i18next-parser

What is i18next-parser?

i18next-parser is a tool that extracts translation keys from your source code to JSON, allowing you to manage and maintain your internationalization (i18n) files more efficiently. It supports various file formats and can be integrated into your build process.

What are i18next-parser's main functionalities?

Extract Translation Keys

This feature allows you to extract translation keys from your source code files and generate JSON files for each locale. The code sample demonstrates how to use i18next-parser to parse JavaScript files in the 'src' directory and output the translations to 'locales/en/translation.json' and 'locales/fr/translation.json'.

const parser = require('i18next-parser');
const fs = require('fs');

const options = {
  locales: ['en', 'fr'],
  output: 'locales/$LOCALE/$NAMESPACE.json'
};

parser.parseFiles('src/**/*.js', options, (err, translations) => {
  if (err) throw err;
  fs.writeFileSync('locales/en/translation.json', JSON.stringify(translations.en, null, 2));
  fs.writeFileSync('locales/fr/translation.json', JSON.stringify(translations.fr, null, 2));
});

Support for Multiple File Formats

i18next-parser supports multiple file formats including JavaScript, JSX, TypeScript, and TSX. The code sample shows how to configure the parser to handle these different file types and extract translations from them.

const parser = require('i18next-parser');
const options = {
  input: ['src/**/*.js', 'src/**/*.jsx', 'src/**/*.ts', 'src/**/*.tsx'],
  output: 'locales/$LOCALE/$NAMESPACE.json'
};

parser.parseFiles(options.input, options, (err, translations) => {
  if (err) throw err;
  console.log('Translations extracted successfully');
});

Customizable Output

You can customize the output path and separators for namespaces and keys. The code sample demonstrates how to set a custom output path and define custom separators for namespaces and keys.

const parser = require('i18next-parser');
const options = {
  locales: ['en', 'de'],
  output: 'custom_locales/$LOCALE/$NAMESPACE.json',
  namespaceSeparator: ':',
  keySeparator: '.'
};

parser.parseFiles('src/**/*.js', options, (err, translations) => {
  if (err) throw err;
  console.log('Custom output path and separators applied');
});

Other packages similar to i18next-parser

babel-plugin-i18next-extract

babel-plugin-i18next-extract is a Babel plugin that extracts translation keys from your code and generates JSON files for i18next. It integrates directly with Babel, making it a good choice if you are already using Babel in your project. Compared to i18next-parser, it offers a more seamless integration with the Babel build process but may require more setup if you are not using Babel.

react-intl-translations-manager

react-intl-translations-manager is a tool for managing translations in projects using react-intl. It extracts messages from your React components and generates translation files. While it is specifically designed for use with react-intl, it offers similar functionality to i18next-parser in terms of extracting and managing translation keys. However, it is less flexible in terms of file format support and integration with non-React projects.

README

i18next Parser

When translating an application, maintaining the catalog by hand is painful. This package automate the process. Don't let the name fool you, it was originally built with i18next in mind but it works well with other i18n libraries.

Features

• Choose your weapon: A CLI, a standalone parser or a stream transform
• Three built in lexers: Javascript, HTML and Handlebars
• Creates one catalog file per locale and per namespace
• Backs up the old keys your code doesn't use anymore in namespace_old.json catalog.
• Restores keys from the _old file if the one in the translation file is empty.
• Supports i18next features:
  • Context: keys of the form key_context
  • Plural: keys of the form key_plural and key_plural_0
• Behind the hood, it's a stream transform (so it works with gulp)
• Supports es6 template strings (in addition to single/double quoted strings) with ${expression} placeholders

DISCLAMER: 1.0.0-beta

1.x is currently in beta. You can follow the pre-releases here. It is a deep rewrite of this package that solves many issues, the main one being that it was slowly becoming unmaintainable. The migration contains all the breaking changes. Everything that follows is related to 1.x. If you rely on a 0.x.x version, you can still find the old documentation on its dedicated branch.

