Gringo's Guide to Internationalization.

Transcript

1. A Gringo’s Guide to
   Internationalization
   Going From Green to Experto with Django’s i18n
   Tools.
   Jacob Burch
   @jacobburch
   jacobb
   Tuesday, September 4, 12
   

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2. Me llamo Jacob
   • Engineer at Revolution Systems
   • Architect of CashStar Inc’s i18n efforts
   • 3 Years of C-Grade High School Spanish
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3. Who is Cashstar?
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4. Tuesday, September 4, 12
   

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5. Internationalization
   18 other characters
   i n
   s[1] + str(len(s[1:-1])) + s[-1]
   i18n
   + +
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6. gettext example
   #: constants.py:40
   msgid "Hello"
   msgstr "Hola"
   #: templates/base.html:41 templates/
   login.html:12
   msgid "%(username)s’ Account"
   msgstr "Cuenta de %(username)s"
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7. The Life Cycle of a Po
   File
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8. The Life Cycle of a Po
   File
   • Wrap text in translation function calls
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9. The Life Cycle of a Po
   File
   • Wrap text in translation function calls
   • django-admin.py makemessages
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10. The Life Cycle of a Po
    File
    • Wrap text in translation function calls
    • django-admin.py makemessages
    • Deliver po file to translation service
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11. The Life Cycle of a Po
    File
    • Wrap text in translation function calls
    • django-admin.py makemessages
    • Deliver po file to translation service
    • Receive file back
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12. The Life Cycle of a Po
    File
    • Wrap text in translation function calls
    • django-admin.py makemessages
    • Deliver po file to translation service
    • Receive file back
    • django-admin.py compilemessages
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13. The Life Cycle of a Po
    File
    • Wrap text in translation function calls
    • django-admin.py makemessages
    • Deliver po file to translation service
    • Receive file back
    • django-admin.py compilemessages
    • Fin
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14. Batteries Included
    •LocaleMiddleware
    •Template tags and python methods
    •manage.py makemessages
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15. gettext vs
    gettext_lazy
    >>> lazy_string = gettext_lazy("Hello")
    >>> normal_string = gettext("Hello")
    >>> print repr(lazy_string) #
    >>> print repr(normal-string) # "'Hello'"
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16. gettext best practices
    • Almost always use gettext_lazy
    • If you see a
    in HTML or debug code, You’re trying to use a
    gettext_lazy proxy string too soon.
    • Import gettext or gettext_lazy as _
    • If you need both in the same file, use _ and
    _lazy
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17. template tags
    • trans
    for short phrases with no variables
    • {% trans “Hello there!” %}
    • blocktrans
    for longer phrases containing
    variables
    • blocktrans
    for phrases containing variables
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18. using template tags
    • When possible, use trans
    • Avoid complicated blocktrans signatures
    • With blocktrans: whitespace matters. Keep it limited.
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19. {% blocktrans user=post.comments.recent.user
    user_post_count=post.comments.recent.user.post
    s.count %}
    {{ user }} has {{ user_post count }} posts
    {% endblocktrans %}
    BAD
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20. {% with user=post.comments.recent.user %}
    {% blocktrans user_post_count=user.posts.count %}
    {{ user }} has {{ user_post_count }} posts!
    {% endblocktrans %}
    OK
    {% blocktrans user_post_count=user.posts.count %}
    {{ user }} has {{ user_post_count }} posts!{%
    endblocktrans %}
    GOOD
    {% blocktrans %} {{ user }} has
    {{ user_post_count }} posts!{% endblocktrans %}
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21. The Second, Sad Life Of a .po file
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22. The Second, Sad Life Of a .po file
    • Get told by an non-English speaker that certain words
    aren’t translated
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23. The Second, Sad Life Of a .po file
    • Get told by an non-English speaker that certain words
    aren’t translated
    • Wrap missing text in translation function calls
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24. The Second, Sad Life Of a .po file
    • Get told by an non-English speaker that certain words
    aren’t translated
    • Wrap missing text in translation function calls
    • django-admin.py makemessages
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25. The Second, Sad Life Of a .po file
    • Get told by an non-English speaker that certain words
    aren’t translated
    • Wrap missing text in translation function calls
    • django-admin.py makemessages
    • Dig through translation to find the new ones
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26. The Second, Sad Life Of a .po file
    • Get told by an non-English speaker that certain words
    aren’t translated
    • Wrap missing text in translation function calls
    • django-admin.py makemessages
    • Dig through translation to find the new ones
    • Deliver po file to translation service
    Tuesday, September 4, 12
    

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27. The Second, Sad Life Of a .po file
    • Get told by an non-English speaker that certain words
    aren’t translated
    • Wrap missing text in translation function calls
    • django-admin.py makemessages
    • Dig through translation to find the new ones
    • Deliver po file to translation service
    • Receive file back, re-compile
    Tuesday, September 4, 12
    

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28. The Second, Sad Life Of a .po file
    • Get told by an non-English speaker that certain words
    aren’t translated
    • Wrap missing text in translation function calls
    • django-admin.py makemessages
    • Dig through translation to find the new ones
    • Deliver po file to translation service
    • Receive file back, re-compile
    • Have marketing ask you to change “just two words” in old translation
    Tuesday, September 4, 12
    

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29. The Second, Sad Life Of a .po file
    • Get told by an non-English speaker that certain words
    aren’t translated
    • Wrap missing text in translation function calls
    • django-admin.py makemessages
    • Dig through translation to find the new ones
    • Deliver po file to translation service
    • Receive file back, re-compile
    • Have marketing ask you to change “just two words” in old translation
    • Find out those words are located in the database
    Tuesday, September 4, 12
    

