Refactoring: improving backend

2025-06-25 20:40:36 +03:00 · 2024-07-22 21:20:51 +03:00 · 2024-07-22 21:20:51 +03:00 · 8697ee6175
commit 8697ee6175
parent cdb2f6cb79
41 changed files with 530 additions and 257 deletions
--- a/.dockerignore
+++ b/.dockerignore
@ -47,6 +47,7 @@ cover/
 # Django
 rsconcept/frontend/static
 rsconcept/frontend/media
+visualizeDB.dot
 *.log
 db.sqlite3
 db.sqlite3-journal
--- a/.gitignore
+++ b/.gitignore
@ -42,6 +42,7 @@ cover/
 *.log
 db.sqlite3
 db.sqlite3-journal
+visualizeDB.dot


 # React
--- a/.vscode/launch.json
+++ b/.vscode/launch.json
@ -5,6 +5,7 @@
  "version": "0.2.0",
  "configurations": [
    {
+      // Run Frontend + Backend with current Database
      "name": "Run",
      "type": "PowerShell",
      "request": "launch",
@ -12,6 +13,7 @@
      "args": []
    },
    {
+      // Run Linters
      "name": "Lint",
      "type": "PowerShell",
      "request": "launch",
@ -19,6 +21,7 @@
      "args": []
    },
    {
+      // Run Tests
      "name": "Test",
      "type": "PowerShell",
      "request": "launch",
@ -26,6 +29,7 @@
      "args": []
    },
    {
+      // Run Tests for backend for current file in Debug mode
      "name": "BE-DebugTestFile",
      "type": "debugpy",
      "request": "launch",
@ -35,6 +39,7 @@
      "django": true
    },
    {
+      // Run Tests for frontned in Debug mode
      "name": "FE-DebugTestAll",
      "type": "node",
      "request": "launch",
@ -55,6 +60,7 @@
      }
    },
    {
+      // Run Browser in Debug mode (Backend should be running)
      "name": "FE-Debug",
      "type": "chrome",
      "request": "launch",
@ -62,6 +68,7 @@
      "webRoot": "${workspaceFolder}/rsconcept/frontend"
    },
    {
+      // Run Backend in Debug mode
      "name": "BE-Debug",
      "type": "debugpy",
      "request": "launch",
@ -70,6 +77,7 @@
      "django": true
    },
    {
+      // Run Backend test coverage
      "name": "BE-Coverage",
      "type": "PowerShell",
      "request": "launch",
@ -77,11 +85,20 @@
      "args": []
    },
    {
+      // Recreate database, fill with initial data and Run Backend + Frontend
      "name": "Restart",
      "type": "PowerShell",
      "request": "launch",
      "script": "${workspaceFolder}/scripts/dev/RunServer.ps1",
      "args": ["-freshStart"]
+    },
+    {
+      // Create DOT file for visualizing database
+      "name": "BE-GraphDB",
+      "type": "PowerShell",
+      "request": "launch",
+      "script": "${workspaceFolder}/scripts/dev/GraphDB.ps1",
+      "args": []
    }
  ]
 }
--- a/rsconcept/backend/apps/oss/admin.py
+++ b/rsconcept/backend/apps/oss/admin.py
@ -7,8 +7,24 @@ from . import models
 class OperationAdmin(admin.ModelAdmin):
    ''' Admin model: Operation. '''
    ordering = ['oss']
-    list_display = ['oss', 'operation_type', 'result', 'alias', 'title', 'comment', 'position_x', 'position_y']
-    search_fields = ['operation_type', 'title', 'alias']
+    list_display = ['id', 'oss', 'operation_type', 'result', 'alias', 'title', 'comment', 'position_x', 'position_y']
+    search_fields = ['id', 'operation_type', 'title', 'alias']
+
+
+class ArgumentAdmin(admin.ModelAdmin):
+    ''' Admin model: Operation arguments. '''
+    ordering = ['operation']
+    list_display = ['id', 'operation', 'argument']
+    search_fields = ['id', 'operation', 'argument']
+
+
+class SynthesisSubstitutionAdmin(admin.ModelAdmin):
+    ''' Admin model:  Substitutions as part of Synthesis operation. '''
+    ordering = ['operation']
+    list_display = ['id', 'operation', 'original', 'substitution', 'transfer_term']
+    search_fields = ['id', 'operation', 'original', 'substitution']


 admin.site.register(models.Operation, OperationAdmin)
+admin.site.register(models.Argument, ArgumentAdmin)
+admin.site.register(models.SynthesisSubstitution, SynthesisSubstitutionAdmin)
--- a/rsconcept/backend/apps/oss/migrations/0002_operationschema_alter_operation_oss.py
+++ b/rsconcept/backend/apps/oss/migrations/0002_operationschema_alter_operation_oss.py
@ -0,0 +1,31 @@
+# Generated by Django 5.0.7 on 2024-07-22 13:23
+
+import django.db.models.deletion
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('oss', '0001_initial'),
+        ('rsform', '0008_alter_libraryitem_item_type'),
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name='OperationSchema',
+            fields=[
+            ],
+            options={
+                'proxy': True,
+                'indexes': [],
+                'constraints': [],
+            },
+            bases=('rsform.libraryitem',),
+        ),
+        migrations.AlterField(
+            model_name='operation',
+            name='oss',
+            field=models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='items', to='oss.operationschema', verbose_name='Схема синтеза'),
+        ),
+    ]
--- a/rsconcept/backend/apps/oss/models/Argument.py
+++ b/rsconcept/backend/apps/oss/models/Argument.py
@ -24,4 +24,4 @@ class Argument(Model):
        unique_together = [['operation', 'argument']]

    def __str__(self) -> str:
-        return f'{self.argument.pk} -> {self.operation.pk}'
+        return f'{self.argument} -> {self.operation}'
--- a/rsconcept/backend/apps/oss/models/Operation.py
+++ b/rsconcept/backend/apps/oss/models/Operation.py
@ -21,7 +21,7 @@ class Operation(Model):
    ''' Operational schema Unit.'''
    oss: ForeignKey = ForeignKey(
        verbose_name='Схема синтеза',
-        to='rsform.LibraryItem',
+        to='oss.OperationSchema',
        on_delete=CASCADE,
        related_name='items'
    )
--- a/rsconcept/backend/apps/oss/models/OperationSchema.py
+++ b/rsconcept/backend/apps/oss/models/OperationSchema.py
@ -3,7 +3,7 @@ from typing import Optional

 from django.core.exceptions import ValidationError
 from django.db import transaction
-from django.db.models import QuerySet
+from django.db.models import Manager, QuerySet

 from apps.rsform.models import LibraryItem, LibraryItemType
 from shared import messages as msg
@ -13,30 +13,37 @@ from .Operation import Operation
 from .SynthesisSubstitution import SynthesisSubstitution


