seroy / django-localized-fields

Implementation of localized model fields using PostgreSQL HStore fields.

django-localized-fields

django-localized-fields is an implementation of a field class for Django models that allows the field's value to be set in multiple languages. It does this by utilizing the hstore type (PostgreSQL specific), which is available as models.HStoreField in Django 1.10.

This package requires Python 3.5 or newer and Django 1.10 or newer.

In the pipeline

We're working on making this easier to setup and use. Any feedback is apreciated. Here's a short list of things we're working to improve:

• Make it unnecesarry to add anything to your INSTALLED_APPS.
• Make it unnecesarry to modify your migrations manually to enable the PostgreSQL HStore extension.

Installation

1. Install the package from PyPi:

   $ pip install django-localized-fields

2. Add localized_fields and django.contrib.postgres to your INSTALLED_APPS:

   INSTALLED_APPS = [
       ....
   
       'django.contrib.postgres',
       'localized_fields'
   ]

3. Set LANGUAGES` and `LANGUAGE_CODE in your settings:

   LANGUAGE_CODE = 'en' # default language
   LANGUAGES = (
       ('en', 'English'),
       ('nl', 'Dutch'),
       ('ro', 'Romanian')
   )

Usage

Preparation

Declare fields on your model as LocalizedField:

from localized_fields.fields import LocalizedField


class MyModel(models.Model):
    title = LocalizedField()

Create your migrations using python manage.py makemigrations. Open the generated migration in your favorite editor and setup the HStore extension before the first CreateModel or AddField operation by adding a migration with the HStoreExtension operation. For example:

from django.contrib.postgres.operations import HStoreExtension

class Migration(migrations.Migration):
    ...

    operations = [
        HStoreExtension(),
        ...
    ]

Then apply the migration using python manage.py migrate.

django-localized-fields integrates with Django's i18n system, in order for certain languages to be available you have to correctly configure the LANGUAGES and LANGUAGE_CODE settings:

LANGUAGE_CODE = 'en' # default language
LANGUAGES = (
     ('en', 'English'),
     ('nl', 'Dutch'),
     ('ro', 'Romanian')
)

Basic usage

new = MyModel()
new.title.en = 'english title'
new.title.nl = 'dutch title'
new.title.ro = 'romanian title'
new.save()

By changing the active language you can control which language is presented:

from django.utils import translation

translation.activate('nl')
print(new.title) # prints 'dutch title'

translation.activate('en')
print(new.title) # prints 'english title'

Or get it in a specific language:

print(new.title.get('en')) # prints 'english title'
print(new.title.get('ro')) # prints 'romanian title'
print(new.title.get()) # whatever language is the primary one

You can also explicitly set a value in a certain language:

new.title.set('en', 'other english title')
new.title.set('nl', 'other dutch title')

new.title.ro = 'other romanian title'

Or set a value for current active language:

translation.activate('nl')
new.title = 'other dutch title'

translation.activate('en')
new.title = 'other english title'

new.save()

Constraints

By default, the following constraints apply to a LocalizedField:

• Only the default language is required. The other languages are optional and can be NULL.
• If null=True is specified on the LocalizedField, then none of the languages are required.

At the moment it is not possible to specifically instruct LocalizedField to mark certain languages as required or optional.

Other fields

Besides LocalizedField, there's also:

• LocalizedAutoSlugField

  Automatically creates a slug for every language from the specified field. Depends upon:

  • django-autoslug

  Currently only supports populate_from. Example usage:

  from localized_fields.fields import (LocalizedField,
                                       LocalizedAutoSlugField)
  
  class MyModel(models.Model):
       title = LocalizedField()
       slug = LocalizedAutoSlugField(populate_from='title')

• LocalizedBleachField

  Automatically bleaches the content of the field.

  • django-bleach

  Example usage:

  from localized_fields.fields import (LocalizedField,
                                       LocalizedBleachField)
  
  class MyModel(models.Model):
       title = LocalizedField()
       description = LocalizedBleachField()

• LocalizedCharField and LocalizedTextField

  Instead of LocalizedField save empty strings as '', this is a Django convention.

  LocalizedCharField uses form.TextInput widget.

  Example usage:

  from localized_fields.fields import (LocalizedCharField,
                                       LocalizedTextField)
  
  
  class MyModel(models.Model):
       title = LocalizedCharField()
       content = LocalizedTextField()

Django Admin Integration

To enable widgets in the admin, you need to inherit from LocalizedFieldsAdminMixin:

from django.contrib import admin
from myapp.models import MyLocalizedModel

from localized_fields.admin import LocalizedFieldsAdminMixin


class MyLocalizedModelAdmin(LocalizedFieldsAdminMixin, admin.ModelAdmin):
    """Any admin options you need go here"""

admin.site.register(MyLocalizedModel, MyLocalizedModelAdmin)