From 67e6e0fcf35d93f88bfb1a4cbf5c6008d99dd923 Mon Sep 17 00:00:00 2001 From: Aymeric Augustin Date: Sat, 22 Oct 2011 17:17:57 +0000 Subject: [PATCH] Fixed #17087 -- Re-organized the i18n docs to reduce confusion between USE_I18N/USE_L10N and the concepts of internationalization/localisation. Re moved some duplicate content. git-svn-id: http://code.djangoproject.com/svn/django/trunk@17026 bcc190cf-cafb-0310-a4f2-bffc1f526a37 --- docs/howto/i18n.txt | 121 ---- docs/howto/index.txt | 1 - docs/internals/contributing/index.txt | 2 +- .../{translations.txt => localizing.txt} | 22 +- docs/ref/contrib/localflavor.txt | 2 +- docs/ref/settings.txt | 16 +- docs/ref/utils.txt | 2 +- docs/topics/cache.txt | 9 +- docs/topics/i18n/deployment.txt | 217 ------ docs/topics/i18n/formatting.txt | 182 +++++ docs/topics/i18n/index.txt | 108 ++- docs/topics/i18n/localization.txt | 409 ------------ ...ternationalization.txt => translation.txt} | 632 ++++++++++++++++-- 13 files changed, 846 insertions(+), 877 deletions(-) delete mode 100644 docs/howto/i18n.txt rename docs/internals/contributing/{translations.txt => localizing.txt} (84%) delete mode 100644 docs/topics/i18n/deployment.txt create mode 100644 docs/topics/i18n/formatting.txt delete mode 100644 docs/topics/i18n/localization.txt rename docs/topics/i18n/{internationalization.txt => translation.txt} (56%) diff --git a/docs/howto/i18n.txt b/docs/howto/i18n.txt deleted file mode 100644 index 7310e52591..0000000000 --- a/docs/howto/i18n.txt +++ /dev/null @@ -1,121 +0,0 @@ -.. _using-translations-in-your-own-projects: - -=============================================== -Using internationalization in your own projects -=============================================== - -At runtime, Django builds an in-memory unified catalog of literals-translations. -To achieve this it looks for translations by following this algorithm regarding -the order in which it examines the different file paths to load the compiled -:term:`message files ` (``.mo``) and the precedence of multiple -translations for the same literal: - -1. The directories listed in :setting:`LOCALE_PATHS` have the highest - precedence, with the ones appearing first having higher precedence than - the ones appearing later. -2. Then, it looks for and uses if it exists a ``locale`` directory in each - of the installed apps listed in :setting:`INSTALLED_APPS`. The ones - appearing first have higher precedence than the ones appearing later. -3. Then, it looks for a ``locale`` directory in the project directory, or - more accurately, in the directory containing your settings file. -4. Finally, the Django-provided base translation in ``django/conf/locale`` - is used as a fallback. - -.. deprecated:: 1.3 - Lookup in the ``locale`` subdirectory of the directory containing your - settings file (item 3 above) is deprecated since the 1.3 release and will be - removed in Django 1.5. You can use the :setting:`LOCALE_PATHS` setting - instead, by listing the absolute filesystem path of such ``locale`` - directory in the setting value. - -.. seealso:: - - The translations for literals included in JavaScript assets are looked up - following a similar but not identical algorithm. See the - :ref:`javascript_catalog view documentation ` for - more details. - -In all cases the name of the directory containing the translation is expected to -be named using :term:`locale name` notation. E.g. ``de``, ``pt_BR``, ``es_AR``, -etc. - -This way, you can write applications that include their own translations, and -you can override base translations in your project path. Or, you can just build -a big project out of several apps and put all translations into one big common -message file specific to the project you are composing. The choice is yours. - -.. note:: - - If you're using manually configured settings, as described in - :ref:`settings-without-django-settings-module`, the ``locale`` directory in - the project directory will not be examined, since Django loses the ability - to work out the location of the project directory. (Django normally uses the - location of the settings file to determine this, and a settings file doesn't - exist if you're manually configuring your settings.) - -All message file repositories are structured the same way. They are: - -* All paths listed in :setting:`LOCALE_PATHS` in your settings file are - searched for ``/LC_MESSAGES/django.(po|mo)`` -* ``$PROJECTPATH/locale//LC_MESSAGES/django.(po|mo)`` -- - deprecated, see above. -* ``$APPPATH/locale//LC_MESSAGES/django.(po|mo)`` -* ``$PYTHONPATH/django/conf/locale//LC_MESSAGES/django.(po|mo)`` - -To create message files, you use the :djadmin:`django-admin.py makemessages ` -tool. You only need to be in the same directory where the ``locale/`` directory -is located. And you use :djadmin:`django-admin.py compilemessages ` -to produce the binary ``.mo`` files that are used by ``gettext``. Read the -:doc:`/topics/i18n/localization` document for more details. - -You can also run ``django-admin.py compilemessages --settings=path.to.settings`` -to make the compiler process all the directories in your :setting:`LOCALE_PATHS` -setting. - -Finally, you should give some thought to the structure of your translation -files. If your applications need to be delivered to other users and will -be used in other projects, you might want to use app-specific translations. -But using app-specific translations and project-specific translations could -produce weird problems with ``makemessages``: It will traverse all directories -below the current path and so might put message IDs into a unified, common -message file for the current project that are already in application message -files. - -The easiest way out is to store applications that are not part of the project -(and so carry their own translations) outside the project tree. That way, -``django-admin.py makemessages``, when ran on a project level will only extract -strings that are connected to your explicit project and not strings that are -distributed independently. - -Using translations outside views and templates -============================================== - -While Django provides a rich set of i18n tools for use in views and templates, -it does not restrict the usage to Django-specific code. The Django translation -mechanisms can be used to translate arbitrary texts to any language that is -supported by Django (as long as an appropriate translation catalog exists, of -course). You can load a translation catalog, activate it and translate text to -language of your choice, but remember to switch back to original language, as -activating a translation catalog is done on per-thread basis and such change -will affect code running in the same thread. - -For example:: - - from django.utils import translation - def welcome_translated(language): - cur_language = translation.get_language() - try: - translation.activate(language) - text = translation.ugettext('welcome') - finally: - translation.activate(cur_language) - return text - -Calling this function with the value 'de' will give you ``"Willkommen"``, -regardless of :setting:`LANGUAGE_CODE` and language set by middleware. - -Functions of particular interest are ``django.utils.translation.get_language()`` -which returns the language used in the current thread, -``django.utils.translation.activate()`` which activates a translation catalog -for the current thread, and ``django.utils.translation.check_for_language()`` -which checks if the given language is supported by Django. diff --git a/docs/howto/index.txt b/docs/howto/index.txt index 49d0644034..3616f7ae16 100644 --- a/docs/howto/index.txt +++ b/docs/howto/index.txt @@ -18,7 +18,6 @@ you quickly accomplish common tasks. deployment/index error-reporting initial-data - i18n jython legacy-databases outputting-csv diff --git a/docs/internals/contributing/index.txt b/docs/internals/contributing/index.txt index 77af3d611c..7e6de0d491 100644 --- a/docs/internals/contributing/index.txt +++ b/docs/internals/contributing/index.txt @@ -56,7 +56,7 @@ Browse the following sections to find out how: triaging-tickets writing-code/index writing-documentation - translations + localizing committing-code .. _django-users: http://groups.google.com/group/django-users diff --git a/docs/internals/contributing/translations.txt b/docs/internals/contributing/localizing.txt similarity index 84% rename from docs/internals/contributing/translations.txt rename to docs/internals/contributing/localizing.txt index 343839540f..90a07c1e2d 100644 --- a/docs/internals/contributing/translations.txt +++ b/docs/internals/contributing/localizing.txt @@ -1,15 +1,15 @@ -======================================= -Submitting and maintaining translations -======================================= +================= +Localizing Django +================= Various parts of Django, such as the admin site and validation error messages, -are internationalized. This means they display different text depending on each -user's language setting. For this, Django uses the same internationalization and -localization infrastructure available to Django applications, described in the -:doc:`i18n documentation`. +are internationalized. This means they display differently depending on each +user's language or country. For this, Django uses the same internationalization +and localization infrastructure available to Django applications, described in +the :doc:`i18n documentation `. -Internationalization --------------------- +Translations +------------ Translations are contributed by Django users worldwide. The translation work is coordinated at `Transifex`_. @@ -45,8 +45,8 @@ do: For more information about how to use Transifex, read the `Transifex User Guide`_. -Localization ------------- +Formats +------- You can also review ``conf/locale//formats.py``. This file describes the date, time and numbers formatting particularities of your locale. See diff --git a/docs/ref/contrib/localflavor.txt b/docs/ref/contrib/localflavor.txt