Avoiding extra request for the translation of a CKEditor plugin

When you write a plugin for CKEditor, it's almost for sure that it will include some text, it can be the tooltip for the toolbar button, a context menu entry or some change to one dialog, and you can leave that string hardcoded in your language, but it's usually better to use the localization features of CKEditor so it's easy for users in other countries to use your plugin, as well as allowing to easily change the text to fit better in a different environment.

As you might know this is achieved by setting a "lang" property in your plugin that it's an array with the list of language codes that your plugin provides:

 lang : [ 'en', 'es' ],

That entry tells CKEditor to load the file with the translation from the lang file of your plugin (lang/en.js or lang/es.js), and it's a pity that with all the current efforts about improving performance, due to the desire to provide the translation your editor might load slightly worse as it gets that extra file.

But there's an easy workaround, you can put the localization in the plugin.js file itself, so that when it checks what does it needs to load for this plugin, it can see that the translations are ready and so it skips for the next item.

Now each translation is just a line in the plugin and it doesn't require an extra request to the server:

CKEDITOR.plugins.setLang( 'backgrounds', 'en', { backgrounds : { label : 'Background image'} } );
CKEDITOR.plugins.setLang( 'backgrounds', 'es', { backgrounds : { label : 'Imagen de fondo'} } );