🧪 astro-i18next

An astro integration of i18next + some utility components to help you translate your astro websites!

Note

Status - 🚧 Beta

👉 Road to v1.0.0

You can use it, and feedback is more than welcome! Note that some breaking changes may still be introduced during this phase as the goal for v1 is to get the best possible DX for translating your Astro pages.

🚀 Getting started
💻 CLI commands
- generate
📦 Utility components
📦 Utility functions
👀 Going further
- Namespaces
- AstroI18nextConfig Props
✨ Contributors
📜 License

🚀 Getting started

1. Install

npm install astro-i18next

2. Configure

Add astro-i18next to your astro.config.mjs:

import { defineConfig } from "astro/config";
import astroI18next from "astro-i18next";

export default defineConfig({
  integrations: [astroI18next()],
});

Configure astro-i18next in your astro-i18next.config.mjs file:

/** @type {import('astro-i18next').AstroI18nextConfig} */
export default {
  defaultLanguage: "en",
  supportedLanguages: ["en", "fr"],
  i18next: {
    debug: true, // convenient during development to check for missing keys
    resources: {
      en: {
        translation: {
          key: "hello world",
        },
      },
      fr: {
        translation: {
          key: "bonjour le monde",
        },
      },
    },
  },
};

ℹ️ Your astro-i18next config file can be a javascript (.js | .mjs | .cjs) or typescript (.ts | .mts | .cts) file.

ℹ️ For a more advanced configuration, see the AstroI18nextConfig props.

(recommended) Load translation keys using an i18next backend plugin. For instance with the i18next-fs-backend plugin to load translation keys from the filesystem:

npm install i18next-fs-backend

  src
  ├-- locales  # create this folder to store your translation strings
  |   |-- en.json      # english translation strings
  |   └-- fr.json      # french translation strings
  └-- pages
      └-- index.astro  # route for default language

/** @type {import('astro-i18next').AstroI18nextConfig} */
export default {
  defaultLanguage: "en",
  supportedLanguages: ["en", "fr"],
  i18next: {
    debug: true,
    initImmediate: false,
    backend: {
      loadPath: "./src/locales/{{lng}}.json",
    },
  },
  i18nextPlugins: { fsBackend: "i18next-fs-backend" },
};

ℹ️ You may choose to organize your translations into multiple files instead of a single file per language using namespaces.

3. Start translating

You may now start translating your pages by using i18next's t function or the Trans component depending on your needs.

Here's a quick tutorial to get you going:

Use translation keys in your Astro pages

---
// src/pages/index.astro
import i18next, { t } from "i18next";
import { Trans, HeadHrefLangs } from "astro-i18next/components";
---

<html lang={i18next.language}>
  <head>
    <meta charset="utf-8" />
    <meta name="viewport" content="width=device-width" />
    <title>{t("site.title")}</title>
    <meta name="description" content={t("site.description")} />
    <HeadHrefLangs />
  </head>
  <body>
    <h1>{t("home.title")}</h1>
    <p>
      <Trans i18nKey="home.subtitle">
        This is a <em>more complex</em> string to translate, mixed with <strong
          >html elements
        </strong> such as <a href="https://example.com/">a cool link</a>!
      </Trans>
    </p>
  </body>
</html>

// src/locales/en.json
{
  "site": {
    "title": "My awesome website!",
    "description": "Here is the description of my awesome website!"
  },
  "home": {
    "title": "Welcome to my awesome website!",
    "subtitle": "This is a <0>more complex</0> string to translate, mixed with <1>html elements</1>, such as a <2>a cool link</2>!"
  }
}

// src/locales/fr.json
{
  "site": {
    "title": "Mon super site web !",
    "description": "Voici la description de mon super site web !"
  },
  "home": {
    "title": "Bienvenue sur mon super site web !",
    "subtitle": "Ceci est une chaine de charactères <0>plus compliquée</0> à traduire, il y a des <1>éléments html</1>, comme <2>un super lien</2> par exemple !"
  }
}

Create localized pages using the generate command
```
npx astro-i18next generate
```
You're all set! Have fun translating and generate localized pages as you go 🚀

Note

For a real world example, see the demo project or try the Astro i18n basics example on StackBlitz:

💻 CLI commands

generate

npx astro-i18next generate

This command will generate localized pages depending on your config and set i18next's language change on each page.

For instance, with supportedLanguages = ["en", "fr", "es"], and "en" being the default language and having:

src
└-- pages
    |-- about.astro
    └-- index.astro

👇 Running npx astro-i18next generate will create the following pages

src
└-- pages
    |-- es
    |   |-- about.astro
    |   └-- index.astro
    |-- fr
    |   |-- about.astro
    |   └-- index.astro
    |-- about.astro
    └-- index.astro

📦 Utility components

Trans component

A component that takes care of interpolating its children with the translation strings. Inspired by react-i18next's Trans component.

---
import { Trans } from "astro-i18next/components";
---

<Trans i18nKey="superCoolKey">
  An <a href="https://astro.build" title="Astro website">astro</a> integration of
  <a href="https://www.i18next.com/" title="i18next website">i18next</a> and utility
  components to help you translate your astro websites!
</Trans>

// fr.json
{
  "superCoolKey": "Une intégration <0>astro</0> d'<1>i18next</1> + quelques composants utilitaires pour vous aider à traduire vos sites astro !"
}

Trans Props

Prop name	Type (default)	Description
i18nKey	string (undefined)	Internationalization key to interpolate to. Can contain the namespace by prepending it in the form 'ns:key' (depending on i18next.options.nsSeparator)
ns	?string (undefined)	Namespace to use. May also be embedded in i18nKey but not recommended when used in combination with natural language keys.