index 0a39c31b7a..4671906fa1 100644 --- a/docs/ref/contrib/localflavor.txt +++ b/docs/ref/contrib/localflavor.txt @@ -146,7 +146,7 @@ Django's general catalog in ``django/conf/locale``. If you want localflavor's texts to be translated, like form fields error messages, you must include :mod:`django.contrib.localflavor` in the :setting:`INSTALLED_APPS` setting, so the internationalization system can find the catalog, as explained in -:ref:`using-translations-in-your-own-projects`. +:ref:`how-django-discovers-translations`. Adding flavors ============== diff --git a/docs/ref/settings.txt b/docs/ref/settings.txt index c3539192f3..999e2bad00 100644 --- a/docs/ref/settings.txt +++ b/docs/ref/settings.txt @@ -1243,7 +1243,7 @@ LOCALE_PATHS Default: ``()`` (Empty tuple) A tuple of directories where Django looks for translation files. -See :ref:`using-translations-in-your-own-projects`. +See :ref:`how-django-discovers-translations`. Example:: @@ -2038,10 +2038,10 @@ USE_I18N Default: ``True`` -A boolean that specifies whether Django's internationalization system should be -enabled. This provides an easy way to turn it off, for performance. If this is -set to ``False``, Django will make some optimizations so as not to load the -internationalization machinery. +A boolean that specifies whether Django's translation system should be enabled. +This provides an easy way to turn it off, for performance. If this is set to +``False``, Django will make some optimizations so as not to load the +translation machinery. See also :setting:`USE_L10N` @@ -2054,9 +2054,9 @@ USE_L10N Default: ``False`` -A boolean that specifies if data will be localized by default or not. If this -is set to ``True``, e.g. Django will display numbers and dates using the -format of the current locale. +A boolean that specifies if localized formatting of data will be enabled by +default or not. If this is set to ``True``, e.g. Django will display numbers and +dates using the format of the current locale. See also :setting:`USE_I18N` and :setting:`LANGUAGE_CODE` diff --git a/docs/ref/utils.txt b/docs/ref/utils.txt index e4648bd1b9..bce2f59cd3 100644 --- a/docs/ref/utils.txt +++ b/docs/ref/utils.txt @@ -455,7 +455,7 @@ appropriate entities. :synopsis: Internationalization support. For a complete discussion on the usage of the following see the -:doc:`Internationalization documentation `. +:doc:`translation documentation `. .. function:: gettext(message) diff --git a/docs/topics/cache.txt b/docs/topics/cache.txt index 768bd245b8..1d85683d95 100644 --- a/docs/topics/cache.txt +++ b/docs/topics/cache.txt @@ -494,12 +494,9 @@ more on these decorators. .. versionadded:: 1.2 If :setting:`USE_I18N` is set to ``True`` then the generated cache key will -include the name of the active :term:`language`. -This allows you to easily cache multilingual sites without having to create -the cache key yourself. - -See :doc:`/topics/i18n/deployment` for more on how Django discovers the active -language. +include the name of the active :term:`language` -- see also +:ref:`how-django-discovers-language-preference`). This allows you to easily +cache multilingual sites without having to create the cache key yourself. __ `Controlling cache: Using other headers`_ diff --git a/docs/topics/i18n/deployment.txt b/docs/topics/i18n/deployment.txt deleted file mode 100644 index eed5c96af7..0000000000 --- a/docs/topics/i18n/deployment.txt +++ /dev/null @@ -1,217 +0,0 @@ -========================== -Deployment of translations -========================== - -If you don't need internationalization -====================================== - -Django's internationalization hooks are on by default, and that means there's a -bit of i18n-related overhead in certain places of the framework. If you don't -use internationalization, you should take the two seconds to set -:setting:`USE_I18N = False ` in your settings file. If -:setting:`USE_I18N` is set to ``False``, then Django will make some -optimizations so as not to load the internationalization machinery. - -You'll probably also want to remove ``'django.core.context_processors.i18n'`` -from your :setting:`TEMPLATE_CONTEXT_PROCESSORS` setting. - -.. note:: - - There is also an independent but related :setting:`USE_L10N` setting that - controls if Django should implement format localization. - - If :setting:`USE_L10N` is set to ``True``, Django will handle numbers times, - and dates in the format of the current locale. That includes representation - of these field types on templates and allowed input formats for dates, - times on model forms. - - See :ref:`format-localization` for more details. - -If you do need internationalization -=================================== - -.. _how-django-discovers-language-preference: - -How Django discovers language preference ----------------------------------------- - -Once you've prepared your translations -- or, if you just want to use the -translations that come with Django -- you'll just need to activate translation -for your app. - -Behind the scenes, Django has a very flexible model of deciding which language -should be used -- installation-wide, for a particular user, or both. - -To set an installation-wide language preference, set :setting:`LANGUAGE_CODE`. -Django uses this language as the default translation -- the final attempt if no -other translator finds a translation. - -If all you want to do is run Django with your native language, and a language -file is available for it, all you need to do is set :setting:`LANGUAGE_CODE`. - -If you want to let each individual user specify which language he or she -prefers, use ``LocaleMiddleware``. ``LocaleMiddleware`` enables language -selection based on data from the request. It customizes content for each user. - -To use ``LocaleMiddleware``, add ``'django.middleware.locale.LocaleMiddleware'`` -to your :setting:`MIDDLEWARE_CLASSES` setting. Because middleware order -matters, you should follow these guidelines: - -* Make sure it's one of the first middlewares installed. -* It should come after ``SessionMiddleware``, because ``LocaleMiddleware`` - makes use of session data. And it should come before ``CommonMiddleware`` - because ``CommonMiddleware`` needs an activated language in order - to resolve the requested URL. -* If you use ``CacheMiddleware``, put ``LocaleMiddleware`` after it. - -For example, your :setting:`MIDDLEWARE_CLASSES` might look like this:: - - MIDDLEWARE_CLASSES = ( - 'django.contrib.sessions.middleware.SessionMiddleware', - 'django.middleware.locale.LocaleMiddleware', - 'django.middleware.common.CommonMiddleware', - ) - -(For more on middleware, see the :doc:`middleware documentation -`.) - -``LocaleMiddleware`` tries to determine the user's language preference by -following this algorithm: - -.. versionchanged:: 1.4 - -* First, it looks for the language prefix in the requested URL. This is - only performed when you are using the ``i18n_patterns`` function in your - root URLconf. See :ref:`url-internationalization` for more information - about the language prefix and how to internationalize URL patterns. - -* Failing that, it looks for a ``django_language`` key in the current - user's session. - -* Failing that, it looks for a cookie. - - The name of the cookie used is set by the :setting:`LANGUAGE_COOKIE_NAME` - setting. (The default name is ``django_language``.) - -* Failing that, it looks at the ``Accept-Language`` HTTP header. This - header is sent by your browser and tells the server which language(s) you - prefer, in order by priority. Django tries each language in the header - until it finds one with available translations. - -* Failing that, it uses the global :setting:`LANGUAGE_CODE` setting. - -.. _locale-middleware-notes: - -Notes: - -* In each of these places, the language preference is expected to be in the - standard :term:`language format`, as a string. For example, - Brazilian Portuguese is ``pt-br``. - -* If a base language is available but the sublanguage specified is not, - Django uses the base language. For example, if a user specifies ``de-at`` - (Austrian German) but Django only has ``de`` available, Django uses - ``de``. - -* Only languages listed in the :setting:`LANGUAGES` setting can be selected. - If you want to restrict the language selection to a subset of provided - languages (because your application doesn't provide all those languages), - set :setting:`LANGUAGES` to a list of languages. For example:: - - LANGUAGES = ( - ('de', _('German')), - ('en', _('English')), - ) - - This example restricts languages that are available for automatic - selection to German and English (and any sublanguage, like de-ch or - en-us). - -* If you define a custom :setting:`LANGUAGES` setting, as explained in the - previous bullet, it's OK to mark the languages as translation strings - -- but use a "dummy" ``ugettext()`` function, not the one in - ``django.utils.translation``. You should *never* import - ``django.utils.translation`` from within your settings file, because that - module in itself depends on the settings, and that would cause a circular - import. - - The solution is to use a "dummy" ``ugettext()`` function. Here's a sample - settings file:: - - ugettext = lambda s: s - - LANGUAGES = ( - ('de', ugettext('German')), - ('en', ugettext('English')), - ) - - With this arrangement, ``django-admin.py makemessages`` will still find - and mark these strings for translation, but the translation won't happen - at runtime -- so you'll have to remember to wrap the languages in the - *real* ``ugettext()`` in any code that uses :setting:`LANGUAGES` at - runtime. - -* The ``LocaleMiddleware`` can only select languages for which there is a - Django-provided base translation. If you want to provide translations - for your application that aren't already in the set of translations - in Django's source tree, you'll want to provide at least a basic - one as described in the :ref:`Locale restrictions` - note. - -Once ``LocaleMiddleware`` determines the user's preference, it makes this -preference available as ``request.LANGUAGE_CODE`` for each -:class:`~django.http.HttpRequest`. Feel free to read this value in your view -code. Here's a simple example:: - - def hello_world(request, count): - if request.LANGUAGE_CODE == 'de-at': - return HttpResponse("You prefer to read Austrian German.") - else: - return HttpResponse("You prefer to read another language.") - -Note that, with static (middleware-less) translation, the language is in -``settings.LANGUAGE_CODE``, while with dynamic (middleware) translation, it's -in ``request.LANGUAGE_CODE``. - -.. _settings file: ../settings/ -.. _middleware documentation: ../middleware/ -.. _session: ../sessions/ -.. _request object: ../request_response/#httprequest-objects - -How Django discovers translations ---------------------------------- - -As described in :ref:`using-translations-in-your-own-projects`, Django looks for -translations by following this algorithm regarding the order in which it -examines the different file paths to load the compiled :term:`message files -` (``.mo``) and the precedence of multiple translations for the -same literal: - -1. The directories listed in :setting:`LOCALE_PATHS` have the highest - precedence, with the ones appearing first having higher precedence than - the ones appearing later. -2. Then, it looks for and uses if it exists a ``locale`` directory in each - of the installed apps listed in :setting:`INSTALLED_APPS`. The ones - appearing first have higher precedence than the ones appearing later. -3. Then, it looks for a ``locale`` directory in the project directory, or - more accurately, in the directory containing your settings file. -4. Finally, the Django-provided base translation in ``django/conf/locale`` - is used as a fallback. - -.. deprecated:: 1.3 - Lookup in the ``locale`` subdirectory of the directory containing your - settings file (item 3 above) is deprecated since the 1.3 release and will be - removed in Django 1.5. You can use the :setting:`LOCALE_PATHS` setting - instead, by listing the absolute filesystem path of such ``locale`` - directory in the setting value. - -.. seealso:: - - The translations for literals included in JavaScript assets are looked up - following a similar but not identical algorithm. See the - :ref:`javascript_catalog view documentation ` for - more details. - -In all cases the name of the directory containing the translation is expected to -be named using :term:`locale name` notation. E.g. ``de``, ``pt_BR``, ``es_AR``, -etc. diff --git a/docs/topics/i18n/formatting.txt b/docs/topics/i18n/formatting.txt new file mode 100644 index 0000000000..ffd0bcdd22 --- /dev/null +++ b/docs/topics/i18n/formatting.txt @@ -0,0 +1,182 @@ +=================== +Format localization +=================== + +.. _format-localization: + +.. versionadded:: 1.2 + +Overview +======== + +Django's formatting system is capable to display dates, times and numbers in templates using the format specified for the current :term:`locale `. It also handles localized input in forms. + +When it's enabled, two users accessing the same content may see dates, times and +numbers formatted in different ways, depending on the formats for their current +locale. + +The formatting system is disabled by default. To enable it, it's +necessary to set :setting:`USE_L10N = True ` in your settings file. + +.. note:: + + The default :file:`settings.py` file created by :djadmin:`django-admin.py + startproject ` includes :setting:`USE_L10N = True ` + for convenience. + +.. note:: + + There is also an independent but related :setting:`USE_I18N` setting that + controls if Django should activate translation. See + :doc:`/topics/i18n/translation` for more details. + +Locale aware input in forms +=========================== + +When formatting is enabled, Django can use localized formats when parsing dates, +times and numbers in forms. That means it tries different formats for different +locales when guessing the format used by the user when inputting data on forms. + +.. note:: + Django uses different formats for displaying data to those it uses for + parsing data. Most notably, the formats for parsing dates can't use the + ``%a`` (abbreviated weekday name), ``%A`` (full weekday name), + ``%b`` (abbreviated month name), ``%B`` (full month name), + or ``%p`` (AM/PM). + +To enable a form field to localize input and output data simply use its +``localize`` argument:: + + class CashRegisterForm(forms.Form): + product = forms.CharField() + revenue = forms.DecimalField(max_digits=4, decimal_places=2, localize=True) + +.. _topic-l10n-templates: + +Controlling localization in templates +===================================== + +When you have enabled formatting with :setting:`USE_L10N`, Django +will try to use a locale specific format whenever it outputs a value +in a template. + +However, it may not always be appropriate to use localized values -- +for example, if you're outputting Javascript or XML that is designed +to be machine-readable, you will always want unlocalized values. You +may also want to use localization in selected templates, rather than +using localization everywhere. + +To allow for fine control over the use of localization, Django +provides the ``l10n`` template library that contains the following +tags and filters. + +Template tags +------------- + +.. templatetag:: localize + +localize +~~~~~~~~ + +.. versionadded:: 1.3 + +Enables or disables localization of template variables in the +contained block. + +This tag allows a more fine grained control of localization than +:setting:`USE_L10N`. + +To activate or deactivate localization for a template block, use:: + + {% load l10n %} + + {% localize on %} + {{ value }} + {% endlocalize %} + + {% localize off %} + {{ value }} + {% endlocalize %} + +.. note:: + + The value of :setting:`USE_L10N` isn't respected inside of a + ``{% localize %}`` block. + +See :tfilter:`localize` and :tfilter:`unlocalize` for template filters that will +do the same job on a per-variable basis. + +Template filters +---------------- + +.. templatefilter:: localize + +localize +~~~~~~~~ + +.. versionadded:: 1.3 + +Forces localization of a single value. + +For example:: + + {% load l10n %} + + {{ value|localize }} + +To disable localization on a single value, use :tfilter:`unlocalize`. To control +localization over a large section of a template, use the :ttag:`localize` template +tag. + + +.. templatefilter:: unlocalize + +unlocalize +~~~~~~~~~~ + +.. versionadded:: 1.3 + +Forces a single value to be printed without localization. + +For example:: + + {% load l10n %} + + {{ value|unlocalize }} + +To force localization of a single value, use :tfilter:`localize`. To +control localization over a large section of a template, use the +:ttag:`localize` template tag. + +Creating custom format files +============================ + +Django provides format definitions for many locales, but sometimes you might +want to create your own, because a format files doesn't exist for your locale, +or because you want to overwrite some of the values. + +To use custom formats, specify the path where you'll place format files first. +To do that, just set your :setting:`FORMAT_MODULE_PATH` setting to the package +where format files will exist, for instance:: + + FORMAT_MODULE_PATH = 'mysite.formats' + +Files are not placed directly in this directory, but in a directory named as +the locale, and must be named ``formats.py``. + +To customize the English formats, a structure like this would be needed:: + + mysite/ + formats/ + __init__.py + en/ + __init__.py + formats.py + +where :file:`formats.py` contains custom format definitions. For example:: + + THOUSAND_SEPARATOR = ' ' + +to use a space as a thousand separator, instead of the default for English, +a comma. diff --git a/docs/topics/i18n/index.txt b/docs/topics/i18n/index.txt index e499fecb0f..4e2c9c345c 100644 --- a/docs/topics/i18n/index.txt +++ b/docs/topics/i18n/index.txt @@ -2,64 +2,77 @@ Internationalization and localization ===================================== -Overview -======== - -Django has full support for internationalization of text in code and -templates, and format localization of dates and numbers. Here's how it works. - -Essentially, Django does two things: - -* It allows developers and template authors to specify which parts of - their apps should be translatable. -* It uses these hooks to translate Web apps for particular users according - to their language preferences. - -The complete process can be seen as divided in three stages. It is also possible -to identify an identical number of roles with very well defined responsibilities -associated with each of these tasks (although it's perfectly normal if you -find yourself performing more than one of these roles): - -* For application authors wishing to make sure their Django apps can be - used in different locales: :doc:`/topics/i18n/internationalization`. -* For translators wanting to translate Django apps: :doc:`/topics/i18n/localization`. -* For system administrators/final users setting up internationalized apps or - developers integrating third party apps: :doc:`/topics/i18n/deployment`. - .. toctree:: :hidden: :maxdepth: 1 - internationalization - localization - deployment + translation + formatting -.. _ seealso:: +Overview +======== -For more general information about the topic, see the `GNU gettext documentation`_ -and the `Wikipedia article`_. +The goal of internationalization and localization is to allow a single Web +application to offer its content in languages and formats tailored to the +audience. +Django has full support for :doc:`translation of text +` and :doc:`formatting of dates, times and numbers +`. + +Essentially, Django does two things: + +* It allows developers and template authors to specify which parts of their apps + should be translated or formatted for local languages and cultures. +* It uses these hooks to localize Web