-class OperationSchema:
+class OperationSchema(LibraryItem):
    ''' Operations schema API. '''

-    def __init__(self, item: LibraryItem):
-        if item.item_type != LibraryItemType.OPERATION_SCHEMA:
-            raise ValueError(msg.libraryTypeUnexpected())
-        self.item = item
+    class Meta:
+        ''' Model metadata. '''
+        proxy = True

-    @staticmethod
-    def create(**kwargs) -> 'OperationSchema':
-        item = LibraryItem.objects.create(item_type=LibraryItemType.OPERATION_SCHEMA, **kwargs)
-        return OperationSchema(item=item)
+    class InternalManager(Manager):
+        ''' Object manager. '''
+
+        def get_queryset(self) -> QuerySet:
+            return super().get_queryset().filter(item_type=LibraryItemType.OPERATION_SCHEMA)
+
+        def create(self, **kwargs):
+            kwargs.update({'item_type': LibraryItemType.OPERATION_SCHEMA})
+            return super().create(**kwargs)
+
+    # Legit overriding object manager
+    objects = InternalManager()  # type: ignore[misc]

    def operations(self) -> QuerySet[Operation]:
        ''' Get QuerySet containing all operations of current OSS. '''
-        return Operation.objects.filter(oss=self.item)
+        return Operation.objects.filter(oss=self)

    def arguments(self) -> QuerySet[Argument]:
        ''' Operation arguments. '''
-        return Argument.objects.filter(operation__oss=self.item)
+        return Argument.objects.filter(operation__oss=self)

    def substitutions(self) -> QuerySet[SynthesisSubstitution]:
        ''' Operation substitutions. '''
-        return SynthesisSubstitution.objects.filter(operation__oss=self.item)
+        return SynthesisSubstitution.objects.filter(operation__oss=self)

    def update_positions(self, data: list[dict]):
        ''' Update positions. '''
@ -53,11 +60,8 @@ class OperationSchema:
        ''' Insert new operation. '''
        if kwargs['alias'] != '' and self.operations().filter(alias=kwargs['alias']).exists():
            raise ValidationError(msg.aliasTaken(kwargs['alias']))
-        result = Operation.objects.create(
-            oss=self.item,
-            **kwargs
-        )
-        self.item.save()
+        result = Operation.objects.create(oss=self, **kwargs)
+        self.save()
        result.refresh_from_db()
        return result

@ -69,7 +73,7 @@ class OperationSchema:
        # deal with attached schema
        # trigger on_change effects

-        self.item.save()
+        self.save()

    @transaction.atomic
    def set_input(self, target: Operation, schema: Optional[LibraryItem]):
@ -87,7 +91,7 @@ class OperationSchema:

        # trigger on_change effects

-        self.item.save()
+        self.save()

    @transaction.atomic
    def add_argument(self, operation: Operation, argument: Operation) -> Optional[Argument]:
@ -95,7 +99,7 @@ class OperationSchema:
        if Argument.objects.filter(operation=operation, argument=argument).exists():
            return None
        result = Argument.objects.create(operation=operation, argument=argument)
-        self.item.save()
+        self.save()
        return result

    @transaction.atomic
@ -109,7 +113,7 @@ class OperationSchema:

        # trigger on_change effects

-        self.item.save()
+        self.save()

    @transaction.atomic
    def set_substitutions(self, target: Operation, substitutes: list[dict]):
@ -125,4 +129,4 @@ class OperationSchema:

        # trigger on_change effects

-        self.item.save()
+        self.save()
--- a/rsconcept/backend/apps/oss/models/SynthesisSubstitution.py
+++ b/rsconcept/backend/apps/oss/models/SynthesisSubstitution.py
@ -33,4 +33,4 @@ class SynthesisSubstitution(Model):
        verbose_name_plural = 'Таблицы отождествлений'

    def __str__(self) -> str:
-        return f'{self.original.pk} -> {self.substitution.pk}'
+        return f'{self.original} -> {self.substitution}'
--- a/rsconcept/backend/apps/oss/models/init.py
+++ b/rsconcept/backend/apps/oss/models/init.py
@ -2,7 +2,7 @@

 from apps.rsform.models import LibraryItem, LibraryItemType

-from .api_OSS import OperationSchema
 from .Argument import Argument
 from .Operation import Operation, OperationType
+from .OperationSchema import OperationSchema
 from .SynthesisSubstitution import SynthesisSubstitution
--- a/rsconcept/backend/apps/oss/serializers/data_access.py
+++ b/rsconcept/backend/apps/oss/serializers/data_access.py
@ -85,20 +85,19 @@ class OperationSchemaSerializer(serializers.ModelSerializer):

    class Meta:
        ''' serializer metadata. '''
-        model = LibraryItem
+        model = OperationSchema
        fields = '__all__'

