update

apps/core/models.py

@@ -0,0 +1,119 @@
+from django.db import models
+from django.contrib.contenttypes.fields import GenericForeignKey
+from django.contrib.contenttypes.models import ContentType
+from django.utils.text import slugify
+from apps.core.history import TrackedModel
+import pghistory
+
+
+@pghistory.track()
+class SlugHistory(models.Model):
+    """
+    Model for tracking slug changes across all models that use slugs.
+    Uses generic relations to work with any model.
+    """
+
+    content_type = models.ForeignKey(ContentType, on_delete=models.CASCADE)
+    object_id = models.CharField(
+        max_length=50
+    )  # Using CharField to work with our custom IDs
+    content_object = GenericForeignKey("content_type", "object_id")
+
+    old_slug = models.SlugField(max_length=200)
+    created_at = models.DateTimeField(auto_now_add=True)
+
+    class Meta:
+        indexes = [
+            models.Index(fields=["content_type", "object_id"]),
+            models.Index(fields=["old_slug"]),
+        ]
+        verbose_name_plural = "Slug histories"
+        ordering = ["-created_at"]
+
+    def __str__(self):
+        return f"Old slug '{self.old_slug}' for {self.content_object}"
+
+
+class SluggedModel(TrackedModel):
+    """
+    Abstract base model that provides slug functionality with history tracking.
+    """
+
+    name = models.CharField(max_length=200)
+    slug = models.SlugField(max_length=200, unique=True)
+
+    class Meta(TrackedModel.Meta):
+        abstract = True
+
+    def save(self, *args, **kwargs):
+        # Get the current instance from DB if it exists
+        if self.pk:
+            try:
+                old_instance = self.__class__.objects.get(pk=self.pk)
+                # If slug has changed, save the old one to history
+                if old_instance.slug != self.slug:
+                    SlugHistory.objects.create(
+                        content_type=ContentType.objects.get_for_model(self),
+                        object_id=getattr(self, self.get_id_field_name()),
+                        old_slug=old_instance.slug,
+                    )
+            except self.__class__.DoesNotExist:
+                pass
+
+        # Generate slug if not set
+        if not self.slug:
+            self.slug = slugify(self.name)
+
+        super().save(*args, **kwargs)
+
+    def get_id_field_name(self):
+        """
+        Returns the name of the read-only ID field for this model.
+        Should be overridden by subclasses.
+        """
+        raise NotImplementedError(
+            "Subclasses of SluggedModel must implement get_id_field_name()"
+        )
+
+    @classmethod
+    def get_by_slug(cls, slug):
+        """
+        Get an object by its current or historical slug.
+        Returns (object, is_old_slug) tuple.
+        """
+        try:
+            # Try to get by current slug first
+            return cls.objects.get(slug=slug), False
+        except cls.DoesNotExist:
+            # Check pghistory first if available
+            try:
+                import pghistory.models
+
+                history_entries = pghistory.models.Events.objects.filter(
+                    pgh_model=f"{cls._meta.app_label}.{cls._meta.model_name}", slug=slug
+                ).order_by("-pgh_created_at")
+
+                if history_entries:
+                    history_entry = history_entries.first()
+                    if history_entry:
+                        return cls.objects.get(id=history_entry.pgh_obj_id), True
+            except (ImportError, AttributeError):
+                pass
+
+            # Try to find in manual slug history as fallback
+            history = (
+                SlugHistory.objects.filter(
+                    content_type=ContentType.objects.get_for_model(cls),
+                    old_slug=slug,
+                )
+                .order_by("-created_at")
+                .first()
+            )
+
+            if history:
+                return (
+                    cls.objects.get(**{cls().get_id_field_name(): history.object_id}),
+                    True,
+                )
+
+            raise cls.DoesNotExist(f"{cls.__name__} with slug '{slug}' does not exist")