Internationalization/Translations - Technical Set-up¶
Translating database content¶
Content in the database is user created content and cannot be translated using the normal gettext interface that Django provides. Instead a package called django-modeltranslation provides for language-specific mirrored fields in the database that allow for content specific translation.
Specifying models and fields for translation¶
Translations are registered much like admin.ModelAdmin classes in a translation.py file in each app root. For each model to translate create a translation class based on the TranslationOptions class, and specify the fields.:
from modeltranslation.translator import translator, TranslationOptions from orb import models class CategoryTranslation(TranslationOptions): fields = ('name',) translator.register(models.Category, CategoryTranslation)
In the above example the CategoryTranslation class specifies only that the name field should be translated, and the Category model is registered with this translation options class.
Realizing new translation fields¶
Field registration is by itself an insufficient step. It is like adding new fields to a model - you still need to create a database migration to realize the field(s). This is straightforward 3-step process.
- Run makemigrations for the app in question
- Apply the migrations with migrate
- Update the translation fields with the update_translation_fields command
The third step is important because of how modeltranslations pulls data out of the database. If you have a name field and then decide to translate it, then presuming an English language site with Spanish and Portuguese available as well, you will have four database fields: name, name_en, name_es, and name_pt.
Dialect or region specific codes will have their own fields if specified, e.g. name_pt_br.
Once active, modeltranslation will look for the name value in name_en! Running update_translation_fields updates those values.
A convenience command has been added to the Makefile:
This will create migrations, apply them, and then update the translation fields.
You must create new migrations any time you register new models/fields and also if you change the project LANGUAGES setting, so that database fields are available for each language.