Getting ready

Let's create a new app called ideas and put it in INSTALLED_APPS in the settings. Create the following Idea model with an IdeaTranslations model for translations inside of that app:

# myproject/apps/idea/models.py
import uuid

from django.db import models
from django.urls import reverse
from django.conf import settings
from django.utils.translation import gettext_lazy as _

from myproject.apps.core.model_fields import TranslatedField
from myproject.apps.core.models import (
    CreationModificationDateBase, UrlBase
)

RATING_CHOICES = (
    (1, "★☆☆☆☆"), 
    (2, "★★☆☆☆"), 
    (3, "★★★☆☆"), 
    (4, "★★★★☆"),
    (5, "★★★★★"),
)


class Idea(CreationModificationDateBase, UrlBase):
    uuid = models.UUIDField(
        primary_key=True, default=uuid.uuid4, editable=False
    )
    author = models.ForeignKey(
        settings.AUTH_USER_MODEL,
        verbose_name=_("Author"),
        on_delete=models.SET_NULL,
        blank=True,
        null=True,
        related_name="authored_ideas",
    )
    title = models.CharField(_("Title"), max_length=200)
    content = models.TextField(_("Content"))

    categories = models.ManyToManyField(
        "categories.Category",
        verbose_name=_("Categories"),
        related_name="category_ideas",
    )
    rating = models.PositiveIntegerField(
        _("Rating"), choices=RATING_CHOICES, blank=True, null=True
    )
    translated_title = TranslatedField("title")
    translated_content = TranslatedField("content")

    class Meta:
        verbose_name = _("Idea")
        verbose_name_plural = _("Ideas")

    def __str__(self):
        return self.title

    def get_url_path(self):
        return reverse("ideas:idea_detail", kwargs={"pk": self.pk})


class IdeaTranslations(models.Model):
    idea = models.ForeignKey(
        Idea,
        verbose_name=_("Idea"),
        on_delete=models.CASCADE,
        related_name="translations",
    )
    language = models.CharField(_("Language"), max_length=7)

    title = models.CharField(_("Title"), max_length=200)
    content = models.TextField(_("Content"))

    class Meta:
        verbose_name = _("Idea Translations")
        verbose_name_plural = _("Idea Translations")
        ordering = ["language"]
        unique_together = [["idea", "language"]]

    def __str__(self):
        return self.title

We are using several concepts here from the previous chapter: we inherit from model mixins and utilize a model translation table. Read more about that in the Using model mixins and the Working with model translation tables recipes. We are going to use the ideas app and these models for all of the recipes in this chapter.

In addition, create an analogous categories app with the Category and CategoryTranslations models:

# myproject/apps/categories/models.py
from django.db import models
from django.utils.translation import gettext_lazy as _

from myproject.apps.core.model_fields import TranslatedField


class Category(models.Model):
    title = models.CharField(_("Title"), max_length=200)

    translated_title = TranslatedField("title")

    class Meta:
        verbose_name = _("Category")
        verbose_name_plural = _("Categories")

    def __str__(self):
        return self.title


class CategoryTranslations(models.Model):
    category = models.ForeignKey(
        Category,
        verbose_name=_("Category"),
        on_delete=models.CASCADE,
        related_name="translations",
    )
    language = models.CharField(_("Language"), max_length=7)

    title = models.CharField(_("Title"), max_length=200)

    class Meta:
        verbose_name = _("Category Translations")
        verbose_name_plural = _("Category Translations")
        ordering = ["language"]
        unique_together = [["category", "language"]]

    def __str__(self):
        return self.title