Query by active lang

[brahica]

Hi,

Just asking, there is a ways filtring by active lang like :

from django.db import models
from localized_fields.fields import LocalizedCharField
from localized_fields.models import LocalizedModel
from django.utils.translation import activate

class MyModel(LocalizedModel, models.Model):
    name = LocalizedCharField(required=True)

"""
If MyModel instance are:
{
'name': {
        'en': foo,
        'es': bar
    }
}
"""

activate('en')    # Active lang 'en'
MyModel.objects.filter(name='foo')    # Find all instance that have name['en'] = 'foo'
MyModel.objects.filter(name__contains='foo')    # Find all instance that have name['en'] = '%foo%'

Thx ;)

[seroy]

LocalizedField is HStoreField with language codes as keys:

MyModel.objects.filter(name__en='foo') # Find all instance that have name['en'] = 'foo'
MyModel.objects.filter(name__en__contains='foo')    # Find all instance that have name['en'] = '%foo%'

See HStoreField Key lookups on Django Docs

[seroy]

Oops, am re-read the question. Seems currently is no way to do this.

[si14]

Hey @brahica, I would argue that's a bad design. "Active language" is an implicit thread-local state which is most often set during the request handling, so it's best to keep it contained in your views and templates. Lookup like that will break in unexpected ways if you use it in Celery or management tasks.

[sliverc]

@si14 I guess the problem you mention we already have as localized fields depend on thread local state e.g. when calling my_model.name = 'Test' will set Test in current language.

This said I would love to see such a feature as well.

[sliverc]

As I needed this I have created following search lookup snippet for localized fields in my projects. Potentially can be used as an example to implement other lookups as well.

from django.contrib.postgres.fields.hstore import KeyTransform
from django.contrib.postgres.search import (SearchVector, SearchVectorExact,
                                            SearchVectorField)
from django.utils import translation
from localized_fields.fields import LocalizedField


class LocalizedSearchLookup(SearchVectorExact):
    lookup_name = 'search'

    def process_lhs(self, qn, connection):
        if not isinstance(self.lhs.output_field, SearchVectorField):
            self.lhs = SearchVector(
                KeyTransform(translation.get_language(), self.lhs)
            )
        return super().process_lhs(qn, connection)

    def get_prep_lookup(self):
        return str(self.rhs)


LocalizedField.register_lookup(LocalizedSearchLookup)