apps for particular users according to + their preferences. + +Obviously, translation depends on the target language. Formatting usually +depends on the target country. + +Definitions +=========== + +The words "internationalization" and "localization" often cause confusion; +here's a simplified definition: + +.. glossary:: + + internationalization + Preparing the software for localization. Usually done by developers. + + localization + Writing the translations and local formats. Usually done by translators. + +More details can be found in the `W3C Web Internationalization FAQ`_, the `Wikipedia article`_ or the `GNU gettext documentation`_. + +.. _W3C Web Internationalization FAQ: http://www.w3.org/International/questions/qa-i18n .. _GNU gettext documentation: http://www.gnu.org/software/gettext/manual/gettext.html#Concepts .. _Wikipedia article: http://en.wikipedia.org/wiki/Internationalization_and_localization -Glossary -======== +.. warning:: -First lets define some terms that will help us to handle a common language: + Translation and formatting are controlled by :setting:`USE_I18N` and + :setting:`USE_L10N` settings respectively. However, both features involve + internationalization and localization. The names of the settings are an + unfortunate result of Django's history. + +Here are some other terms that will help us to handle a common language: .. glossary:: locale name A locale name, either a language specification of the form ``ll`` or a combined language and country specification of the form ``ll_CC``. - Examples: ``it``, ``de_AT``, ``es``, ``pt_BR``. Note the underscore in - some of them and the case of the part located to its right. + Examples: ``it``, ``de_AT``, ``es``, ``pt_BR``. The language part is + always is lower case and the country part in upper case. The separator + is an underscore. language code Represents the name of a language. Browsers send the names of the languages they accept in the ``Accept-Language`` HTTP header using this - format. Examples: ``it``, ``de-at``, ``es``, ``pt-br``. Note the ``-`` - separator. + format. Examples: ``it``, ``de-at``, ``es``, ``pt-br``. Both the language + and the country parts are in lower case. The separator is a dash. message file A message file is a plain-text file, representing a single language, @@ -70,21 +83,6 @@ First lets define some terms that will help us to handle a common language: translation string A literal that can be translated. -.. _specialties-of-django-i18n: - -Specialties of Django translation -================================= - -Django's translation machinery uses the standard ``gettext`` module that comes -with Python. If you know ``gettext``, you might note these specialties in the -way Django does translation: - -* The string domain is ``django`` or ``djangojs``. This string domain is - used to differentiate between different programs that store their data - in a common message-file library (usually ``/usr/share/locale/``). The - ``django`` domain is used for python and template translation strings - and is loaded into the global translation catalogs. The ``djangojs`` - domain is only used for JavaScript translation catalogs to make sure - that those are as small as possible. -* Django doesn't use ``xgettext`` alone. It uses Python wrappers around - ``xgettext`` and ``msgfmt``. This is mostly for convenience. + format file + A format file is a Python module that defines the data formats for a given + locale. \ No newline at end of file diff --git a/docs/topics/i18n/localization.txt b/docs/topics/i18n/localization.txt deleted file mode 100644 index 13a970f02f..0000000000 --- a/docs/topics/i18n/localization.txt +++ /dev/null @@ -1,409 +0,0 @@ -============ -Localization -============ - -This document covers three localization-related topics: `Creating language -files`_ , `locale aware date, time and numbers input/output in forms`_, -and `controlling localization in templates`_. - -.. _`Creating language files`: how-to-create-language-files_ -.. _`locale aware date, time and numbers input/output in forms`: format-localization_ -.. _`controlling localization in templates`: topic-l10n-templates_ - -.. seealso:: - - The :doc:`/howto/i18n` document included with the Django HOW-TO documents collection. - -.. _how-to-create-language-files: - -How to create language files -============================ - -Once the string literals of an application have been tagged for later -translation, the translation themselves need to be written (or obtained). Here's -how that works. - -.. _locale-restrictions: - -.. admonition:: Locale restrictions - - Django does not support localizing your application into a locale for which - Django itself has not been translated. In this case, it will ignore your - translation files. If you were to try this and Django supported it, you - would inevitably see a mixture of translated strings (from your application) - and English strings (from Django itself). If you want to support a locale - for your application that is not already part of Django, you'll need to make - at least a minimal translation of the Django core. - - A good starting point is to copy the Django English ``.po`` file and to - translate at least some :term:`translation strings `. - -Message files -------------- - -The first step is to create a :term:`message file` for a new language. A message -file is a plain-text file, representing a single language, that contains all -available translation strings and how they should be represented in the given -language. Message files have a ``.po`` file extension. - -Django comes with a tool, ``django-admin.py makemessages``, that automates the -creation and upkeep of these files. - -.. admonition:: Gettext utilities - - The ``makemessages`` command (and ``compilemessages`` discussed later) use - commands from the GNU gettext toolset: ``xgettext``, ``msgfmt``, - ``msgmerge`` and ``msguniq``. - - .. versionchanged:: 1.2 - - The minimum version of the ``gettext`` utilities supported is 0.15. - -To create or update a message file, run this command:: - - django-admin.py makemessages -l de - -...where ``de`` is the language code for the message file you want to create. -The language code, in this case, is in :term:`locale format`. For -example, it's ``pt_BR`` for Brazilian Portuguese and ``de_AT`` for Austrian -German. - -The script should be run from one of two places: - -* The root directory of your Django project. -* The root directory of your Django app. - -The script runs over your project source tree or your application source tree -and pulls out all strings marked for translation. It creates (or updates) a -message file in the directory ``locale/LANG/LC_MESSAGES``. In the ``de`` -example, the file will be ``locale/de/LC_MESSAGES/django.po``. - -By default ``django-admin.py makemessages`` examines every file that has the -``.html`` or ``.txt`` file extension. In case you want to override that -default, use the ``--extension`` or ``-e`` option to specify the file -extensions to examine:: - - django-admin.py makemessages -l de -e txt - -Separate multiple extensions with commas and/or use ``-e`` or ``--extension`` -multiple times:: - - django-admin.py makemessages -l de -e html,txt -e xml - -When :ref:`creating message files from JavaScript source code -` you need to use the special 'djangojs' -domain, **not** ``-e js``. - -.. admonition:: No gettext? - - If you don't have the ``gettext`` utilities installed, ``django-admin.py - makemessages`` will create empty files. If that's the case, either install - the ``gettext`` utilities or just copy the English message file - (``locale/en/LC_MESSAGES/django.po``) if available and use it as a starting - point; it's just an empty translation file. - -.. admonition:: Working on Windows? - - If you're using Windows and need to install the GNU gettext utilities so - ``django-admin makemessages`` works see :ref:`gettext_on_windows` for more - information. - -The format of ``.po`` files is straightforward. Each ``.po`` file contains a -small bit of metadata, such as the translation maintainer's contact -information, but the bulk of the file is a list of **messages** -- simple -mappings between translation strings and the actual translated text for the -particular language. - -For example, if your Django app contained a translation string for the text -``"Welcome to my site."``, like so:: - - _("Welcome to my site.") - -...then ``django-admin.py makemessages`` will have created a ``.po`` file -containing the following snippet -- a message:: - - #: path/to/python/module.py:23 - msgid "Welcome to my site." - msgstr "" - -A quick explanation: - -* ``msgid`` is the translation string, which appears in the source. Don't - change it. -* ``msgstr`` is where you put the language-specific translation. It starts - out empty, so it's your responsibility to change it. Make sure you keep - the quotes around your translation. -* As a convenience, each message includes, in the form of a comment line - prefixed with ``#`` and located above the ``msgid`` line, the filename and - line number from which the translation string was gleaned. - -Long messages are a special case. There, the first string directly after the -``msgstr`` (or ``msgid``) is an empty string. Then the content itself will be -written over the next few lines as one string per line. Those strings are -directly concatenated. Don't forget trailing spaces within the strings; -otherwise, they'll be tacked together without whitespace! - -.. admonition:: Mind your charset - - When creating a PO file with your favorite text editor, first edit - the charset line (search for ``"CHARSET"``) and set it to the charset - you'll be using to edit the content. Due to the way the ``gettext`` tools - work internally and because we want to allow non-ASCII source strings in - Django's core and your applications, you **must** use UTF-8 as the encoding - for your PO file. This means that everybody will be using the same - encoding, which is