Json and translation

Question

I have a json document where some of the strings must be translated. For example (made-up syntax), my data.json:

{
  "greeting": "trans:Hello"
}

In this case the string "Hello" is marked as translatable with the prefix trans: (which does not seem very robust). I would then use a tool to generate a catalog:

xgettext data.json

And then translate the strings to my target languages. My application will then use my original json and the translations mapping:

translations = {
  "en" : {
    "Hello": "Hello"
  },
  "es" : {
    "Hello": "Hola"
  }
}

And would generate the final json (for target language es):

{
  "greeting": "Hola"
}

Is there any standard way of specifying translatable strings in json, so that they can be processed by standard tools to generate message catalogs?

Answer 1

You can use the appropriate gettext language preprocessor to extract strings which are marked, usually with _(string) or gettext(string), and create a gettext catalog (POT file) containing those strings. After you create a localized version of the catalog for a particular language, probably using a tool such as poedit, in this case you would then convert it into a JSON representation--for more information, and for ideas about standard ways to handle gettext-style message catalogs in JavaScript, take a look at JED--and then load this JSON-formatted catalog into your app at run-time, and access it via utilities defined for that purpose.

The notation _(string) has two effects. First, it marks the string for the extractor. Second, at run-time it invokes a function called _ to look up the string in the catalog and returns the localized value.

The problem with JSON is that obviously _(string) is invalid JSON syntax. If possible, consider changing this from a JSON file to a JS file containing an object.