Add new generic "notes" model

src/backend/InvenTree/InvenTree/models.py

@@ -632,14 +632,14 @@ class InvenTreeParameterMixin(InvenTreePermissionCheckMixin, models.Model):
 
         return params
 
-    def check_parameter_delete(self, parameter):
+    def check_parameter_delete(self, parameter) -> bool:
         """Run a check to determine if the provided parameter can be deleted.
 
         The default implementation always returns True, but this can be overridden in the implementing class.
         """
         return True
 
-    def check_parameter_save(self, parameter):
+    def check_parameter_save(self, parameter) -> bool:
         """Run a check to determine if the provided parameter can be saved.
 
         The default implementation always returns True, but this can be overridden in the implementing class.
@@ -647,6 +647,84 @@ class InvenTreeParameterMixin(InvenTreePermissionCheckMixin, models.Model):
         return True
 
 
+class InvenTreeNoteMixin(InvenTreePermissionCheckMixin):
+    """Provides an abstracted class for managing notes.
+
+    Links the implementing model to the common.models.Note table,
+    and provides multiple accessor / helper methods.
+    """
+
+    class Meta:
+        """Metaclass options for InvenTreeNoteMixin."""
+
+        abstract = True
+
+    # Define a reverse relation to the Note model
+    notes_list = GenericRelation(
+        'common.Note', content_type_field='model_type', object_id_field='model_id'
+    )
+
+    @property
+    def notes(self) -> QuerySet:
+        """Return a queryset containing all notes for this model."""
+        # Check the query cache for pre-fetched parameters
+        if cache := getattr(self, '_prefetched_objects_cache', None):
+            if 'notes_list' in cache:
+                return cache['notes_list']
+
+        return self.notes_list.all()
+
+    def delete(self, *args, **kwargs):
+        """Handle the deletion of a model instance.
+
+        Before deleting the model instance, delete any associated notes.
+        """
+        self.notes_list.all().delete()
+        super().delete(*args, **kwargs)
+
+    @transaction.atomic
+    def copy_notes_from(self, other, **kwargs):
+        """Copy all notes from another model instance.
+
+        Arguments:
+            other: The other model instance to copy notes from
+            **kwargs: Additional keyword arguments to pass to the Note constructor
+        """
+        import common.models
+
+        notes = []
+
+        content_type = ContentType.objects.get_for_model(self.__class__)
+
+        for note in other.notes.all():
+            note.pk = None
+            note.model_id = self.pk
+            note.model_type = content_type
+
+            notes.append(note)
+
+        if len(notes) > 0:
+            common.models.Note.objects.bulk_create(notes, batch_size=250)
+
+    def get_note(self, title: str):
+        """Return a Note instance for the given note title."""
+        return self.notes_list.filter(title=title).first()
+
+    def check_note_delete(self, note) -> bool:
+        """Run a check to determine if the provided note can be deleted.
+
+        The default implementation always returns True, but this can be overridden in the implementing class.
+        """
+        return True
+
+    def check_note_save(self, note) -> bool:
+        """Run a check to determine if the provided note can be saved.
+
+        The default implementation always returns True, but this can be overridden in the implementing class.
+        """
+        return True
+
+
 class InvenTreeAttachmentMixin(InvenTreePermissionCheckMixin):
     """Provides an abstracted class for managing file attachments.
 

