i18next-json-sync

Keeps i18next JSON resource files in sync against a primary
language, including plural forms. When hooked up to a build process/CI server, ensures keys
added/removed from one language are correctly propagated to the other languages, reducing the chance
for missing or obselete keys, merge conflicts, and typos.

Example

Given these files:
``
locales
├── en.json
├── fr.json
└── ru.json
`

`json
en.json
{
"key_one": "value",
"book": "book",
"book_plural": "books"
}

fr.json
{
"key_one": "french value"
}

ru.json
{
"extra_key": "extra value"
}
`


fr.json and ru.json can be synced against en.json:

`js
import sync from 'i18next-json-sync'
sync({
files: 'locales/*.json',
primary: 'en'
});
`

resulting in:

`json
en.json
{
"key_one": "value",
"book": "book",
"book_plural": "books"
}

fr.json
{
"key_one": "french value",
"book": "book",
"book_plural": "books"
}

ru.json
{
"key_one": "value",
"book_0": "books",
"book_1": "books",
"book_2": "books"
}
`

key_one was left alone in fr.json since it's already localized, but book and book_plural were copied over.
An extraneous key in ru.json was deleted and keys from en.json copied over. Plurals are mapped between
languages according to the i18next suffix rules.

> Note: Languages with only one suffix shared for singular and plural forms will not provide plural
mappings if they are used as the primary language.

This works on one folder at a time, but can deal with whatever the files glob returns. Files are
grouped into directories before processing starts. Folders without a 'primary' found are ignored.

Usage

$ npm install i18next-json-sync --save-dev

#### In node.js

`js
import sync from 'i18next-json-sync';
//or in ES5 world:
//const sync = require('i18next-json-sync').default;

//defaults are inline:
sync({
/** Audit files in memory instead of changing them on the filesystem and
throw an error if any changes would be made /
check: false,
/* Glob pattern for the resource JSON files /
files: '*/locales/.json',
/* An array of glob patterns to exclude from the files search /
excludeFiles: ['/node_modules/'],
/* Primary localization language. Other language files will be changed to match /
primary: 'en',
/* Language files to create if they don't exist, e.g. ['es, 'pt-BR', 'fr'] /
createResources: [],
/* Space value used for JSON.stringify when writing JSON files to disk /
space: 4,
/* Line endings used when writing JSON files to disk. Either LF or CRLF /
lineEndings: 'LF',
/* Insert a final newline when writing JSON files to disk /
finalNewline: false,
/* Use empty string for new keys instead of the primary language value /
newKeysEmpty: false
})
`

#### CLI

It can be installed globally and run with sync-i18n, but package.json scripts are a better fit.

`json
{
"name": "my-app",
"scripts": {
"i18n": "sync-i18n --files '*/locales/.json' --primary en --languages es fr ja zh ko --space 2",
"check-i18n": "npm run i18n -- --check"
}
}
`

Then use npm run i18n to sync on the filesystem and npm run check-i18n to validate.

All options are available via CLI. Use -h or --help` to get help output.

License

MIT