefaultSiteLanguage: true.

locales

type: string[]

The configured list of supported locales. This is the codes of the languages with isSiteLanguage: true.

direction

type: "ltr" | "rtl"

The text direction for the current locale. LightNet resolves this from the language settings for currentLocale.

translationKeys

type: string[]

The list of all available translation keys.

Best practices

• Use t() for translation-file keys.
• Use tMap() for inline localized objects from config or content.
• Avoid hard-coded UI strings when a translation key should be used instead.
• Use currentLocale and direction in markup when building locale-aware or RTL-aware UI.