Manual:GenerateJsonI18n.php

Details
generateJsonI18n.php file is a maint-scripts>Special:MyLanguage/Manual:Maintenance scripts|maintenance script to generate JSON-formatted i18n files from legacy PHP array-based mediawiki i18n files.

Usage
php maintenance/generateJsonI18n.php phpfile jsondir

where:

PHP file defining a $messages array. Required unless  is provided. directory to write the JSON files to. Will default to.
 * phpfile -
 * jsondir -

Example
Alternate way for extensions, since : This example performs the default conversions in  , replacing the   file with a backwards-compatibility shim and porting messages to the   directory.

Suggested migration process
If your extension has not been converted already.
 * Make sure you have the latest code
 * Create the i18n directory
 * Run the script
 * Update your extension's entry file to add ['YourExtension'] = __DIR__ . '/i18n';
 * Commit it to gerrit if the extension is hosted there
 * Add Siebrand and Raimond as reviewers if the extension is translated in translatewiki.net
 * Wait for review and all should go smoothly