tornado.locale
— Internationalization support¶
Translation methods for generating localized strings.
To load a locale and generate a translated string:
user_locale = tornado.locale.get("es_LA")
print(user_locale.translate("Sign out"))
tornado.locale.get()
returns the closest matching locale, not necessarily the
specific locale you requested. You can support pluralization with
additional arguments to translate()
, e.g.:
people = [...]
message = user_locale.translate(
"%(list)s is online", "%(list)s are online", len(people))
print(message % {"list": user_locale.list(people)})
The first string is chosen if len(people) == 1
, otherwise the second
string is chosen.
Applications should call one of load_translations
(which uses a simple
CSV format) or load_gettext_translations
(which uses the .mo
format
supported by gettext
and related tools). If neither method is called,
the Locale.translate
method will simply return the original string.
-
tornado.locale.
get
(*locale_codes) → tornado.locale.Locale[source]¶ Returns the closest match for the given locale codes.
We iterate over all given locale codes in order. If we have a tight or a loose match for the code (e.g., “en” for “en_US”), we return the locale. Otherwise we move to the next code in the list.
By default we return
en_US
if no translations are found for any of the specified locales. You can change the default locale withset_default_locale()
.
-
tornado.locale.
set_default_locale
(code: str) → None[source]¶ Sets the default locale.
The default locale is assumed to be the language used for all strings in the system. The translations loaded from disk are mappings from the default locale to the destination locale. Consequently, you don’t need to create a translation file for the default locale.
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tornado.locale.
load_translations
(directory: str, encoding: Optional[str] = None) → None[source]¶ Loads translations from CSV files in a directory.
Translations are strings with optional Python-style named placeholders (e.g.,
My name is %(name)s
) and their associated translations.The directory should have translation files of the form
LOCALE.csv
, e.g.es_GT.csv
. The CSV files should have two or three columns: string, translation, and an optional plural indicator. Plural indicators should be one of “plural” or “singular”. A given string can have both singular and plural forms. For example%(name)s liked this
may have a different verb conjugation depending on whether %(name)s is one name or a list of names. There should be two rows in the CSV file for that string, one with plural indicator “singular”, and one “plural”. For strings with no verbs that would change on translation, simply use “unknown” or the empty string (or don’t include the column at all).The file is read using the
csv
module in the default “excel” dialect. In this format there should not be spaces after the commas.If no
encoding
parameter is given, the encoding will be detected automatically (among UTF-8 and UTF-16) if the file contains a byte-order marker (BOM), defaulting to UTF-8 if no BOM is present.Example translation
es_LA.csv
:"I love you","Te amo" "%(name)s liked this","A %(name)s les gustó esto","plural" "%(name)s liked this","A %(name)s le gustó esto","singular"
Changed in version 4.3: Added
encoding
parameter. Added support for BOM-based encoding detection, UTF-16, and UTF-8-with-BOM.
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tornado.locale.
load_gettext_translations
(directory: str, domain: str) → None[source]¶ Loads translations from
gettext
’s locale treeLocale tree is similar to system’s
/usr/share/locale
, like:{directory}/{lang}/LC_MESSAGES/{domain}.mo
Three steps are required to have your app translated:
Generate POT translation file:
xgettext --language=Python --keyword=_:1,2 -d mydomain file1.py file2.html etc
Merge against existing POT file:
msgmerge old.po mydomain.po > new.po
Compile:
msgfmt mydomain.po -o {directory}/pt_BR/LC_MESSAGES/mydomain.mo
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tornado.locale.
get_supported_locales
() → Iterable[str][source]¶ Returns a list of all the supported locale codes.
-
class
tornado.locale.
Locale
(code: str)[source]¶ Object representing a locale.
After calling one of
load_translations
orload_gettext_translations
, callget
orget_closest
to get a Locale object.-
classmethod
get_closest
(*locale_codes) → tornado.locale.Locale[source]¶ Returns the closest match for the given locale code.
-
classmethod
get
(code: str) → tornado.locale.Locale[source]¶ Returns the Locale for the given locale code.
If it is not supported, we raise an exception.
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translate
(message: str, plural_message: Optional[str] = None, count: Optional[int] = None) → str[source]¶ Returns the translation for the given message for this locale.
If
plural_message
is given, you must also providecount
. We returnplural_message
whencount != 1
, and we return the singular form for the given message whencount == 1
.
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format_date
(date: Union[int, float, datetime.datetime], gmt_offset: int = 0, relative: bool = True, shorter: bool = False, full_format: bool = False) → str[source]¶ Formats the given date (which should be GMT).
By default, we return a relative time (e.g., “2 minutes ago”). You can return an absolute date string with
relative=False
.You can force a full format date (“July 10, 1980”) with
full_format=True
.This method is primarily intended for dates in the past. For dates in the future, we fall back to full format.
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format_day
(date: datetime.datetime, gmt_offset: int = 0, dow: bool = True) → bool[source]¶ Formats the given date as a day of week.
Example: “Monday, January 22”. You can remove the day of week with
dow=False
.
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classmethod
-
class
tornado.locale.
CSVLocale
(code: str, translations: Dict[str, Dict[str, str]])[source]¶ Locale implementation using tornado’s CSV translation format.
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class
tornado.locale.
GettextLocale
(code: str, translations: gettext.NullTranslations)[source]¶ Locale implementation using the
gettext
module.-
pgettext
(context: str, message: str, plural_message: Optional[str] = None, count: Optional[int] = None) → str[source]¶ Allows to set context for translation, accepts plural forms.
Usage example:
pgettext("law", "right") pgettext("good", "right")
Plural message example:
pgettext("organization", "club", "clubs", len(clubs)) pgettext("stick", "club", "clubs", len(clubs))
To generate POT file with context, add following options to step 1 of
load_gettext_translations
sequence:xgettext [basic options] --keyword=pgettext:1c,2 --keyword=pgettext:1c,2,3
New in version 4.2.
-