i18n

Overview ¶

Package i18n is a handler and helper for the core (https://godoc.org/github.com/volatile/core). It provides internationalization functions following the client preferences.

Set translations ¶

A translation is associated to a key, which is associated to a language tag, which is part of Locales map.

All translations can be stored like this:

var locales = i18n.Locales{
	language.English: {
		"decimalMark":   ".",
		"thousandsMark": ",",

		"hello":         "Hello %s,",
		"how":           "How are you?",
		"basementZero":  "All the money hidden in your basement has been spent.",
		"basementOne":   "A single dollar remains in your basement.",
		"basementOther": "You have " + i18n.TnPlaceholder + " bucks in your basement.",
	},
	language.French: {
		"decimalMark":   ",",
		"thousandsMark": " ",

		"hello":         "Bonjour %s,",
		"how":           "Comment allez-vous?",
		"basementZero":  "Tout l'argent caché dans votre sous-sol a été dépensé.",
		"basementOne":   "Un seul dollar se trouve dans votre sous-sol.",
		"basementOther": "Vous avez " + i18n.TnPlaceholder + " briques dans votre sous-sol.",
	},
}

decimalMark and thousandsMark are special keys that define the digits separators for decimals and thousands when using Tn or Fmtn.

With these translations, you need to Init this package (the second argument is the default locale):

i18n.Init(locales, language.English)

Detect client locale ¶

When a client makes a request, the best locale must be matched to his preferences. To achieve this, you need to Use the handler with one or more matchers:

i18n.Use(i18n.MatcherFormValue, i18n.MatcherAcceptLanguageHeader)

The client locale is set as soon as a matcher is confident.

A matcher is a function that returns the locale parsed from core.Context with its level of confidence. These ones are actually available: MatcherAcceptLanguageHeader and MatcherFormValue.

Use translations ¶

A translation can be accessed with T, receiving the core.Context (which contains the matched locale), the translation key, and optional arguments (if the translation contains formatting verbs):

i18n.T(c, "hello", "Walter White")
i18n.T(c, "how")

If a translation has pluralized forms, you can use Tn and the most appropriate form will be used according to the quantity:

i18n.Tn(c, "basement", 333000.333)

will result in "You have 333,000.333 bucks in your basement.".

If you use templates, TemplatesFuncs provides a map of all usable functions. Example with package response (https://godoc.org/github.com/volatile/response) package:

response.TemplatesFuncs(i18n.TemplatesFuncs)