important when Django processes the PO files. - -To reexamine all source code and templates for new translation strings and -update all message files for **all** languages, run this:: - - django-admin.py makemessages -a - -Compiling message files ------------------------ - -After you create your message file -- and each time you make changes to it -- -you'll need to compile it into a more efficient form, for use by ``gettext``. -Do this with the ``django-admin.py compilemessages`` utility. - -This tool runs over all available ``.po`` files and creates ``.mo`` files, which -are binary files optimized for use by ``gettext``. In the same directory from -which you ran ``django-admin.py makemessages``, run ``django-admin.py -compilemessages`` like this:: - - django-admin.py compilemessages - -That's it. Your translations are ready for use. - -.. admonition:: Working on Windows? - - If you're using Windows and need to install the GNU gettext utilities so - ``django-admin compilemessages`` works see :ref:`gettext_on_windows` for more - information. - -.. admonition:: .po files: Encoding and BOM usage. - - Django only supports ``.po`` files encoded in UTF-8 and without any BOM - (Byte Order Mark) so if your text editor adds such marks to the beginning of - files by default then you will need to reconfigure it. - -.. _creating-message-files-from-js-code: - -Creating message files from JavaScript source code -================================================== - -You create and update the message files the same way as the other Django -message files -- with the ``django-admin.py makemessages`` tool. The only -difference is you need to explicitly specify what in gettext parlance is known -as a domain in this case the ``djangojs`` domain, by providing a ``-d djangojs`` -parameter, like this:: - - django-admin.py makemessages -d djangojs -l de - -This would create or update the message file for JavaScript for German. -After updating message files, just run ``django-admin.py compilemessages`` -the same way as you do with normal Django message files. - -.. _gettext_on_windows: - -``gettext`` on Windows -====================== - -This is only needed for people who either want to extract message IDs or compile -message files (``.po``). Translation work itself just involves editing existing -files of this type, but if you want to create your own message files, or want to -test or compile a changed message file, you will need the ``gettext`` utilities: - -* Download the following zip files from the GNOME servers - http://ftp.gnome.org/pub/gnome/binaries/win32/dependencies/ or from one - of its mirrors_ - - * ``gettext-runtime-X.zip`` - * ``gettext-tools-X.zip`` - - ``X`` is the version number, we are requiring ``0.15`` or higher. - -* Extract the contents of the ``bin\`` directories in both files to the - same folder on your system (i.e. ``C:\Program Files\gettext-utils``) - -* Update the system PATH: - - * ``Control Panel > System > Advanced > Environment Variables``. - * In the ``System variables`` list, click ``Path``, click ``Edit``. - * Add ``;C:\Program Files\gettext-utils\bin`` at the end of the - ``Variable value`` field. - -.. _mirrors: http://ftp.gnome.org/pub/GNOME/MIRRORS - -You may also use ``gettext`` binaries you have obtained elsewhere, so long as -the ``xgettext --version`` command works properly. Do not attempt to use Django -translation utilities with a ``gettext`` package if the command ``xgettext ---version`` entered at a Windows command prompt causes a popup window saying -"xgettext.exe has generated errors and will be closed by Windows". - -.. _format-localization: - -Format localization -=================== - -.. versionadded:: 1.2 - -Django's formatting system is disabled by default. To enable it, it's -necessary to set :setting:`USE_L10N = True ` in your settings file. - -.. note:: - - The default :file:`settings.py` file created by :djadmin:`django-admin.py - startproject ` includes :setting:`USE_L10N = True ` - for convenience. - -When using Django's formatting system, dates and numbers on templates will be -displayed using the format specified for the current locale. Two users -accessing the same content, but in different language, will see date and -number fields formatted in different ways, depending on the format for their -current locale. - -Django will also use localized formats when parsing data in forms. That means -Django uses different formats for different locales when guessing the format -used by the user when inputting data on forms. - -.. note:: - Django uses different formats for displaying data to those it uses for - parsing data. Most notably, the formats for parsing dates can't use the - ``%a`` (abbreviated weekday name), ``%A`` (full weekday name), - ``%b`` (abbreviated month name), ``%B`` (full month name), - or ``%p`` (AM/PM). - -To enable a form field to localize input and output data simply use its -``localize`` argument:: - - class CashRegisterForm(forms.Form): - product = forms.CharField() - revenue = forms.DecimalField(max_digits=4, decimal_places=2, localize=True) - -Creating custom format files ----------------------------- - -Django provides format definitions for many locales, but sometimes you might -want to create your own, because a format files doesn't exist for your locale, -or because you want to overwrite some of the values. - -To use custom formats, first thing to do, is to specify the path where you'll -place format files. To do that, just set your :setting:`FORMAT_MODULE_PATH` -setting to the path (in the format ``'foo.bar.baz``) where format files -will exists. - -Files are not placed directly in this directory, but in a directory named as -the locale, and must be named ``formats.py``. - -To customize the English formats, a structure like this would be needed:: - - mysite/ - formats/ - __init__.py - en/ - __init__.py - formats.py - -where :file:`formats.py` contains custom format definitions. For example:: - - THOUSAND_SEPARATOR = ' ' - -to use a space as a thousand separator, instead of the default for English, -a comma. - -.. _topic-l10n-templates: - -Controlling localization in templates -===================================== - -When you have enabled localization using :setting:`USE_L10N`, Django -will try to use a locale specific format whenever it outputs a value -in a template. - -However, it may not always be appropriate to use localized values -- -for example, if you're outputting Javascript or XML that is designed -to be machine-readable, you will always want unlocalized values. You -may also want to use localization in selected templates, rather than -using localization everywhere. - -To allow for fine control over the use of localization, Django -provides the ``l10n`` template library that contains the following -tags and filters. - -Template tags -------------- - -.. templatetag:: localize - -localize -~~~~~~~~ - -.. versionadded:: 1.3 - -Enables or disables localization of template variables in the -contained block. - -This tag allows a more fine grained control of localization than -:setting:`USE_L10N`. - -To activate or deactivate localization for a template block, use:: - - {% load l10n %} - - {% localize on %} - {{ value }} - {% endlocalize %} - - {% localize off %} - {{ value }} - {% endlocalize %} - -.. note:: - - The value of :setting:`USE_L10N` is not respected inside of a - `{% localize %}` block. - -See :tfilter:`localized` and :tfilter:`unlocalized` for a template filter that will -do the same job on a per-variable basis. - -Template filters ----------------- - -.. templatefilter:: localize - -localize -~~~~~~~~ - -.. versionadded:: 1.3 - -Forces localization of a single value. - -For example:: - - {% load l10n %} - - {{ value|localize }} - -To disable localization on a single value, use :tfilter:`unlocalize`. To control -localization over a large section of a template, use the :ttag:`localize` template -tag. - - -.. templatefilter:: unlocalize - -unlocalize -~~~~~~~~~~ - -.. versionadded:: 1.3 - -Forces a single value to be printed without localization. - -For example:: - - {% load l10n %} - - {{ value|unlocalize }} - -To force localization of a single value, use :tfilter:`localize`. To -control localization over a large section of a template, use the -:ttag:`localize` template tag. diff --git a/docs/topics/i18n/internationalization.txt b/docs/topics/i18n/translation.txt similarity index 56% rename from docs/topics/i18n/internationalization.txt rename to docs/topics/i18n/translation.txt index c8611acff8..bef052e52d 100644 --- a/docs/topics/i18n/internationalization.txt +++ b/docs/topics/i18n/translation.txt @@ -1,27 +1,44 @@ -==================== -Internationalization -==================== +=========== +Translation +=========== .. module:: django.utils.translation Overview ======== -The goal of internationalization is to allow a single Web application to offer -its content and functionality in multiple languages and locales. +In order to make a Django project translatable, you have to add a minimal amount +of hooks to your Python code and templates. These hooks are called +:term:`translation strings `. They tell Django: "This text +should be translated into the end user's language, if a translation for this +text is available in that language." It's your responsibility to mark +translatable strings; the system can only translate strings it knows about. -For text translations, you, the Django developer, can accomplish this goal by -adding a minimal amount of hooks to your Python and templates. These hooks -are called **translation strings**. They tell Django: "This text should be -translated into the end user's language, if a translation for this text is -available in that language." It's your responsibility to mark translatable -strings; the system can only translate strings it knows about. +Django then provides utilities to extract the translation strings into a +:term:`message file`. This file is a convenient way for translators