-    def to_representation(self, instance: LibraryItem):
+    def to_representation(self, instance: OperationSchema):
        result = LibraryItemDetailsSerializer(instance).data
-        oss = OperationSchema(instance)
        result['items'] = []
-        for operation in oss.operations():
+        for operation in instance.operations():
            result['items'].append(OperationSerializer(operation).data)
        result['arguments'] = []
-        for argument in oss.arguments():
+        for argument in instance.arguments():
            result['arguments'].append(ArgumentSerializer(argument).data)
        result['substitutions'] = []
-        for substitution in oss.substitutions().values(
+        for substitution in instance.substitutions().values(
            'operation',
            'original',
            'substitution',
--- a/rsconcept/backend/apps/oss/tests/s_models/init.py
+++ b/rsconcept/backend/apps/oss/tests/s_models/init.py
@ -1 +1,4 @@
 ''' Tests for Django Models. '''
+from .t_Argument import *
+from .t_Operation import *
+from .t_SynthesisSubstitution import *
--- a/rsconcept/backend/apps/oss/tests/s_models/t_Argument.py
+++ b/rsconcept/backend/apps/oss/tests/s_models/t_Argument.py
@ -0,0 +1,36 @@
+''' Testing models: Argument. '''
+from django.test import TestCase
+
+from apps.oss.models import Argument, Operation, OperationSchema, OperationType
+
+
+class TestArgument(TestCase):
+    ''' Testing Argument model. '''
+
+    def setUp(self):
+        self.oss = OperationSchema.objects.create(alias='T1')
+
+        self.operation1 = Operation.objects.create(oss=self.oss, alias='KS1', operation_type=OperationType.INPUT)
+        self.operation2 = Operation.objects.create(oss=self.oss, alias='KS2', operation_type=OperationType.SYNTHESIS)
+        self.operation3 = Operation.objects.create(oss=self.oss, alias='KS3', operation_type=OperationType.INPUT)
+        self.argument = Argument.objects.create(
+            operation=self.operation2,
+            argument=self.operation1
+        )
+
+
+    def test_str(self):
+        testStr = f'{self.operation1} -> {self.operation2}'
+        self.assertEqual(str(self.argument), testStr)
+
+
+    def test_cascade_delete_operation(self):
+        self.assertEqual(Argument.objects.count(), 1)
+        self.operation2.delete()
+        self.assertEqual(Argument.objects.count(), 0)
+
+
+    def test_cascade_delete_argument(self):
+        self.assertEqual(Argument.objects.count(), 1)
+        self.operation1.delete()
+        self.assertEqual(Argument.objects.count(), 0)
--- a/rsconcept/backend/apps/oss/tests/s_models/t_Operation.py
+++ b/rsconcept/backend/apps/oss/tests/s_models/t_Operation.py
@ -0,0 +1,31 @@
+''' Testing models: Operation. '''
+from django.test import TestCase
+
+from apps.oss.models import Operation, OperationSchema, OperationType
+
+
+class TestOperation(TestCase):
+    ''' Testing Operation model. '''
+
+    def setUp(self):
+        self.oss = OperationSchema.objects.create(alias='T1')
+        self.operation = Operation.objects.create(
+            oss=self.oss,
+            alias='KS1'
+        )
+
+
+    def test_str(self):
+        testStr = 'Операция KS1'
+        self.assertEqual(str(self.operation), testStr)
+
+
+    def test_create_default(self):
+        self.assertEqual(self.operation.oss, self.oss)
+        self.assertEqual(self.operation.operation_type, OperationType.INPUT)
+        self.assertEqual(self.operation.result, None)
+        self.assertEqual(self.operation.alias, 'KS1')
+        self.assertEqual(self.operation.title, '')
+        self.assertEqual(self.operation.comment, '')
+        self.assertEqual(self.operation.position_x, 0)
+        self.assertEqual(self.operation.position_y, 0)
--- a/rsconcept/backend/apps/oss/tests/s_models/t_SynthesisSubstitution.py
+++ b/rsconcept/backend/apps/oss/tests/s_models/t_SynthesisSubstitution.py
@ -0,0 +1,75 @@
+''' Testing models: SynthesisSubstitution. '''
+from unittest import result
+
+from django.test import TestCase
+
+from apps.oss.models import (
+    Argument,
+    Operation,
+    OperationSchema,
+    OperationType,
+    SynthesisSubstitution
+)
+from apps.rsform.models import RSForm
+
+
+class TestSynthesisSubstitution(TestCase):
+    ''' Testing SynthesisSubstitution model. '''
+
+    def setUp(self):
+        self.oss = OperationSchema.objects.create(alias='T1')
+
+        self.ks1 = RSForm.objects.create(alias='KS1', title='Test1')
+        self.ks1x1 = self.ks1.insert_new('X1', term_resolved='X1_1')
+        self.ks2 = RSForm.objects.create(alias='KS2', title='Test2')
+        self.ks2x1 = self.ks2.insert_new('X2', term_resolved='X1_2')
+
+        self.operation1 = Operation.objects.create(
+            oss=self.oss,
+            alias='KS1',
+            operation_type=OperationType.INPUT,
+            result=self.ks1)
+        self.operation2 = Operation.objects.create(
+            oss=self.oss,
+            alias='KS2',
+            operation_type=OperationType.INPUT,
+            result=self.ks1)
+        self.operation3 = Operation.objects.create(oss=self.oss, alias='KS3', operation_type=OperationType.SYNTHESIS)
+        Argument.objects.create(
+            operation=self.operation3,
+            argument=self.operation1
+        )
+        Argument.objects.create(
+            operation=self.operation3,
+            argument=self.operation2
+        )
+
+        self.substitution = SynthesisSubstitution.objects.create(
+            operation=self.operation3,
+            original=self.ks1x1,
+            substitution=self.ks2x1,
+            transfer_term=False
+        )
+
+
+    def test_str(self):
+        testStr = f'{self.ks1x1} -> {self.ks2x1}'
+        self.assertEqual(str(self.substitution), testStr)
+
+
+    def test_cascade_delete_operation(self):
+        self.assertEqual(SynthesisSubstitution.objects.count(), 1)
+        self.operation3.delete()
+        self.assertEqual(SynthesisSubstitution.objects.count(), 0)
+
+
+    def test_cascade_delete_original(self):
+        self.assertEqual(SynthesisSubstitution.objects.count(), 1)
+        self.ks1x1.delete()
+        self.assertEqual(SynthesisSubstitution.objects.count(), 0)
+
+
+    def test_cascade_delete_substitution(self):
+        self.assertEqual(SynthesisSubstitution.objects.count(), 1)
+        self.ks2x1.delete()
+        self.assertEqual(SynthesisSubstitution.objects.count(), 0)
--- a/rsconcept/backend/apps/oss/tests/s_views/t_oss.py
+++ b/rsconcept/backend/apps/oss/tests/s_views/t_oss.py
@ -12,29 +12,29 @@ class TestOssViewset(EndpointTester):

    def setUp(self):
        super().setUp()
-        self.owned = OperationSchema.create(title='Test', alias='T1', owner=self.user)
-        self.owned_id = self.owned.item.pk
-        self.unowned = OperationSchema.create(title='Test2', alias='T2')
-        self.unowned_id = self.unowned.item.pk
-        self.private = OperationSchema.create(title='Test2', alias='T2', access_policy=AccessPolicy.PRIVATE)
-        self.private_id = self.private.item.pk
-        self.invalid_id = self.private.item.pk + 1337
+        self.owned = OperationSchema.objects.create(title='Test', alias='T1', owner=self.user)
+        self.owned_id = self.owned.pk
+        self.unowned = OperationSchema.objects.create(title='Test2', alias='T2')
+        self.unowned_id = self.unowned.pk
+        self.private = OperationSchema.objects.create(title='Test2', alias='T2', access_policy=AccessPolicy.PRIVATE)
+        self.private_id = self.private.pk
+        self.invalid_id = self.private.pk + 1337


    def populateData(self):
-        self.ks1 = RSForm.create(alias='KS1', title='Test1')
+        self.ks1 = RSForm.objects.create(alias='KS1', title='Test1')
        self.ks1x1 = self.ks1.insert_new('X1', term_resolved='X1_1')
-        self.ks2 = RSForm.create(alias='KS2', title='Test2')
+        self.ks2 = RSForm.objects.create(alias='KS2', title='Test2')
        self.ks2x1 = self.ks2.insert_new('X2', term_resolved='X1_2')
        self.operation1 = self.owned.create_operation(
            alias='1',
            operation_type=OperationType.INPUT,
-            result=self.ks1.item
+            result=self.ks1
        )
        self.operation2 = self.owned.create_operation(
            alias='2',
            operation_type=OperationType.INPUT,
-            result=self.ks2.item
+            result=self.ks2
        )
        self.operation3 = self.owned.create_operation(
            alias='3',
@ -53,12 +53,12 @@ class TestOssViewset(EndpointTester):
        self.populateData()

