Vue.js Internationalisation (i18n) with vue-i18n and Intlayer

Table of Contents

What is Intlayer?

Intlayer is an innovative, open-source internationalisation library designed to address the shortcomings of traditional i18n solutions. It offers a modern approach to content management in Vue.js and Nuxt applications.

See a concrete comparison with vue-i18n in our vue-i18n vs. Intlayer blog post.

Why Combine Intlayer with vue-i18n?

While Intlayer provides an excellent standalone i18n solution (see our Vue.js integration guide), you might want to combine it with vue-i18n for several reasons.

Intlayer offers a rich set of advanced features that go beyond traditional i18n tools. It helps you:

• Automatically detect and fill missing translations to streamline localization.
• Test and validate your translations directly in your development or CI/CD workflows.
• Manage content per component, enabling a clean, scalable, and maintainable structure across your app.
• Externalize your content, making it easily editable by your whole team (developers, translators, and content managers).

However, vue-i18n remains an excellent and widely adopted i18n solution thanks to its mature ecosystem, broad community support, and extensive plugin compatibility.

By combining Intlayer with vue-i18n, you get the best of both worlds, vue-i18n’s stability and ecosystem maturity, with Intlayer’s modern content management, automation, and developer experience improvements.

This guide explains how to leverage Intlayer as an adapter for vue-i18n, allowing you to:

• Gradually migrate from vue-i18n to Intlayer.
• Keep existing vue-i18n plugins and workflows.
• Automate your JSON translations in CLI or CI/CD pipelines.
• Test, sync, and manage translations more effectively.

Step-by-Step Guide to Set Up Intlayer with vue-i18n

Step 1: Install Dependencies

Install the necessary packages using your preferred package manager:

npm install intlayer @intlayer/sync-json-plugin --save-devnpx intlayer init

Package explanations:

• intlayer: Core library for content declaration and management
• @intlayer/sync-json-plugin: Plugin to synchronise Intlayer content declarations to vue-i18n JSON format

Step 2: Implement the Intlayer plugin to wrap the JSON

Create an Intlayer configuration file to define your supported locales:

If you also want to export JSON dictionaries for vue-i18n, add the syncJSON plugin:

import { Locales, type IntlayerConfig } from "intlayer";import { syncJSON } from "@intlayer/sync-json-plugin";const config: IntlayerConfig = {  internationalization: {    locales: [Locales.ENGLISH, Locales.FRENCH, Locales.SPANISH],    defaultLocale: Locales.ENGLISH,  },  plugins: [    syncJSON({      format: "vue-i18n",      source: ({ key, locale }) => `./src/locales/${locale}/${key}.json`,    }),  ],};export default config;

The syncJSON plugin will automatically wrap the JSON. It will read and write the JSON files without changing the content architecture.

If you want to make that JSON coexist with Intlayer content declaration files (.content files), Intlayer will proceed as follows:

1. load both JSON and content declaration files and transform them into an Intlayer dictionary.2. if there are conflicts between the JSON and the content declaration files, Intlayer will merge all those dictionaries. This depends on the priority of the plugins, and that of the content declaration file (all are configurable).

If changes are made using the CLI to translate the JSON, or using the CMS, Intlayer will update the JSON file with the new translations.

To see more details about the syncJSON plugin, please refer to the syncJSON plugin documentation.

Git Configuration

Exclude generated files from version control:

# Ignore files generated by Intlayer.intlayer

These files are automatically regenerated during the build process and do not need to be committed to your repository.

VS Code Extension

For improved developer experience, install the official Intlayer VS Code Extension:

Install from the VS Code Marketplace

Install from the VS Code Marketplace