to provide +the equivalent of the translation strings in the target language. Once the +translators have filled in the message file, it must be compiled. This process +relies on the GNU gettext toolset. -Django takes care of using these hooks to translate Web apps, on the fly, -according to users' language preferences. +Once this is done, Django takes care of translating Web apps on the fly in each +available language, according to users' language preferences. -Specifying translation strings: In Python code -============================================== +Django's internationalization hooks are on by default, and that means there's a +bit of i18n-related overhead in certain places of the framework. If you don't +use internationalization, you should take the two seconds to set +:setting:`USE_I18N = False ` in your settings file. Then Django will +make some optimizations so as not to load the internationalization machinery. +You'll probably also want to remove ``'django.core.context_processors.i18n'`` +from your :setting:`TEMPLATE_CONTEXT_PROCESSORS` setting. + +.. note:: + + There is also an independent but related :setting:`USE_L10N` setting that + controls if Django should implement format localization. See + :doc:`/topics/i18n/formatting` for more details. + +Internationalization: in Python code +==================================== Standard translation -------------------- @@ -85,8 +102,8 @@ Translation works on variables. Again, here's an identical example:: (The caveat with using variables or computed values, as in the previous two examples, is that Django's translation-string-detecting utility, -``django-admin.py makemessages``, won't be able to find these strings. More on -``makemessages`` later.) +:djadmin:`django-admin.py makemessages `, won't be able to find +these strings. More on :djadmin:`makemessages` later.) The strings you pass to ``_()`` or ``ugettext()`` can take placeholders, specified with Python's standard named-string interpolation syntax. Example:: @@ -126,7 +143,7 @@ This also works in templates with the :ttag:`comment` tag: {% comment %}Translators: This is a text of the base template {% endcomment %} -The comment will then appear in the resulting .po file and should also be +The comment will then appear in the resulting ``.po`` file and should also be displayed by most translation tools. Marking strings as no-op @@ -221,9 +238,10 @@ cardinality of the elements at play. count ) % d - You would get a ``a format specification for argument 'name', as in - 'msgstr[0]', doesn't exist in 'msgid'`` error when running - ``django-admin.py compilemessages``. + You would get an error when running :djadmin:`django-admin.py + compilemessages `:: + + a format specification for argument 'name', as in 'msgstr[0]', doesn't exist in 'msgid' .. _contextual-markers: @@ -239,10 +257,10 @@ these words correctly in different contexts, you can use the :func:`django.utils.translation.npgettext()` function if the string needs pluralization. Both take a context string as the first variable. -In the resulting .po file, the string will then appear as often as there are -different contextual markers for the same string (the context will appear on -the ``msgctxt`` line), allowing the translator to give a different translation -for each of them. +In the resulting ``.po`` file, the string will then appear as often as there are +different contextual markers for the same string (the context will appear on the +``msgctxt`` line), allowing the translator to give a different translation for +each of them. For example:: @@ -258,7 +276,7 @@ or:: name = models.CharField(help_text=pgettext_lazy( 'help text for MyThing model', 'This is the help text')) -will appear in the .po file as: +will appear in the ``.po`` file as: .. code-block:: po @@ -333,7 +351,7 @@ name:: class Meta: verbose_name = _('my thing') - verbose_name_plural = _('mythings') + verbose_name_plural = _('my things') Notes on model classes translation ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ @@ -398,7 +416,7 @@ strings when ``result`` itself is used in a string (usually at template rendering time). Localized names of languages -============================ +---------------------------- .. function:: get_language_info @@ -421,8 +439,8 @@ Similar access to this information is available for template code. See below. .. _specifying-translation-strings-in-template-code: -Specifying translation strings: In template code -================================================ +Internationalization: in template code +====================================== .. highlightlang:: html+django @@ -672,8 +690,8 @@ There are also simple filters available for convenience: .. _Django templates: ../templates_python/ -Specifying translation strings: In JavaScript code -================================================== +Internationalization: in JavaScript code +======================================== .. highlightlang:: python @@ -681,8 +699,8 @@ Adding translations to JavaScript poses some problems: * JavaScript code doesn't have access to a ``gettext`` implementation. -* JavaScript code doesn't have access to .po or .mo files; they need to be - delivered by the server. +* JavaScript code doesn't have access to ``.po`` or ``.mo`` files; they need to + be delivered by the server. * The translation catalogs for JavaScript should be kept as small as possible. @@ -700,12 +718,12 @@ The ``javascript_catalog`` view .. function:: javascript_catalog(request, domain='djangojs', packages=None) -The main solution to these problems is the :meth:`django.views.i18n.javascript_catalog` -view, which sends out a JavaScript code library with functions that mimic the -``gettext`` interface, plus an array of translation strings. Those translation -strings are taken from applications or Django core, according to what you -specify in either the info_dict or the URL. Paths listed in -:setting:`LOCALE_PATHS` are also included. +The main solution to these problems is the +:meth:`django.views.i18n.javascript_catalog` view, which sends out a JavaScript +code library with functions that mimic the ``gettext`` interface, plus an array +of translation strings. Those translation strings are taken from applications or +Django core, according to what you specify in either the ``info_dict`` or the +URL. Paths listed in :setting:`LOCALE_PATHS` are also included. You hook it up like this:: @@ -815,8 +833,8 @@ to produce proper pluralizations). .. _url-internationalization: -Specifying translation strings: In URL patterns -=============================================== +Internationalization: in URL patterns +===================================== .. versionadded:: 1.4 @@ -922,9 +940,9 @@ URL patterns can also be marked translatable using the ) -After you've created the translations (see :doc:`localization` for more -information), the :func:`~django.core.urlresolvers.reverse` function will -return the URL in the active language. Example:: +After you've created the translations, the +:func:`~django.core.urlresolvers.reverse` function will return the URL in the +active language. Example:: from django.core.urlresolvers import reverse from django.utils.translation import activate @@ -971,10 +989,242 @@ template tag. It enables the given language in the enclosed template section: The :ttag:`language` tag expects the language code as the only argument. +.. _how-to-create-language-files: + +Localization: how to create language files +========================================== + +Once the string literals of an application have been tagged for later +translation, the translation themselves need to be written (or obtained). Here's +how that works. + +.. _locale-restrictions: + +.. admonition:: Locale restrictions + + Django does not support localizing your application into a locale for which + Django itself has not been translated. In this case, it will ignore your + translation files. If you were to try this and Django supported it, you + would inevitably see a mixture of translated strings (from your application) + and English strings (from Django itself). If you want to support a locale + for your application that is not already part of Django, you'll need to make + at least a minimal translation of the Django core. + + A good starting point is to copy the Django English ``.po`` file and to + translate at least some :term:`translation strings `. + +Message files +------------- + +The first step is to create a :term:`message file` for a new language. A message +file is a plain-text file, representing a single language, that contains all +available translation strings and how they should be represented in the given +language. Message files have a ``.po`` file extension. + +Django comes with a tool, :djadmin:`django-admin.py makemessages +`, that automates the creation and upkeep of these files. + +.. admonition:: Gettext utilities + + The ``makemessages`` command (and ``compilemessages`` discussed later) use + commands from the GNU gettext toolset: ``xgettext``, ``msgfmt``, + ``msgmerge`` and ``msguniq``. + + .. versionchanged:: 1.2 + + The minimum version of the ``gettext`` utilities supported is 0.15. + +To create or update a message file, run this command:: + + django-admin.py makemessages -l de + +...where ``de`` is the language code for the message file you want to create. +The language code, in this case, is in :term:`locale format`. For +example, it's ``pt_BR`` for Brazilian Portuguese and ``de_AT`` for Austrian +German. + +The script should be run from one of two places: + +* The root directory of your Django project. +* The root directory of your Django app. + +The script runs over your project source tree or your application source tree +and pulls out all strings marked for translation. It creates (or updates) a +message file in the directory ``locale/LANG/LC_MESSAGES``. In the ``de`` +example, the file will be ``locale/de/LC_MESSAGES/django.po``. + +By default :djadmin:`django-admin.py makemessages ` examines