        response = self.executeOK(item=self.owned_id)
-        self.assertEqual(response.data['owner'], self.owned.item.owner.pk)
-        self.assertEqual(response.data['title'], self.owned.item.title)
-        self.assertEqual(response.data['alias'], self.owned.item.alias)
-        self.assertEqual(response.data['location'], self.owned.item.location)
-        self.assertEqual(response.data['access_policy'], self.owned.item.access_policy)
-        self.assertEqual(response.data['visible'], self.owned.item.visible)
+        self.assertEqual(response.data['owner'], self.owned.owner.pk)
+        self.assertEqual(response.data['title'], self.owned.title)
+        self.assertEqual(response.data['alias'], self.owned.alias)
+        self.assertEqual(response.data['location'], self.owned.location)
+        self.assertEqual(response.data['access_policy'], self.owned.access_policy)
+        self.assertEqual(response.data['visible'], self.owned.visible)

        self.assertEqual(response.data['item_type'], LibraryItemType.OPERATION_SCHEMA)

@ -179,7 +179,7 @@ class TestOssViewset(EndpointTester):
            'arguments': [self.operation1.pk, self.operation3.pk]
        }
        response = self.executeCreated(data=data, item=self.owned_id)
-        self.owned.item.refresh_from_db()
+        self.owned.refresh_from_db()
        new_operation = response.data['new_operation']
        arguments = self.owned.arguments()
        self.assertTrue(arguments.filter(operation__id=new_operation['id'], argument=self.operation1))
@ -193,14 +193,14 @@ class TestOssViewset(EndpointTester):
            'item_data': {
                'alias': 'Test4',
                'operation_type': OperationType.INPUT,
-                'result': self.ks1.item.pk
+                'result': self.ks1.pk
            },
            'positions': [],
        }
        response = self.executeCreated(data=data, item=self.owned_id)
-        self.owned.item.refresh_from_db()
+        self.owned.refresh_from_db()
        new_operation = response.data['new_operation']
-        self.assertEqual(new_operation['result'], self.ks1.item.pk)
+        self.assertEqual(new_operation['result'], self.ks1.pk)


    @decl_endpoint('/api/oss/{item}/delete-operation', method='patch')
--- a/rsconcept/backend/apps/oss/views/oss.py
+++ b/rsconcept/backend/apps/oss/views/oss.py
@ -20,11 +20,11 @@ from .. import serializers as s
@extend_schema_view()
 class OssViewSet(viewsets.GenericViewSet, generics.ListAPIView, generics.RetrieveAPIView):
    ''' Endpoint: OperationSchema. '''
-    queryset = m.LibraryItem.objects.filter(item_type=m.LibraryItemType.OPERATION_SCHEMA)
+    queryset = m.OperationSchema.objects.all()
    serializer_class = s.LibraryItemSerializer

    def _get_schema(self) -> m.OperationSchema:
-        return m.OperationSchema(cast(m.LibraryItem, self.get_object()))
+        return cast(m.OperationSchema, self.get_object())

    def get_permissions(self):
        ''' Determine permission class. '''
@ -52,7 +52,7 @@ class OssViewSet(viewsets.GenericViewSet, generics.ListAPIView, generics.Retriev
    @action(detail=True, methods=['get'], url_path='details')
    def details(self, request: Request, pk):
        ''' Endpoint: Detailed OSS data. '''
-        serializer = s.OperationSchemaSerializer(cast(m.LibraryItem, self.get_object()))
+        serializer = s.OperationSchemaSerializer(self._get_schema())
        return Response(
            status=c.HTTP_200_OK,
            data=serializer.data
@ -101,13 +101,13 @@ class OssViewSet(viewsets.GenericViewSet, generics.ListAPIView, generics.Retriev
            if new_operation.operation_type != m.OperationType.INPUT and 'arguments' in serializer.validated_data:
                for argument in serializer.validated_data['arguments']:
                    schema.add_argument(operation=new_operation, argument=argument)
-            schema.item.refresh_from_db()
+            schema.refresh_from_db()

        response = Response(
            status=c.HTTP_201_CREATED,
            data={
                'new_operation': s.OperationSerializer(new_operation).data,
-                'oss': s.OperationSchemaSerializer(schema.item).data
+                'oss': s.OperationSchemaSerializer(schema).data
            }
        )
        return response
@ -129,16 +129,16 @@ class OssViewSet(viewsets.GenericViewSet, generics.ListAPIView, generics.Retriev
        schema = self._get_schema()
        serializer = s.OperationDeleteSerializer(
            data=request.data,
-            context={'oss': schema.item}
+            context={'oss': schema}
        )
        serializer.is_valid(raise_exception=True)

        with transaction.atomic():
            schema.update_positions(serializer.validated_data['positions'])
            schema.delete_operation(serializer.validated_data['target'])
-            schema.item.refresh_from_db()
+            schema.refresh_from_db()

        return Response(
            status=c.HTTP_200_OK,
-            data=s.OperationSchemaSerializer(schema.item).data
+            data=s.OperationSchemaSerializer(schema).data
        )
--- a/rsconcept/backend/apps/rsform/migrations/0009_rsform_alter_constituenta_schema_and_more.py
+++ b/rsconcept/backend/apps/rsform/migrations/0009_rsform_alter_constituenta_schema_and_more.py
@ -0,0 +1,35 @@
+# Generated by Django 5.0.7 on 2024-07-22 14:21
+
+import django.db.models.deletion
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('rsform', '0008_alter_libraryitem_item_type'),
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name='RSForm',
+            fields=[
+            ],
+            options={
+                'proxy': True,
+                'indexes': [],
+                'constraints': [],
+            },
+            bases=('rsform.libraryitem',),
+        ),
+        migrations.AlterField(
+            model_name='constituenta',
+            name='schema',
+            field=models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, to='rsform.rsform', verbose_name='Концептуальная схема'),
+        ),
+        migrations.AlterField(
+            model_name='librarytemplate',
+            name='lib_source',
+            field=models.ForeignKey(null=True, on_delete=django.db.models.deletion.CASCADE, to='rsform.rsform', verbose_name='Источник'),
+        ),
+    ]
--- a/rsconcept/backend/apps/rsform/models/Constituenta.py
+++ b/rsconcept/backend/apps/rsform/models/Constituenta.py
@ -40,7 +40,7 @@ class Constituenta(Model):
    ''' Constituenta is the base unit for every conceptual schema. '''
    schema: ForeignKey = ForeignKey(
        verbose_name='Концептуальная схема',
-        to='rsform.LibraryItem',
+        to='rsform.RSForm',
        on_delete=CASCADE
    )
    order: PositiveIntegerField = PositiveIntegerField(
--- a/rsconcept/backend/apps/rsform/models/LibraryTemplate.py
+++ b/rsconcept/backend/apps/rsform/models/LibraryTemplate.py
@ -6,7 +6,7 @@ class LibraryTemplate(Model):
    ''' Template for library items and constituents. '''
    lib_source: ForeignKey = ForeignKey(
        verbose_name='Источник',
-        to='rsform.LibraryItem',
+        to='rsform.RSForm',
        on_delete=CASCADE,
        null=True
    )
--- a/rsconcept/backend/apps/rsform/models/api_RSForm.py
+++ b/rsconcept/backend/apps/rsform/models/api_RSForm.py
@ -5,7 +5,7 @@ from typing import Optional, cast
 from cctext import Entity, Resolver, TermForm, extract_entities, split_grams
 from django.core.exceptions import ValidationError
 from django.db import transaction
-from django.db.models import QuerySet
+from django.db.models import Manager, QuerySet

