Difference between revisions of "I18NSupport"

Latest revision as of 04:29, 7 October 2013

Old Design Page This page was used to help design a feature that has been implemented. As a result, this page is unlikely to be updated and could contain outdated information. It was last updated on 2013-10-07

• Launchpad Entry: NovaSpec:i18n-support
• Created: 2010-10-22
• Contributors: Koji Iida, Hisaharu Ishii

http://etherpad.openstack.org/I18N-Support

Summary

• Internationalization support for logging messages
• Support Japanese messages

Release Note

• TBD

Rationale

• Currently, log messages are written only in English.
• I18N support is required for world-wide use of OpenStack.

User stories

• TBD

Assumptions

• Server side logging messages only
• Use launchpad function https://help.launchpad.net/Translations to manage translations.

Design

• Replace existing source code for log message output to I18N style by using gettext module.
• Provide Japanese message catalog (.po) files.

Implementation

JayPipes has already begun the i18n process for the OpenStack-CI project. He will provide assistance on automating the upload of the message catalog to Launchpad translations unit.

UI Changes

• No UI changes.

Code Changes

The followings are sample implementation step.

1. Install the function _() in Python’s builtin namespace.

Example: nova/nova-scheduler:

    import os
    import sys
+   import gettext

    # If ../nova/__init__.py exists, add ../ to Python search path, so that
    # it will override what happens to be installed in /usr/(local/)lib/python...
    possible_topdir = os.path.normpath(os.path.join(os.path.abspath(sys.argv[0]),
                                       os.pardir,
                                       os.pardir))
    if os.path.exists(os.path.join(possible_topdir, 'nova', '__init__.py')):
        sys.path.insert(0, possible_topdir)

    from nova import service
    from nova import twistd

+   gettext.install('nova', './locale', unicode=1)
+
    if __name__ == '__main__':
        twistd.serve(__file__)

    if __name__ == '__builtin__':
        application = service.Service.create()

2. Mark the strings which are used in logging function, by wrapping them in a call to the _() function.

Example: ./nova/service.py

         if not periodic_interval:
              periodic_interval = FLAGS.periodic_interval
-        logging.warn("Starting %s node", topic)
+        logging.warn(_("Starting %s node"), topic)
         service_obj = cls(host, binary, topic, manager,
                            report_interval, periodic_interval)

3. Generate .pot file.

$ pygettext -p locale -d nova nova/service.py

File locale/nova.pot generated.

4. Copy nova.pot to nova.po.

$ cp locale/nova.pot locale/ja/LC_MESSAGES/nova.po

5. Translate locale/ja/LC_MESSAGES/nova.po to your language.

Example translation of locale/ja/LC_MESSAGES/nova.po to Japanese:

# SOME DESCRIPTIVE TITLE.
# Copyright (C) YEAR ORGANIZATION
# FIRST AUTHOR <EMAIL@ADDRESS>, YEAR.
#
msgid ""
msgstr ""
"Project-Id-Version: 0.1\n"
"POT-Creation-Date: 2010-10-27 17:50+JST\n"
"PO-Revision-Date: 2010-10-27 18:13+JST\n"
"Last-Translator: Someone <iida.koji@example.com>\n"
"Language-Team: LANGUAGE <LL@li.org>\n"
"MIME-Version: 1.0\n"
"Content-Type: text/plain; charset=UTF-8\n"
"Content-Transfer-Encoding: 8bit\n"
"Generated-By: pygettext.py 1.5\n"


#: nova/service.py:141
msgid "Starting %s node"
msgstr "%s ノードを開始します"

6. Generate .mo file.

$ msgfmt -o locale/ja/LC_MESSAGES/nova.mo locale/ja/LC_MESSAGES/nova.po

File ./locale/ja/LC_MESSAGES/nova.mo is generated.

7. Test nova-scheduler

$ LANGUAGE=ja_JP.UTF-8 ./bin/nova-scheduler --flagfile=./nova-manage.conf

Output messages:

...
DEBUG:root:network_topic : network
WARNING:root:scheduler ノードを開始します
2010-10-27 18:30:41+0900 [-] Log opened.
2010-10-27 18:30:41+0900 [-] twistd 10.0.0 (/usr/bin/python 2.6.5) starting up.
2010-10-27 18:30:41+0900 [-] reactor class: twisted.internet.selectreactor.SelectReactor.
INFO:root:backend <module 'nova.db.sqlalchemy.api' from '/home/iida/openstack/nova-2010.1-i18n/nova/db/sqlalchemy/api.pyc'>
2010-10-27 18:30:41+0900 [-] (root): INFO backend <module 'nova.db.sqlalchemy.api' from '/home/iida/openstack/nova-2010.1-i18n/nova/db/sqlalchemy/api.pyc'>

Migration

• TBD

Test/Demo Plan

• TBD

Unresolved issues

• TBD

BoF agenda and discussion

• TBD