LanguageSelector component

Unstyled custom select component to choose amongst supported locales.

---
import { LanguageSelector } from "astro-i18next/components";
---

<LanguageSelector showFlag={true} class="my-select-class" />

LanguageSelector Props

Prop name	Type (default)	Description
showFlag	?boolean (`false`)	Choose to display the language emoji before language name

HeadHrefLangs component

HTML tags to include in your page's <head> section to let search engines know about its language and region variants. To know more, see Google's advanced localized versions.

---
import i18next from "i18next";
import { HeadHrefLangs } from "astro-i18next/components";
---

<html lang={i18next.language}>
  <head>
    <meta charset="utf-8" />
    <meta name="viewport" content="width=device-width" />
    <title>...</title>
    <meta name="description" content="..." />
    <HeadHrefLangs />
  </head>
  <body>...</body>
</html>

The HeadHrefLangs component will generate all of the alternate links depending on the current url and supported languages.

For example, if you are on the /about page and support 3 languages (en, fr, es) with en being the default language, this will render:

<link rel="alternate" hreflang="en" href="https://www.example.com/about/" />
<link rel="alternate" hreflang="fr" href="https://www.example.com/fr/about/" />
<link rel="alternate" hreflang="es" href="https://www.example.com/es/about/" />

📦 Utility functions

interpolate function

interpolate(i18nKey: string, reference: string, namespace: string | null): string

astro-i18next exposes the logic behind the Trans component, you may want to use it directly.

import { interpolate } from "astro-i18next";

const interpolated = interpolate(
  "superCoolKey",
  'An <a href="https://astro.build" title="Astro website">astro</a> integration of <a href="https://www.i18next.com/" title="i18next website">i18next</a> and utility components to help you translate your astro websites!'
);

localizePath function

localizePath(path: string, locale: string | null = null, base: string = import.meta.env.BASE_URL): string

Sets a path within a given locale. If the locale param is not specified, the current language will be used.

Note: This should be used instead of hard coding paths to other pages. It will take care of setting the right path depending on the locale you set.

---
import { localizePath } from "astro-i18next";
import i18next from "i18next";

i18next.changeLanguage("fr");
---

<a href={localizePath("/about")}>...</a>
<!-- renders: <a href="/fr/about">...</a> -->

localizeUrl function

localizeUrl(url: string, locale: string | null = null, base: string = import.meta.env.BASE_URL): string

Sets a url within a given locale. If the locale param is not specified, the current language will be used.

Note: This should be used instead of hard coding urls for internal links. It will take care of setting the right url depending on the locale you set.

---
import { localizeUrl } from "astro-i18next";
import i18next from "i18next";

i18next.changeLanguage("fr");
---

<a href={localizeUrl("https://www.example.com/about")}>...</a>
<!-- renders: <a href="https://www.example.com/fr/about">...</a> -->

👀 Going further

Namespaces

i18next allows you to organize your translation keys into namespaces.

Using the i18next-fs-backend plugin, it can easily be setup in your backend.loadPath option like so:

/** @type {import('astro-i18next').AstroI18nextConfig} */
export default {
  defaultLanguage: "en",
  supportedLanguages: ["en", "fr"],
  i18next: {
    debug: true,
    initImmediate: false,
    backend: {
      loadPath: "./src/locales/{{lng}}/{{ns}}.json", // will look for json files inside language folders
    },
  },
  i18nextPlugins: { fsBackend: "i18next-fs-backend" },
};

You can see i18next-fs-backend's documentation for more info.

Then, let's say you have a translation file under ./src/locales/{{lng}}/home.json, you may use the t() function or the Trans component by setting the namespace (home here):

---
import { t } from "i18next";
import { Trans } from "astro-i18next/components";
---

<h1>{t("home:myHomeTitle")}</h1>
<p>
  <Trans i18nKey="myHomeDescription" ns="home">
    This translation was retrieved using the <strong>home</strong> namespace!
    <Trans />
  </Trans>
</p>

You can have as many namespaces as you wish, have one per page and one for common translation strings for example:

src
 ├-- locales
 |   |-- en
 |   |   |-- about.json    # "about" namespace
 |   |   |-- common.json   # "common" namespace
 |   |   └-- home.json     # "home" namespace
 |   └-- fr   # same in files other language folders
 └-- pages
      |-- about.astro
      └-- index.astro

AstroI18nextConfig Props

astro-i18next's goal is to abstract most of the configuration for you so that you don't have to think about it. Just focus on translating!

Though if you'd like to go further in customizing i18next, feel free to tweak your config!

Prop name	Type (default)	Description
defaultLanguage	`string` (undefined)	The default language for your website
supportedLanguages	`string[]` (undefined)	Your website's supported languages
i18next	`?InitOptions`	The i18next configuration. See i18next's documentation.
i18nextPlugins	`?{[key: string]: string}`	Set i18next plugins. See i18next's available plugins.

✨ Contributors

Thanks goes to these wonderful people (emoji key):

_{Yassine Doghri} 💻 📖 🤔 🎨 💡 🚧	_{Davide Ceschia} 💻 🐛	_preetamslot 🐛	_Dmytro 🐛	_{Campbell He} 🐛	_MelKam 💻	_L1lith 🐛 🤔
_Anomander43 📖	_{Dominik Schöni} 💻