16 april 2026 · 1 min leestijd

Snippets Wagtail and Wagtail localize, a gotcha

A tip when working with Wagtail-localize and using snippets to set filters.

Onno Timmerman

Oprichter & lead engineer

Suppose you have a page with related tags added via snippets, and you want to query all pages with a specific tag.

When synchronization translation is enabled, the tag refers to the default language. But if the user disables synchronization translation, the tag refers to the language of the page. This may mean that the user is referencing a translated tag within the translated page, causing the query to miss some pages with the original tag.

To solve this, you can retrieve both the default language and the current language and then filter based on the active language.

python

from django.db import models
from django.db.models import Q
from django.utils.translation import gettext_lazy as _ 
from wagtail.snippets.models import register_snippet
from wagtail.models import TranslatableMixin, Page
 
 
@register_snippet
class Tag(TranslatableMixin, models.Model):
    tag = models.CharField(_("Tag"), max_length=255)
 
    def __str__(self):
        return self.tag
 
class BlogPage(Page):
    my_tag = models.ForeignKey(
        "snippets.Tag",
        null=True,
        blank=True,
        on_delete=models.SET_NULL,
        related_name="+",
    )
 
    def get_context(self, request, *args, **kwargs):
        context = super().get_context(request, *args, **kwargs)
        if self.my_tag:
            default_tag = self.my_tag.get_translation(self.my_tag.get_default_locale())
            context['pages'] = BlogPage.objects.live().filter(Q(locale=self.locale), Q(my_tag=default_tag) | Q(my_tag=self.my_tag)).distinct()
            return context