How to use jinja2 and its i18n extension (using babel) outside flask

Question

How can I use jinja2 with babel outside a flask application. Supposing that I have locale dir which is populated using pybabel command. I want to load translation files and translate my template files.

Answer 1

I found the solution. Here's how you can use jinja2/babel without flask integration.

Preconditions

Preconditions are described just to complete the example, all of them can have other values or names.

You use message domain named "html" for messages (domain is arbitrary name, default is "message").

There is a directory "i18n" with translated and compiled messages (e.g. with a file i18n/cs/LC_MESSAGES/html.mo).

You prefer to render your templates using "cs" or "en" locale.

The templates are located in directory templates and there exists a jinja2 template named stack.html there, so there exists a file templates/stack.html.

Code sample

from jinja2 import Environment, FileSystemLoader
from babel.support import Translations

locale_dir = "i18n"
msgdomain = "html"
list_of_desired_locales = ["cs", "en"]
loader = FileSystemLoader("templates")
extensions = ['jinja2.ext.i18n', 'jinja2.ext.autoescape', 'jinja2.ext.with_']

translations = Translations.load(locale_dir, list_of_desired_locales)
env = Environment(extensions=extensions, loader=loader) # add any other env options if needed
env.install_gettext_translations(translations)

template = env.get_template("stack.html")
rendered_template = template.render()

The rendered_template contains the rendered HTML content now, probably in "cs" locale.

Answer 2

This works great! Thanks.

I. jinja2 dependency MarkupSafe

II. Python babel dependency ytz

See for these steps at http://tlphoto.googlecode.com/git/jinja2_i18n_howto.txt

1. Create the folder structure (no whitespace after the commas!!!)

   mkdir -pv ./lang/{en_US,zh_CN,fa_IR,es_VE,de_DE,ja_JP}/LC_MESSAGES/

2. Extract

   pybabel -v extract -F babel.config -o ./lang/messages.pot ./

3. Init/Update

   3.1 Init

   pybabel init -l zh_CN -d ./lang -i ./lang/messages.pot

   3.2 Update

   pybabel update -l zh_CN -d ./lang -i ./lang/messages.pot

4. Compile

   pybabel compile -f -d ./lang