Dynamic Javascript using Scala template

Question

I am trying to localize my Javascript files. For instance, I would have:

var count = 0;
$('#choices .choice').each(function(i) {
    $('input', this).each(function() {
        count++
        $(this).attr('placeholder', '@Message("placeholder.choice") ' + count)
    })
})

This would obviously work if the Javascript file is inside the Scala HTML template but I would prefer to have it in a dedicated file.

To begin with, I am wondering if it is a good idea: what about caching file if it's content may change? In this case, there is a single parameter: having it in the URL would solve this problem? Eg: /assets/javascripts/:lang/my-file.js.

And the real question is: is it possible to do that using Play! framework? It does not seem that Javascript templates are supported (or I missed something). Is there a way to do it correctly?

Answer 1

Actually you don't need to translate your JavaScripts dynamically, it's reduntant waste of resources, instead prepare static JS files like messages.en.js, messages.de.js etc and include required file basing on the user's language directly into the view.

Here you have some description how to make it easy (JavaScript approach)

Answer 2

There is a module allowing javascript internationalization using the same mechanism as in Play templates, have a look at : https://github.com/julienrf/play-jsmessages

This will definitely fits your needs. I use it for a while know with success. You can expose your translations through a javascript file and then use browser caching with a proper fingerprinting configuration.