Kay i18n mechanism

Overview

Kay has a almost full stack i18n feature including extracting messages from the source, adding new language to your app, updating and compiling the message catalogs and a handlers for javascript gettext implementation. This feature is basicaly based on the jinja2’s i18n feature, so it is a good idea to refer to jinja2’s documentation hosted at:

http://jinja.pocoo.org/2/documentation/

Kay automatically detects user’s language by parsing Accept-Language header sent by user’s browser. You can also create a link for setting preffered language in user’s cookie which overrides Accept-Language setting.

Marking your messages

You can mark your messages for translation in python code as following:

from kay.i18n import gettext as _
_('Hello')

You can mark your messages for translation in templates as following:

<p>{{ _('Hello') }}</p>
<p>{% trans %}Hello{% endtrans %}

Extracting messages

You can extract the messages from myapp application and create the template catalog file as following:

$ python manage.py extract_messages myapp

The extract_messages subcommand accepts optional --domain parameter. The value for this parameter must be messages or jsmessages.

Adding translations

You can add new Japanese translations from the template like:

$ python manage.py add_translations myapp -l ja

Updating messages

You can update your translations with updated translation template as following:

$ python manage.py update_translations myapp -l ja

Compiling messages

You can compile all of your translations under myapp application as following:

$ python manage.py compile_translations myapp

Create a link for setting language

There is a function for creating a URL that will set preffered language in user’s cookie. To use this capability, you need to add kay.i18n to INSTALLED_APPS attribute as follows:

INSTALLED_APPS = (
  'kay.i18n',
)

In jinja2 context, create_lang_url function is automatically loaded. So you can use this function for creating a link for setting language explicitly as follows:

<a href="{{ create_lang_url(lang='en') }}">{{ _('English') }}</a>
<a href="{{ create_lang_url(lang='ja') }}">{{ _('Japanese') }}</a>

Javascript handler

You can define a handler for pseudo javascript gettext as following:

from kay.views.i18n import javascript_catalog

return Map([
  Rule('/_i18n.js', endpoint='i18n_js',
       defaults={'packages':('myapp','kay')}),
])

all_views = {
  'i18n_js': javascript_catalog,
}