every +file that has the ``.html`` or ``.txt`` file extension. In case you want to +override that default, use the ``--extension`` or ``-e`` option to specify the +file extensions to examine:: + + django-admin.py makemessages -l de -e txt + +Separate multiple extensions with commas and/or use ``-e`` or ``--extension`` +multiple times:: + + django-admin.py makemessages -l de -e html,txt -e xml + +.. warning:: + + When :ref:`creating message files from JavaScript source code + ` you need to use the special + 'djangojs' domain, **not** ``-e js``. + +.. admonition:: No gettext? + + If you don't have the ``gettext`` utilities installed, + :djadmin:`makemessages` will create empty files. If that's the case, either + install the ``gettext`` utilities or just copy the English message file + (``locale/en/LC_MESSAGES/django.po``) if available and use it as a starting + point; it's just an empty translation file. + +.. admonition:: Working on Windows? + + If you're using Windows and need to install the GNU gettext utilities so + :djadmin:`makemessages` works, see :ref:`gettext_on_windows` for more + information. + +The format of ``.po`` files is straightforward. Each ``.po`` file contains a +small bit of metadata, such as the translation maintainer's contact +information, but the bulk of the file is a list of **messages** -- simple +mappings between translation strings and the actual translated text for the +particular language. + +For example, if your Django app contained a translation string for the text +``"Welcome to my site."``, like so:: + + _("Welcome to my site.") + +...then :djadmin:`django-admin.py makemessages ` will have created +a ``.po`` file containing the following snippet -- a message:: + + #: path/to/python/module.py:23 + msgid "Welcome to my site." + msgstr "" + +A quick explanation: + +* ``msgid`` is the translation string, which appears in the source. Don't + change it. +* ``msgstr`` is where you put the language-specific translation. It starts + out empty, so it's your responsibility to change it. Make sure you keep + the quotes around your translation. +* As a convenience, each message includes, in the form of a comment line + prefixed with ``#`` and located above the ``msgid`` line, the filename and + line number from which the translation string was gleaned. + +Long messages are a special case. There, the first string directly after the +``msgstr`` (or ``msgid``) is an empty string. Then the content itself will be +written over the next few lines as one string per line. Those strings are +directly concatenated. Don't forget trailing spaces within the strings; +otherwise, they'll be tacked together without whitespace! + +.. admonition:: Mind your charset + + When creating a PO file with your favorite text editor, first edit + the charset line (search for ``"CHARSET"``) and set it to the charset + you'll be using to edit the content. Due to the way the ``gettext`` tools + work internally and because we want to allow non-ASCII source strings in + Django's core and your applications, you **must** use UTF-8 as the encoding + for your PO file. This means that everybody will be using the same + encoding, which is important when Django processes the PO files. + +To reexamine all source code and templates for new translation strings and +update all message files for **all** languages, run this:: + + django-admin.py makemessages -a + +Compiling message files +----------------------- + +After you create your message file -- and each time you make changes to it -- +you'll need to compile it into a more efficient form, for use by ``gettext``. Do +this with the :djadmin:`django-admin.py compilemessages ` +utility. + +This tool runs over all available ``.po`` files and creates ``.mo`` files, which +are binary files optimized for use by ``gettext``. In the same directory from +which you ran :djadmin:`django-admin.py makemessages `, run :djadmin:`django-admin.py compilemessages ` like this:: + + django-admin.py compilemessages + +That's it. Your translations are ready for use. + +.. admonition:: Working on Windows? + + If you're using Windows and need to install the GNU gettext utilities so + :djadmin:`django-admin.py compilemessages ` works see + :ref:`gettext_on_windows` for more information. + +.. admonition:: .po files: Encoding and BOM usage. + + Django only supports ``.po`` files encoded in UTF-8 and without any BOM + (Byte Order Mark) so if your text editor adds such marks to the beginning of + files by default then you will need to reconfigure it. + +.. _creating-message-files-from-js-code: + +Creating message files from JavaScript source code +-------------------------------------------------- + +You create and update the message files the same way as the other Django message +files -- with the :djadmin:`django-admin.py makemessages ` tool. +The only difference is you need to explicitly specify what in gettext parlance +is known as a domain in this case the ``djangojs`` domain, by providing a ``-d +djangojs`` parameter, like this:: + + django-admin.py makemessages -d djangojs -l de + +This would create or update the message file for JavaScript for German. After +updating message files, just run :djadmin:`django-admin.py compilemessages +` the same way as you do with normal Django message files. + +.. _gettext_on_windows: + +``gettext`` on Windows +---------------------- + +This is only needed for people who either want to extract message IDs or compile +message files (``.po``). Translation work itself just involves editing existing +files of this type, but if you want to create your own message files, or want to +test or compile a changed message file, you will need the ``gettext`` utilities: + +* Download the following zip files from the GNOME servers + http://ftp.gnome.org/pub/gnome/binaries/win32/dependencies/ or from one + of its mirrors_ + + * ``gettext-runtime-X.zip`` + * ``gettext-tools-X.zip`` + + ``X`` is the version number, we are requiring ``0.15`` or higher. + +* Extract the contents of the ``bin\`` directories in both files to the + same folder on your system (i.e. ``C:\Program Files\gettext-utils``) + +* Update the system PATH: + + * ``Control Panel > System > Advanced > Environment Variables``. + * In the ``System variables`` list, click ``Path``, click ``Edit``. + * Add ``;C:\Program Files\gettext-utils\bin`` at the end of the + ``Variable value`` field. + +.. _mirrors: http://ftp.gnome.org/pub/GNOME/MIRRORS + +You may also use ``gettext`` binaries you have obtained elsewhere, so long as +the ``xgettext --version`` command works properly. Do not attempt to use Django +translation utilities with a ``gettext`` package if the command ``xgettext +--version`` entered at a Windows command prompt causes a popup window saying +"xgettext.exe has generated errors and will be closed by Windows". + + +Miscellaneous +============= + .. _set_language-redirect-view: The ``set_language`` redirect view -================================== +---------------------------------- .. highlightlang:: python @@ -1019,3 +1269,293 @@ Here's example HTML template code: + +Using translations outside views and templates +---------------------------------------------- + +While Django provides a rich set of i18n tools for use in views and templates, +it does not restrict the usage to Django-specific code. The Django translation +mechanisms can be used to translate arbitrary texts to any language that is +supported by Django (as long as an appropriate translation catalog exists, of +course). You can load a translation catalog, activate it and translate text to +language of your choice, but remember to switch back to original language, as +activating a translation catalog is done on per-thread basis and such change +will affect code running in the same thread. + +For example:: + + from django.utils import translation + def welcome_translated(language): + cur_language = translation.get_language() + try: + translation.activate(language) + text = translation.ugettext('welcome') + finally: + translation.activate(cur_language) + return text + +Calling this function with the value 'de' will give you ``"Willkommen"``, +regardless of :setting:`LANGUAGE_CODE` and language set by middleware. + +Functions of particular interest are ``django.utils.translation.get_language()`` +which returns the language used in the current thread, +``django.utils.translation.activate()`` which activates a translation catalog +for the current thread, and ``django.utils.translation.check_for_language()`` +which checks if the given language is supported by Django. + +Implementation notes +==================== + +.. _specialties-of-django-i18n: + +Specialties of Django translation +--------------------------------- + +Django's translation machinery uses the standard ``gettext`` module that comes +with Python. If you know ``gettext``, you might note these specialties in the +way Django does translation: + +* The string domain is ``django`` or ``djangojs``. This string domain is + used to differentiate between different programs that store their data + in a common message-file library (usually ``/usr/share/locale/``). The + ``django`` domain is used for python and template translation strings + and is loaded into the global translation catalogs. The ``djangojs`` + domain is only used for JavaScript translation catalogs to make sure + that those are as small as possible. +* Django doesn't use ``xgettext`` alone. It uses Python wrappers around + ``xgettext`` and ``msgfmt``. This is mostly for convenience. + +.. _how-django-discovers-language-preference: + +How Django discovers language preference +---------------------------------------- + +Once you've prepared your translations -- or, if you just want to use the +translations that come with Django -- you'll just need to activate translation +for your app. + +Behind the scenes, Django has a very flexible model of deciding which language +should be used -- installation-wide, for a particular user, or both. + +To