Source code for tet.i18n

"""
Internationalization support for Tet applications.

This module provides i18n/l10n integration including:

- Automatic ``_()`` and ``gettext()`` functions in templates
- ``ngettext()`` for pluralization
- Request methods for translation (``request.translate``, ``request.pluralize``)

Example
-------

Enabling i18n::

    from tet.config import application_factory

    @application_factory(included_features=["i18n"])
    def main(config):
        config.add_translation_dirs("myapp:locale")
        config.scan()

Using translations in views::

    from pyramid.view import view_config

    @view_config(route_name="hello", renderer="json")
    def hello(request):
        return {"message": request.translate("Hello, World!")}

In Tonnikala templates::

    <p>${_("Welcome to our site!")}</p>
    <p>${ngettext("1 item", "{n} items", count, mapping={"n": count})}</p>
"""
import sys

from pyramid.config import Configurator
from pyramid.i18n import TranslationStringFactory, get_localizer
from pyramid.threadlocal import get_current_request




def add_renderer_globals(event):
    """
    Subscriber that adds i18n functions to renderer globals.

    Adds ``_``, ``gettext``, ``ngettext``, and ``localizer`` to the template context.
    """
    request = event.get("request")

    if request is None:
        request = get_current_request()

    event["_"] = request.translate
    event["gettext"] = request.translate
    event["ngettext"] = request.pluralize
    event["localizer"] = request.localizer





def configure_i18n(config: Configurator, default_domain: str):
    """
    Configure i18n support for a Pyramid application.

    Adds ``request.translate`` and ``request.pluralize`` methods, and
    registers subscribers to add i18n functions to template contexts.

    :param config: Pyramid Configurator
    :param default_domain: Default translation domain
    """
    config.add_subscriber(add_renderer_globals, "pyramid.events.BeforeRender")
    config.add_subscriber(add_renderer_globals, "tet.viewlet.IBeforeViewletRender")

    config.registry.tsf = tsf = TranslationStringFactory(default_domain)

    def translate(request):
        localizer = request.localizer

        def auto_translate(string, *, domain=default_domain, mapping=None, context=None):
            if isinstance(string, str):
                string = tsf(string, context=context)

            return localizer.translate(string, domain=domain, mapping=mapping)

        return auto_translate

    def pluralize(request):
        localizer = request.localizer

        def auto_pluralize(singular, plural, n, *, domain=default_domain, mapping=None, context=None):
            if isinstance(singular, str):
                singular = tsf(singular, context=context)

            return localizer.pluralize(singular, plural, n, domain=domain, mapping=mapping)

        return auto_pluralize

    config.add_request_method(translate, property=True, reify=True)
    config.add_request_method(pluralize, property=True, reify=True)
    config.add_request_method(get_localizer, name='localize', property=True, reify=True)





def includeme(config: Configurator):
    """
    Pyramid includeme function for i18n support.

    Uses ``default_i18n_domain`` setting or the package name as the domain.
    """
    default_domain = config.get_settings().get(
        "default_i18n_domain", config.package.__name__
    )
    configure_i18n(config, default_domain)