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30. The Second, Sad Life Of a .po file
    • Get told by an non-English speaker that certain words
    aren’t translated
    • Wrap missing text in translation function calls
    • django-admin.py makemessages
    • Dig through translation to find the new ones
    • Deliver po file to translation service
    • Receive file back, re-compile
    • Have marketing ask you to change “just two words” in old translation
    • Find out those words are located in the database
    • With great sadness, manually add those two words into the django.po file
    Tuesday, September 4, 12
    

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31. The Second, Sad Life Of a .po file
    • Get told by an non-English speaker that certain words
    aren’t translated
    • Wrap missing text in translation function calls
    • django-admin.py makemessages
    • Dig through translation to find the new ones
    • Deliver po file to translation service
    • Receive file back, re-compile
    • Have marketing ask you to change “just two words” in old translation
    • Find out those words are located in the database
    • With great sadness, manually add those two words into the django.po file
    • Get told by an non-English speaker that certain words aren’t translated
    Tuesday, September 4, 12
    

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32. The Second, Sad Life Of a .po file
    • Get told by an non-English speaker that certain words
    aren’t translated
    • Wrap missing text in translation function calls
    • django-admin.py makemessages
    • Dig through translation to find the new ones
    • Deliver po file to translation service
    • Receive file back, re-compile
    • Have marketing ask you to change “just two words” in old translation
    • Find out those words are located in the database
    • With great sadness, manually add those two words into the django.po file
    • Get told by an non-English speaker that certain words aren’t translated
    Tuesday, September 4, 12
    

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33. The Second, Sad Life Of a .po file
    • Get told by an non-English speaker that certain words
    aren’t translated
    • Wrap missing text in translation function calls
    • django-admin.py makemessages
    • Dig through translation to find the new ones
    • Deliver po file to translation service
    • Receive file back, re-compile
    • Have marketing ask you to change “just two words” in old translation
    • Find out those words are located in the database
    • With great sadness, manually add those two words into the django.po file
    • Get told by an non-English speaker that certain words aren’t translated
    Tuesday, September 4, 12
    

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34. poxx
    • poxx.py location/of/locale/django.po
    • Munges Translation to easily tell what’s
    been translated (and what hasn’t)
    • “your photo” becomes “ẏǿŭř ƥħǿŧǿ”
    speaker project plug time!
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35. poxx and ‘canonical’ translations
    • poxx.py location/of/locale/django.po -c location/of/locale/canon.po
    • Munges all translations not found in canon.po
    • poxx.py location/of/locale/django.po -c location/of/locale/canon.po --diff
    • Creates location/of/locale/django_diff.po file,
    containing all translations not found in canon.po
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36. django-dbgettext
    •python manage.py dbgettext_export
    • Creates new .po files containing text
    found in db in pre-defined model+fields
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37. Let’s Dive In Deeper
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38. LocaleMiddleware
    • The main engine behind translation.
    • Very “simple”: figures out which language to
    use, activates that language, and sets the
    appropriate request variables.
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39. LocaleMiddleware
    • Language is determined by:
    • URL Path (new in 1.4)
    , then
    • Session code, then
    • User’s cookie, then
    • Accept-Language header, then finally
    • Your project’s LANGUAGE_CODE setting
    django.utils.translation.trans_real.get_language_from_request
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40. • django.utils.translation.trans_real And You
    • DjangoTranslation
    • Utility functions:
    • to_language (en-us) and to_locale (en_US)
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41. Advanced i18n: Multi-Tenancy
    class SiteSpecificLocaleMiddleware(LocaleMiddleware):
    """
    Replaces LocaleMiddleware.
    Only use i18n infrastructure if our site is in settings.TRANSLATED_SITES
    request.site.url is set in an earlier middleware
    """
    def process_request(self, request):
    site_url = request.site.url
    if site_url in settings.TRANSLATED_SITES:
    super(SiteSpecificLocaleMiddleware, self).process_request(request)
    else:
    request.LANGUAGE_CODE = settings.LANGUAGE_CODE
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42. Advanced i18n: Site-specific translations
    class SiteSpecificLocaleMiddleware(LocaleMiddleware):
    """
    Replaces LocaleMiddleware.
    Only use i18n infrastructure if our site is in settings.TRANSLATED_SITES
    request.site.url is set in an earlier middleware
    """
    def process_request(self, request):
    site_url = request.site.url
    site_locale = os.path.join(SOME_PO_FILE_PATH, site_url)
    if os.path.isdir(site_specific_locale):
    site_specific_trans = _translation(
    site_specific_locale,
    request.LANGUAGE_CODE)
    if brand_specific_trans:
    curr_trans = getattr(_active, 'value', None)
    if curr_trans:
    curr_trans.merge(site_specific_trans)
    else:
    curr_trans = site_specific_trans
    _active.value = curr_trans
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43. Why Django i18n isn’t as
    pleasant as it could be
    and perhaps we could
    think of improvements
    “sucks” sounds so mean!
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44. The Future of i18n
    • USE_I18N?
    • Ability to add other non-gettext
    backends
    • Handling of dynamic translations
    • All contained within ticket #14974
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45. Questions?
    • https://github.com/jacobb/django_i18n_examples
    • https://github.com/jacobb/poxx
    • https://bitbucket.org/drmeers/django-dbgettext
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