set an installation-wide language preference, set :setting:`LANGUAGE_CODE`. +Django uses this language as the default translation -- the final attempt if no +other translator finds a translation. + +If all you want to do is run Django with your native language, and a language +file is available for it, all you need to do is set :setting:`LANGUAGE_CODE`. + +If you want to let each individual user specify which language he or she +prefers, use ``LocaleMiddleware``. ``LocaleMiddleware`` enables language +selection based on data from the request. It customizes content for each user. + +To use ``LocaleMiddleware``, add ``'django.middleware.locale.LocaleMiddleware'`` +to your :setting:`MIDDLEWARE_CLASSES` setting. Because middleware order +matters, you should follow these guidelines: + +* Make sure it's one of the first middlewares installed. +* It should come after ``SessionMiddleware``, because ``LocaleMiddleware`` + makes use of session data. And it should come before ``CommonMiddleware`` + because ``CommonMiddleware`` needs an activated language in order + to resolve the requested URL. +* If you use ``CacheMiddleware``, put ``LocaleMiddleware`` after it. + +For example, your :setting:`MIDDLEWARE_CLASSES` might look like this:: + + MIDDLEWARE_CLASSES = ( + 'django.contrib.sessions.middleware.SessionMiddleware', + 'django.middleware.locale.LocaleMiddleware', + 'django.middleware.common.CommonMiddleware', + ) + +(For more on middleware, see the :doc:`middleware documentation +`.) + +``LocaleMiddleware`` tries to determine the user's language preference by +following this algorithm: + +.. versionchanged:: 1.4 + +* First, it looks for the language prefix in the requested URL. This is + only performed when you are using the ``i18n_patterns`` function in your + root URLconf. See :ref:`url-internationalization` for more information + about the language prefix and how to internationalize URL patterns. + +* Failing that, it looks for a ``django_language`` key in the current + user's session. + +* Failing that, it looks for a cookie. + + The name of the cookie used is set by the :setting:`LANGUAGE_COOKIE_NAME` + setting. (The default name is ``django_language``.) + +* Failing that, it looks at the ``Accept-Language`` HTTP header. This + header is sent by your browser and tells the server which language(s) you + prefer, in order by priority. Django tries each language in the header + until it finds one with available translations. + +* Failing that, it uses the global :setting:`LANGUAGE_CODE` setting. + +.. _locale-middleware-notes: + +Notes: + +* In each of these places, the language preference is expected to be in the + standard :term:`language format`, as a string. For example, + Brazilian Portuguese is ``pt-br``. + +* If a base language is available but the sublanguage specified is not, + Django uses the base language. For example, if a user specifies ``de-at`` + (Austrian German) but Django only has ``de`` available, Django uses + ``de``. + +* Only languages listed in the :setting:`LANGUAGES` setting can be selected. + If you want to restrict the language selection to a subset of provided + languages (because your application doesn't provide all those languages), + set :setting:`LANGUAGES` to a list of languages. For example:: + + LANGUAGES = ( + ('de', _('German')), + ('en', _('English')), + ) + + This example restricts languages that are available for automatic + selection to German and English (and any sublanguage, like de-ch or + en-us). + +* If you define a custom :setting:`LANGUAGES` setting, as explained in the + previous bullet, it's OK to mark the languages as translation strings + -- but use a "dummy" ``ugettext()`` function, not the one in + ``django.utils.translation``. You should *never* import + ``django.utils.translation`` from within your settings file, because that + module in itself depends on the settings, and that would cause a circular + import. + + The solution is to use a "dummy" ``ugettext()`` function. Here's a sample + settings file:: + + ugettext = lambda s: s + + LANGUAGES = ( + ('de', ugettext('German')), + ('en', ugettext('English')), + ) + + With this arrangement, :djadmin:`django-admin.py makemessages ` + will still find and mark these strings for translation, but the translation + won't happen at runtime -- so you'll have to remember to wrap the languages in + the *real* ``ugettext()`` in any code that uses :setting:`LANGUAGES` at + runtime. + +* The ``LocaleMiddleware`` can only select languages for which there is a + Django-provided base translation. If you want to provide translations + for your application that aren't already in the set of translations + in Django's source tree, you'll want to provide at least a basic + one as described in the :ref:`Locale restrictions` + note. + +Once ``LocaleMiddleware`` determines the user's preference, it makes this +preference available as ``request.LANGUAGE_CODE`` for each +:class:`~django.http.HttpRequest`. Feel free to read this value in your view +code. Here's a simple example:: + + def hello_world(request, count): + if request.LANGUAGE_CODE == 'de-at': + return HttpResponse("You prefer to read Austrian German.") + else: + return HttpResponse("You prefer to read another language.") + +Note that, with static (middleware-less) translation, the language is in +``settings.LANGUAGE_CODE``, while with dynamic (middleware) translation, it's +in ``request.LANGUAGE_CODE``. + +.. _settings file: ../settings/ +.. _middleware documentation: ../middleware/ +.. _session: ../sessions/ +.. _request object: ../request_response/#httprequest-objects + +.. _how-django-discovers-translations: + +How Django discovers translations +--------------------------------- + +At runtime, Django builds an in-memory unified catalog of literals-translations. +To achieve this it looks for translations by following this algorithm regarding +the order in which it examines the different file paths to load the compiled +:term:`message files ` (``.mo``) and the precedence of multiple +translations for the same literal: + +1. The directories listed in :setting:`LOCALE_PATHS` have the highest + precedence, with the ones appearing first having higher precedence than + the ones appearing later. +2. Then, it looks for and uses if it exists a ``locale`` directory in each + of the installed apps listed in :setting:`INSTALLED_APPS`. The ones + appearing first have higher precedence than the ones appearing later. +3. Then, it looks for a ``locale`` directory in the project directory, or + more accurately, in the directory containing your settings file. +4. Finally, the Django-provided base translation in ``django/conf/locale`` + is used as a fallback. + +.. deprecated:: 1.3 + + Lookup in the ``locale`` subdirectory of the directory containing your + settings file (item 3 above) is deprecated since the 1.3 release and will be + removed in Django 1.5. You can use the :setting:`LOCALE_PATHS` setting + instead, by listing the absolute filesystem path of such ``locale`` + directory in the setting value. + +.. seealso:: + + The translations for literals included in JavaScript assets are looked up + following a similar but not identical algorithm. See the + :ref:`javascript_catalog view documentation ` for + more details. + +In all cases the name of the directory containing the translation is expected to +be named using :term:`locale name` notation. E.g. ``de``, ``pt_BR``, ``es_AR``, +etc. + +This way, you can write applications that include their own translations, and +you can override base translations in your project path. Or, you can just build +a big project out of several apps and put all translations into one big common +message file specific to the project you are composing. The choice is yours. + +.. note:: + + If you're using manually configured settings, as described in + :ref:`settings-without-django-settings-module`, the ``locale`` directory in + the project directory will not be examined, since Django loses the ability + to work out the location of the project directory. (Django normally uses the + location of the settings file to determine this, and a settings file doesn't + exist if you're manually configuring your settings.) + +All message file repositories are structured the same way. They are: + +* All paths listed in :setting:`LOCALE_PATHS` in your settings file are + searched for ``/LC_MESSAGES/django.(po|mo)`` +* ``$PROJECTPATH/locale//LC_MESSAGES/django.(po|mo)`` -- + deprecated, see above. +* ``$APPPATH/locale//LC_MESSAGES/django.(po|mo)`` +* ``$PYTHONPATH/django/conf/locale//LC_MESSAGES/django.(po|mo)`` + +To create message files, you use the :djadmin:`django-admin.py makemessages ` +tool. You only need to be in the same directory where the ``locale/`` directory +is located. And you use :djadmin:`django-admin.py compilemessages ` +to produce the binary ``.mo`` files that are used by ``gettext``. + +You can also run :djadmin:`django-admin.py compilemessages +--settings=path.to.settings ` to make the compiler process all +the directories in your :setting:`LOCALE_PATHS` setting. + +Finally, you should give some thought to the structure of your translation +files. If your applications need to be delivered to other users and will be used +in other projects, you might want to use app-specific translations. But using +app-specific translations and project-specific translations could produce weird +problems with :djadmin:`makemessages`: it will traverse all directories below +the current path and so might put message IDs into a unified, common message +file for the current project that are already in application message files. + +The easiest way out is to store applications that are not part of the project +(and so carry their own translations) outside the project tree. That way, +:djadmin:`django-admin.py makemessages `, when ran on a project +level will only extract strings that are connected to your explicit project and +not strings that are distributed independently.