 from shared import messages as msg

@ -28,21 +28,29 @@ from .Version import Version
 _INSERT_LAST: int = -1


-class RSForm:
+class RSForm(LibraryItem):
    ''' RSForm is math form of conceptual schema. '''

-    def __init__(self, item: LibraryItem):
-        if item.item_type != LibraryItemType.RSFORM:
-            raise ValueError(msg.libraryTypeUnexpected())
-        self.item = item
+    class Meta:
+        ''' Model metadata. '''
+        proxy = True

-    @staticmethod
-    def create(**kwargs) -> 'RSForm':
-        return RSForm(LibraryItem.objects.create(item_type=LibraryItemType.RSFORM, **kwargs))
+    class InternalManager(Manager):
+        ''' Object manager. '''
+
+        def get_queryset(self) -> QuerySet:
+            return super().get_queryset().filter(item_type=LibraryItemType.RSFORM)
+
+        def create(self, **kwargs):
+            kwargs.update({'item_type': LibraryItemType.RSFORM})
+            return super().create(**kwargs)
+
+    # Legit overriding object manager
+    objects = InternalManager()  # type: ignore[misc]

    def constituents(self) -> QuerySet[Constituenta]:
        ''' Get QuerySet containing all constituents of current RSForm. '''
-        return Constituenta.objects.filter(schema=self.item)
+        return Constituenta.objects.filter(schema=self.pk)

    def resolver(self) -> Resolver:
        ''' Create resolver for text references based on schema terms. '''
@ -98,7 +106,7 @@ class RSForm:
        ''' Get maximum alias index for specific CstType. '''
        result: int = 0
        items = Constituenta.objects \
-            .filter(schema=self.item, cst_type=cst_type) \
+            .filter(schema=self, cst_type=cst_type) \
            .order_by('-alias') \
            .values_list('alias', flat=True)
        for alias in items:
@ -150,13 +158,13 @@ class RSForm:
            cst_type = guess_type(alias)
        self._shift_positions(position, 1)
        result = Constituenta.objects.create(
-            schema=self.item,
+            schema=self,
            order=position,
            alias=alias,
            cst_type=cst_type,
            **kwargs
        )
-        self.item.save()
+        self.save()
        result.refresh_from_db()
        return result

@ -183,13 +191,13 @@ class RSForm:
        result = deepcopy(items)
        for cst in result:
            cst.pk = None
-            cst.schema = self.item
+            cst.schema = self
            cst.order = position
            cst.alias = mapping[cst.alias]
            cst.apply_mapping(mapping)
            cst.save()
            position = position + 1
-        self.item.save()
+        self.save()
        return result

    @transaction.atomic
@ -213,7 +221,7 @@ class RSForm:
                count_moved += 1
            update_list.append(cst)
        Constituenta.objects.bulk_update(update_list, ['order'])
-        self.item.save()
+        self.save()

    @transaction.atomic
    def delete_cst(self, listCst):
@ -222,7 +230,7 @@ class RSForm:
            cst.delete()
        self._reset_order()
        self.resolve_all_text()
-        self.item.save()
+        self.save()

    @transaction.atomic
    def substitute(
@ -296,7 +304,7 @@ class RSForm:
    def create_version(self, version: str, description: str, data) -> Version:
        ''' Creates version for current state. '''
        return Version.objects.create(
-            item=self.item,
+            item=self,
            version=version,
            description=description,
            data=data
@ -322,7 +330,7 @@ class RSForm:
        prefix = get_type_prefix(cst_type)
        for text in expressions:
            new_item = Constituenta.objects.create(
-                schema=self.item,
+                schema=self,
                order=position,
                alias=f'{prefix}{free_index}',
                definition_formal=text,
@ -332,7 +340,7 @@ class RSForm:
            free_index = free_index + 1
            position = position + 1

-        self.item.save()
+        self.save()
        return result

    def _shift_positions(self, start: int, shift: int):
@ -341,7 +349,7 @@ class RSForm:
        update_list = \
            Constituenta.objects \
            .only('id', 'order', 'schema') \
-            .filter(schema=self.item, order__gte=start)
+            .filter(schema=self.pk, order__gte=start)
        for cst in update_list:
            cst.order += shift
        Constituenta.objects.bulk_update(update_list, ['order'])
--- a/rsconcept/backend/apps/rsform/models/init.py
+++ b/rsconcept/backend/apps/rsform/models/init.py
@ -1,6 +1,6 @@
 ''' Django: Models. '''

-from .api_RSForm import RSForm
+from .RSForm import RSForm
 from .Constituenta import Constituenta, CstType, _empty_forms
 from .Editor import Editor
 from .LibraryItem import (
--- a/rsconcept/backend/apps/rsform/serializers/data_access.py
+++ b/rsconcept/backend/apps/rsform/serializers/data_access.py
@ -109,22 +109,21 @@ class CstSerializer(serializers.ModelSerializer):

    def update(self, instance: Constituenta, validated_data) -> Constituenta:
        data = validated_data  # Note: use alias for better code readability
-        schema = RSForm(instance.schema)
        definition: Optional[str] = data['definition_raw'] if 'definition_raw' in data else None
        term: Optional[str] = data['term_raw'] if 'term_raw' in data else None
        term_changed = 'term_forms' in data
        if definition is not None and definition != instance.definition_raw:
-            data['definition_resolved'] = schema.resolver().resolve(definition)
+            data['definition_resolved'] = instance.schema.resolver().resolve(definition)
        if term is not None and term != instance.term_raw:
-            data['term_resolved'] = schema.resolver().resolve(term)
+            data['term_resolved'] = instance.schema.resolver().resolve(term)
            if data['term_resolved'] != instance.term_resolved and 'term_forms' not in data:
                data['term_forms'] = []
            term_changed = data['term_resolved'] != instance.term_resolved
        result: Constituenta = super().update(instance, data)
        if term_changed:
-            schema.on_term_change([result.id])
+            instance.schema.on_term_change([result.id])
            result.refresh_from_db()
-        schema.item.save()
+        instance.schema.save()
        return result