src/backend/InvenTree/common/migrations/0042_note.py

@@ -0,0 +1,95 @@
+# Generated by Django 5.2.14 on 2026-05-18 13:55
+
+import InvenTree.models
+import django.db.models.deletion
+from django.conf import settings
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("common", "0041_auto_20251203_1244"),
+        ("contenttypes", "0002_remove_content_type_name"),
+        migrations.swappable_dependency(settings.AUTH_USER_MODEL),
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name="Note",
+            fields=[
+                (
+                    "id",
+                    models.AutoField(
+                        auto_created=True,
+                        primary_key=True,
+                        serialize=False,
+                        verbose_name="ID",
+                    ),
+                ),
+                (
+                    "metadata",
+                    models.JSONField(
+                        blank=True,
+                        help_text="JSON metadata field, for use by external plugins",
+                        null=True,
+                        verbose_name="Plugin Metadata",
+                    ),
+                ),
+                (
+                    "updated",
+                    models.DateTimeField(
+                        blank=True,
+                        default=None,
+                        help_text="Timestamp of last update",
+                        null=True,
+                        verbose_name="Updated",
+                    ),
+                ),
+                ("model_id", models.PositiveIntegerField()),
+                (
+                    "title",
+                    models.CharField(
+                        help_text="Note title", max_length=100, verbose_name="Title"
+                    ),
+                ),
+                (
+                    "description",
+                    models.CharField(
+                        blank=True,
+                        help_text="Optional description field",
+                        max_length=250,
+                        verbose_name="Description",
+                    ),
+                ),
+                (
+                    "model_type",
+                    models.ForeignKey(
+                        on_delete=django.db.models.deletion.CASCADE,
+                        to="contenttypes.contenttype",
+                    ),
+                ),
+                (
+                    "updated_by",
+                    models.ForeignKey(
+                        blank=True,
+                        help_text="User who last updated this object",
+                        null=True,
+                        on_delete=django.db.models.deletion.SET_NULL,
+                        related_name="%(class)s_updated",
+                        to=settings.AUTH_USER_MODEL,
+                        verbose_name="Update By",
+                    ),
+                ),
+            ],
+            options={
+                "verbose_name": "Note",
+                "verbose_name_plural": "Notes",
+            },
+            bases=(
+                InvenTree.models.ContentTypeMixin,
+                InvenTree.models.PluginValidationMixin,
+                models.Model,
+            ),
+        ),
+    ]

src/backend/InvenTree/common/models.py

@@ -2906,6 +2906,88 @@ class Parameter(
         return self.template.description
 
 
+class Note(
+    UpdatedUserMixin, InvenTree.models.MetadataMixin, InvenTree.models.InvenTreeModel
+):
+    """Class which represents a note assigned to a particular model instance.
+
+    Attributes:
+        model_type: The type of model to which this note is linked
+        model_id: The ID of the model to which this note is linked
+        user: The user who created the note
+        title: The title of the note
+        description: A description of the note (optional)
+        content: The content of the note
+        created: Date/time that the note was created
+    """
+
+    class Meta:
+        """Meta options for Note model."""
+
+        verbose_name = _('Note')
+        verbose_name_plural = _('Notes')
+
+    @staticmethod
+    def get_api_url() -> str:
+        """Return the API URL associated with the Parameter model."""
+        return reverse('api-note-list')
+
+    def save(self, *args, **kwargs):
+        """Perform custom save checks before saving a Note instance."""
+        self.check_save()
+        super().save(*args, **kwargs)
+
+    def delete(self):
+        """Perform custom delete checks before deleting a Parameter instance."""
+        self.check_delete()
+        super().delete()
+
+    def clean(self):
+        """Clean / validate the note before saving to the database."""
+        # TODO: Implement this
+
+    def check_save(self):
+        """Check if this note can be saved."""
+        from InvenTree.models import InvenTreeNoteMixin
+
+        try:
+            instance = self.content_object
+        except InvenTree.models.InvenTreeModel.DoesNotExist:
+            return
+
+        if instance and isinstance(instance, InvenTreeNoteMixin):
+            instance.check_note_save(self)
+
+    def check_delete(self):
+        """Check if this note can be deleted."""
+        from InvenTree.models import InvenTreeNoteMixin
+
+        try:
+            instance = self.content_object
+        except InvenTree.models.InvenTreeModel.DoesNotExist:
+            return
+
+        if instance and isinstance(instance, InvenTreeNoteMixin):
+            instance.check_note_delete(self)
+
+    model_type = models.ForeignKey(ContentType, on_delete=models.CASCADE)
+
+    model_id = models.PositiveIntegerField()
+
+    content_object = GenericForeignKey('model_type', 'model_id')
+
+    title = models.CharField(
+        max_length=100, verbose_name=_('Title'), help_text=_('Note title')
+    )
+
+    description = models.CharField(
+        max_length=250,
+        blank=True,
+        verbose_name=_('Description'),
+        help_text=_('Optional description field'),
+    )
+
+
 class BarcodeScanResult(InvenTree.models.InvenTreeModel):
     """Model for storing barcode scans results."""