Usage

CLI

You can use the CLI with the package installed locally but if you want to use it from anywhere, you better install it globally:

yarn global add i18next-parser@next
npm install -g i18next-parser@next
i18next 'app/**/*.{js,hbs}' 'lib/**/*.{js,hbs}' [-oc]

Multiple globbing patterns are supported to specify complex file selections. You can learn how to write globs here. Note that glob must be wrapped with single quotes when passed as arguments.

• -o, --output : Where to write the locale files.
• -c, --config : The config file with all the options
• -S, --silent: The config file with all the options

Gulp

Save the package to your devDependencies:

yarn add -D i18next-parser@next
npm install --save-dev i18next-parser

Gulp defines itself as the streaming build system. Put simply, it is like Grunt, but performant and elegant.

const i18next = require('i18next-parser');

gulp.task('i18next', function() {
  gulp.src('app/**')
    .pipe(i18next({
      locales: ['en', 'de'],
      output: '../locales'
    }))
    .pipe(gulp.dest('locales'));
});

IMPORTANT: output is required to know where to read the catalog from. You might think that gulp.dest() is enough though it does not inform the transform where to read the existing catalog from.

Options

Option	Description	Default
contextSeparator	Key separator used in your translation keys	_
createOldCatalogs	Save the _old files	true
defaultNamespace	Default namespace used in your i18next config	translation
defaultValue	Default value to give to empty keys	''
extension 1	Extenstion of the catalogs	.json
filename 1	Filename of the catalogs	'$NAMESPACE'
indentation	Indentation of the catalog files	2
keepRemoved	Keep keys from the catalog that are no longer in code	false
keySeparator 2	Key separator used in your translation keys	.
lexers	See below for details	{}
lineEnding	Control the line ending. See options at eol	auto
locales	An array of the locales in your applications	['en','fr']
namespaceSeparator 2	Namespace separator used in your translation keys	:
output	Where to write the locale files relative to the base	locales
reactNamespace 3	For react file, extract the defaultNamespace	false
sort	Whether or not to sort the catalog	false

1. Both filename and extension options support injection of $LOCALE and $NAMESPACE variables. The file output is JSON by default, if you want YAML, the extension must end with yml.
2. If you want to use plain english keys, separators such as . and : will conflict. You might want to set keySeparator: false and namespaceSeparator: false. That way, t('Status: Loading...') will not think that there are a namespace and three separator dots for instance.
3. If the file being parsed has a .jsx extension, this option is ignored and the namespace is being extracted.

Lexers

The lexers option let you configure which Lexer to use for which extension. Here is the default:

{
  lexers: {
    hbs: ['HandlebarsLexer'],
    handlebars: ['HandlebarsLexer'],

    htm: ['HTMLLexer'],
    html: ['HTMLLexer'],

    js: ['JavascriptLexer'],
    jsx: ['JavascriptLexer', 'JsxLexer'],
    mjs: ['JavascriptLexer'],

    default: ['JavascriptLexer']
  }
}

Note the presence of a default which will catch any extension that is not listed. There are 3 lexers available: HandlebarsLexer, HTMLLexer and JavascriptLexer. Each has configurations of its own. If you need to change the defaults, you can do it like so:

{
  lexers: {
    hbs: [
      {
        lexer: 'HandlebarsLexer',
        functions: ['translate', '__']
      }
    ],
    // ...
  }
}

HandlebarsLexer options

Option	Description	Default
functions	Array of functions to match	['t']

HTMLLexer options

Option	Description	Default
attr	Attribute for the keys	'data-i18n'
optionAttr	Attribute for the options	'data-i18n-options'

JavscriptLexer options

Option	Description	Default
functions	Array of functions to match	['t']

JsxLexer options

Option	Description	Default
attr	Attribute for the keys	i18nKey

Events

The transform emits a reading event for each file it parses:

.pipe( i18next().on('reading', (file) => {}) )

The transform emits a error:json event if the JSON.parse on json files fail:

.pipe( i18next().on('error:json', (path, error) => {}) )

The transform emits a warning:variable event if the file has a key that contains a variable:

.pipe( i18next().on('warning:variable', (path, key) => {}) )

Contribute

Any contribution is welcome. Please read the guidelines first.

Thanks a lot to all the previous contributors.