@ -170,17 +169,16 @@ class RSFormSerializer(serializers.ModelSerializer):
        model = LibraryItem
        fields = '__all__'

-    def to_representation(self, instance: LibraryItem) -> dict:
+    def to_representation(self, instance: RSForm) -> dict:
        result = LibraryItemDetailsSerializer(instance).data
-        schema = RSForm(instance)
        result['items'] = []
-        for cst in schema.constituents().order_by('order'):
+        for cst in instance.constituents().order_by('order'):
            result['items'].append(CstSerializer(cst).data)
        return result

    def to_versioned_data(self) -> dict:
        ''' Create serializable version representation without redundant data. '''
-        result = self.to_representation(cast(LibraryItem, self.instance))
+        result = self.to_representation(cast(RSForm, self.instance))
        del result['versions']
        del result['subscribers']
        del result['editors']
@ -197,14 +195,14 @@ class RSFormSerializer(serializers.ModelSerializer):

    def from_versioned_data(self, version: int, data: dict) -> dict:
        ''' Load data from version. '''
-        result = self.to_representation(cast(LibraryItem, self.instance))
+        result = self.to_representation(cast(RSForm, self.instance))
        result['version'] = version
        return result | data

    @transaction.atomic
    def restore_from_version(self, data: dict):
        ''' Load data from version. '''
-        schema = RSForm(cast(LibraryItem, self.instance))
+        schema = cast(RSForm, self.instance)
        items: list[dict] = data['items']
        ids: list[int] = [item['id'] for item in items]
        processed: list[int] = []
@ -258,13 +256,13 @@ class RSFormParseSerializer(serializers.ModelSerializer):
        model = LibraryItem
        fields = '__all__'

-    def to_representation(self, instance: LibraryItem):
+    def to_representation(self, instance: RSForm):
        result = RSFormSerializer(instance).data
        return self._parse_data(result)

    def from_versioned_data(self, version: int, data: dict) -> dict:
        ''' Load data from version and parse. '''
-        item = cast(LibraryItem, self.instance)
+        item = cast(RSForm, self.instance)
        result = RSFormSerializer(item).from_versioned_data(version, data)
        return self._parse_data(result)

@ -283,7 +281,7 @@ class CstTargetSerializer(serializers.Serializer):
    target = PKField(many=False, queryset=Constituenta.objects.all())

    def validate(self, attrs):
-        schema = cast(LibraryItem, self.context['schema'])
+        schema = cast(RSForm, self.context['schema'])
        cst = cast(Constituenta, attrs['target'])
        if schema and cst.schema != schema:
            raise serializers.ValidationError({
@ -315,7 +313,7 @@ class CstRenameSerializer(serializers.Serializer):

    def validate(self, attrs):
        attrs = super().validate(attrs)
-        schema = cast(LibraryItem, self.context['schema'])
+        schema = cast(RSForm, self.context['schema'])
        cst = cast(Constituenta, attrs['target'])
        if cst.schema != schema:
            raise serializers.ValidationError({
@ -326,7 +324,7 @@ class CstRenameSerializer(serializers.Serializer):
            raise serializers.ValidationError({
                'alias': msg.renameTrivial(new_alias)
            })
-        if RSForm(schema).constituents().filter(alias=new_alias).exists():
+        if schema.constituents().filter(alias=new_alias).exists():
            raise serializers.ValidationError({
                'alias': msg.aliasTaken(new_alias)
            })
@ -338,7 +336,7 @@ class CstListSerializer(serializers.Serializer):
    items = PKField(many=True, queryset=Constituenta.objects.all())

    def validate(self, attrs):
-        schema = cast(LibraryItem, self.context['schema'])
+        schema = cast(RSForm, self.context['schema'])
        if not schema:
            return attrs

@ -370,7 +368,7 @@ class CstSubstituteSerializer(serializers.Serializer):
    )

    def validate(self, attrs):
-        schema = cast(LibraryItem, self.context['schema'])
+        schema = cast(RSForm, self.context['schema'])
        deleted = set()
        for item in attrs['substitutions']:
            original_cst = cast(Constituenta, item['original'])
@ -397,8 +395,8 @@ class CstSubstituteSerializer(serializers.Serializer):

 class InlineSynthesisSerializer(serializers.Serializer):
    ''' Serializer: Inline synthesis operation input. '''
-    receiver = PKField(many=False, queryset=LibraryItem.objects.all())
-    source = PKField(many=False, queryset=LibraryItem.objects.all())  # type: ignore
+    receiver = PKField(many=False, queryset=RSForm.objects.all())
+    source = PKField(many=False, queryset=RSForm.objects.all())  # type: ignore
    items = PKField(many=True, queryset=Constituenta.objects.all())
    substitutions = serializers.ListField(
        child=CstSubstituteSerializerBase()
@ -406,8 +404,8 @@ class InlineSynthesisSerializer(serializers.Serializer):

    def validate(self, attrs):
        user = cast(User, self.context['user'])
-        schema_in = cast(LibraryItem, attrs['source'])
-        schema_out = cast(LibraryItem, attrs['receiver'])
+        schema_in = cast(RSForm, attrs['source'])
+        schema_out = cast(RSForm, attrs['receiver'])
        if user.is_anonymous or (schema_out.owner != user and not user.is_staff):
            raise PermissionDenied({
                'message': msg.schemaNotOwned(),
--- a/rsconcept/backend/apps/rsform/serializers/io_files.py
+++ b/rsconcept/backend/apps/rsform/serializers/io_files.py
@ -39,9 +39,9 @@ class RSFormTRSSerializer(serializers.Serializer):
    def _prepare_json_rsform(schema: RSForm) -> dict:
        return {
            'type': _TRS_TYPE,
-            'title': schema.item.title,
-            'alias': schema.item.alias,
-            'comment': schema.item.comment,
+            'title': schema.title,
+            'alias': schema.alias,
+            'comment': schema.comment,
            'items': [],
            'claimed': False,
            'selection': [],
@ -125,7 +125,7 @@ class RSFormTRSSerializer(serializers.Serializer):
            result['comment'] = data.get('comment', '')
        if 'id' in data:
            result['id'] = data['id']
-            self.instance = RSForm(LibraryItem.objects.get(pk=result['id']))
+            self.instance = RSForm.objects.get(pk=result['id'])
        return result

    def validate(self, attrs: dict):
@ -139,7 +139,7 @@ class RSFormTRSSerializer(serializers.Serializer):

    @transaction.atomic
    def create(self, validated_data: dict) -> RSForm:
-        self.instance: RSForm = RSForm.create(
+        self.instance: RSForm = RSForm.objects.create(
            owner=validated_data.get('owner', None),
            alias=validated_data['alias'],
            title=validated_data['title'],
@ -149,12 +149,12 @@ class RSFormTRSSerializer(serializers.Serializer):
            access_policy=validated_data['access_policy'],
            location=validated_data['location']
        )
-        self.instance.item.save()
+        self.instance.save()
        order = 1
        for cst_data in validated_data['items']:
            cst = Constituenta(
                alias=cst_data['alias'],
-                schema=self.instance.item,
+                schema=self.instance,
                order=order,
                cst_type=cst_data['cstType'],
            )
@ -167,11 +167,11 @@ class RSFormTRSSerializer(serializers.Serializer):
    @transaction.atomic
    def update(self, instance: RSForm, validated_data) -> RSForm:
        if 'alias' in validated_data:
-            instance.item.alias = validated_data['alias']
+            instance.alias = validated_data['alias']
        if 'title' in validated_data:
-            instance.item.title = validated_data['title']
+            instance.title = validated_data['title']
        if 'comment' in validated_data:
-            instance.item.comment = validated_data['comment']
+            instance.comment = validated_data['comment']

        order = 1
        prev_constituents = instance.constituents()
@ -188,7 +188,7 @@ class RSFormTRSSerializer(serializers.Serializer):
            else:
                cst = Constituenta(
                    alias=cst_data['alias'],
-                    schema=instance.item,
+                    schema=instance,
                    order=order,
                    cst_type=cst_data['cstType'],
                )
@ -202,7 +202,7 @@ class RSFormTRSSerializer(serializers.Serializer):
                prev_cst.delete()

        instance.resolve_all_text()
-        instance.item.save()
+        instance.save()
        return instance

    @staticmethod
--- a/rsconcept/backend/apps/rsform/tests/s_models/t_Constituenta.py
+++ b/rsconcept/backend/apps/rsform/tests/s_models/t_Constituenta.py
@ -3,15 +3,15 @@ from django.db.utils import IntegrityError
 from django.forms import ValidationError
 from django.test import TestCase

-from apps.rsform.models import Constituenta, CstType, LibraryItem, LibraryItemType
+from apps.rsform.models import Constituenta, CstType, LibraryItemType, RSForm


 class TestConstituenta(TestCase):
    ''' Testing Constituenta model. '''

    def setUp(self):
-        self.schema1 = LibraryItem.objects.create(item_type=LibraryItemType.RSFORM, title='Test1')
-        self.schema2 = LibraryItem.objects.create(item_type=LibraryItemType.RSFORM, title='Test2')
+        self.schema1 = RSForm.objects.create(title='Test1')
+        self.schema2 = RSForm.objects.create(title='Test2')


    def test_str(self):
--- a/rsconcept/backend/apps/rsform/tests/s_models/t_Editor.py
+++ b/rsconcept/backend/apps/rsform/tests/s_models/t_Editor.py
@ -1,7 +1,7 @@
 ''' Testing models: Editor. '''
 from django.test import TestCase

-from apps.rsform.models import Editor, LibraryItem, LibraryItemType, User
+from apps.rsform.models import Editor, LibraryItemType, RSForm, User


 class TestEditor(TestCase):
@ -10,8 +10,7 @@ class TestEditor(TestCase):
    def setUp(self):
        self.user1 = User.objects.create(username='User1')
        self.user2 = User.objects.create(username='User2')
-        self.item = LibraryItem.objects.create(
-            item_type=LibraryItemType.RSFORM,
+        self.item = RSForm.objects.create(
            title='Test',
            alias='КС1',
            owner=self.user1
--- a/rsconcept/backend/apps/rsform/tests/s_models/t_RSForm.py
+++ b/rsconcept/backend/apps/rsform/tests/s_models/t_RSForm.py
@ -11,49 +11,49 @@ class TestRSForm(TestCase):
    def setUp(self):
        self.user1 = User.objects.create(username='User1')
        self.user2 = User.objects.create(username='User2')
-        self.schema = RSForm.create(title='Test')
+        self.schema = RSForm.objects.create(title='Test')
        self.assertNotEqual(self.user1, self.user2)


    def test_constituents(self):
-        schema1 = RSForm.create(title='Test1')
-        schema2 = RSForm.create(title='Test2')
+        schema1 = RSForm.objects.create(title='Test1')
+        schema2 = RSForm.objects.create(title='Test2')
        self.assertFalse(schema1.constituents().exists())
        self.assertFalse(schema2.constituents().exists())

-        Constituenta.objects.create(alias='X1', schema=schema1.item, order=1)
-        Constituenta.objects.create(alias='X2', schema=schema1.item, order=2)
+        Constituenta.objects.create(alias='X1', schema=schema1, order=1)
+        Constituenta.objects.create(alias='X2', schema=schema1, order=2)
        self.assertTrue(schema1.constituents().exists())
        self.assertFalse(schema2.constituents().exists())
        self.assertEqual(schema1.constituents().count(), 2)


    def test_get_max_index(self):
-        schema1 = RSForm.create(title='Test1')
-        Constituenta.objects.create(alias='X1', schema=schema1.item, order=1)
-        Constituenta.objects.create(alias='D2', cst_type=CstType.TERM, schema=schema1.item, order=2)
+        schema1 = RSForm.objects.create(title='Test1')
+        Constituenta.objects.create(alias='X1', schema=schema1, order=1)
+        Constituenta.objects.create(alias='D2', cst_type=CstType.TERM, schema=schema1, order=2)
        self.assertEqual(schema1.get_max_index(CstType.BASE), 1)
        self.assertEqual(schema1.get_max_index(CstType.TERM), 2)
        self.assertEqual(schema1.get_max_index(CstType.AXIOM), 0)


    def test_insert_at(self):
-        schema = RSForm.create(title='Test')
+        schema = RSForm.objects.create(title='Test')
        x1 = schema.insert_new('X1')
        self.assertEqual(x1.order, 1)
-        self.assertEqual(x1.schema, schema.item)
+        self.assertEqual(x1.schema, schema)

        x2 = schema.insert_new('X2', position=1)
        x1.refresh_from_db()
        self.assertEqual(x2.order, 1)
-        self.assertEqual(x2.schema, schema.item)
+        self.assertEqual(x2.schema, schema)
        self.assertEqual(x1.order, 2)

        x3 = schema.insert_new('X3', position=4)
        x2.refresh_from_db()
        x1.refresh_from_db()
        self.assertEqual(x3.order, 3)
-        self.assertEqual(x3.schema, schema.item)
+        self.assertEqual(x3.schema, schema)
        self.assertEqual(x2.order, 1)
        self.assertEqual(x1.order, 2)

@ -62,7 +62,7 @@ class TestRSForm(TestCase):
        x2.refresh_from_db()
        x1.refresh_from_db()
        self.assertEqual(x4.order, 3)
-        self.assertEqual(x4.schema, schema.item)
+        self.assertEqual(x4.schema, schema)
        self.assertEqual(x3.order, 4)
        self.assertEqual(x2.order, 1)
        self.assertEqual(x1.order, 2)
@ -94,11 +94,11 @@ class TestRSForm(TestCase):
    def test_insert_last(self):
        x1 = self.schema.insert_new('X1')
        self.assertEqual(x1.order, 1)
-        self.assertEqual(x1.schema, self.schema.item)
+        self.assertEqual(x1.schema, self.schema)

        x2 = self.schema.insert_new('X2')
        self.assertEqual(x2.order, 2)
-        self.assertEqual(x2.schema, self.schema.item)
+        self.assertEqual(x2.schema, self.schema)
        self.assertEqual(x1.order, 1)

    def test_create_cst(self):
--- a/rsconcept/backend/apps/rsform/tests/s_views/t_constituents.py
+++ b/rsconcept/backend/apps/rsform/tests/s_views/t_constituents.py
@ -8,12 +8,12 @@ class TestConstituentaAPI(EndpointTester):

    def setUp(self):
        super().setUp()
-        self.rsform_owned = RSForm.create(title='Test', alias='T1', owner=self.user)
-        self.rsform_unowned = RSForm.create(title='Test2', alias='T2')
+        self.rsform_owned = RSForm.objects.create(title='Test', alias='T1', owner=self.user)
+        self.rsform_unowned = RSForm.objects.create(title='Test2', alias='T2')
        self.cst1 = Constituenta.objects.create(
            alias='X1',
            cst_type=CstType.BASE,
-            schema=self.rsform_owned.item,
+            schema=self.rsform_owned,
            order=1,
            convention='Test',
            term_raw='Test1',
@ -22,7 +22,7 @@ class TestConstituentaAPI(EndpointTester):
        self.cst2 = Constituenta.objects.create(
            alias='X2',
            cst_type=CstType.BASE,
-            schema=self.rsform_unowned.item,
+            schema=self.rsform_unowned,
            order=1,
            convention='Test1',
            term_raw='Test2',
@ -30,7 +30,7 @@ class TestConstituentaAPI(EndpointTester):
        )
        self.cst3 = Constituenta.objects.create(
            alias='X3',
-            schema=self.rsform_owned.item,
+            schema=self.rsform_owned,
            order=2,
            term_raw='Test3',
            term_resolved='Test3',
--- a/rsconcept/backend/apps/rsform/tests/s_views/t_library.py
+++ b/rsconcept/backend/apps/rsform/tests/s_views/t_library.py
@ -20,20 +20,16 @@ class TestLibraryViewset(EndpointTester):

    def setUp(self):
        super().setUp()
-        self.owned = LibraryItem.objects.create(
-            item_type=LibraryItemType.RSFORM,
+        self.owned = RSForm.objects.create(
            title='Test',
            alias='T1',
            owner=self.user
        )
-        self.schema = RSForm(self.owned)
-        self.unowned = LibraryItem.objects.create(
-            item_type=LibraryItemType.RSFORM,
+        self.unowned = RSForm.objects.create(
            title='Test2',
            alias='T2'
        )
-        self.common = LibraryItem.objects.create(
-            item_type=LibraryItemType.RSFORM,
+        self.common = RSForm.objects.create(
            title='Test3',
            alias='T3',
            location=LocationHead.COMMON
@ -363,12 +359,12 @@ class TestLibraryViewset(EndpointTester):

    @decl_endpoint('/api/library/{item}/clone', method='post')
    def test_clone_rsform(self):
-        x12 = self.schema.insert_new(
+        x12 = self.owned.insert_new(
            alias='X12',
            term_raw='человек',
            term_resolved='человек'
        )
-        d2 = self.schema.insert_new(
+        d2 = self.owned.insert_new(
            alias='D2',
            term_raw='@{X12|plur}',
            term_resolved='люди'
--- a/rsconcept/backend/apps/rsform/tests/s_views/t_operations.py
+++ b/rsconcept/backend/apps/rsform/tests/s_views/t_operations.py
@ -10,16 +10,16 @@ class TestInlineSynthesis(EndpointTester):
    @decl_endpoint('/api/operations/inline-synthesis', method='patch')
    def setUp(self):
        super().setUp()
-        self.schema1 = RSForm.create(title='Test1', alias='T1', owner=self.user)
-        self.schema2 = RSForm.create(title='Test2', alias='T2', owner=self.user)
-        self.unowned = RSForm.create(title='Test3', alias='T3')
+        self.schema1 = RSForm.objects.create(title='Test1', alias='T1', owner=self.user)
+        self.schema2 = RSForm.objects.create(title='Test2', alias='T2', owner=self.user)
+        self.unowned = RSForm.objects.create(title='Test3', alias='T3')


    def test_inline_synthesis_inputs(self):
        invalid_id = 1338
        data = {
-            'receiver': self.unowned.item.pk,
-            'source': self.schema1.item.pk,
+            'receiver': self.unowned.pk,
+            'source': self.schema1.pk,
            'items': [],
            'substitutions': []
        }
@ -28,11 +28,11 @@ class TestInlineSynthesis(EndpointTester):
        data['receiver'] = invalid_id
        self.executeBadData(data=data)

-        data['receiver'] = self.schema1.item.pk
+        data['receiver'] = self.schema1.pk
        data['source'] = invalid_id
        self.executeBadData(data=data)

-        data['source'] = self.schema1.item.pk
+        data['source'] = self.schema1.pk
        self.executeOK(data=data)

        data['items'] = [invalid_id]
@ -51,8 +51,8 @@ class TestInlineSynthesis(EndpointTester):
        ks2_a1 = self.schema2.insert_new('A1', definition_formal='1=1')  # -> not included in items

        data = {
-            'receiver': self.schema1.item.pk,
-            'source': self.schema2.item.pk,
+            'receiver': self.schema1.pk,
+            'source': self.schema2.pk,
            'items': [ks2_x1.pk, ks2_x2.pk, ks2_s1.pk, ks2_d1.pk],
            'substitutions': [
                {
--- a/rsconcept/backend/apps/rsform/tests/s_views/t_rsforms.py
+++ b/rsconcept/backend/apps/rsform/tests/s_views/t_rsforms.py
@ -24,12 +24,12 @@ class TestRSFormViewset(EndpointTester):

    def setUp(self):
        super().setUp()
-        self.owned = RSForm.create(title='Test', alias='T1', owner=self.user)
-        self.owned_id = self.owned.item.pk
-        self.unowned = RSForm.create(title='Test2', alias='T2')
-        self.unowned_id = self.unowned.item.pk
-        self.private = RSForm.create(title='Test2', alias='T2', access_policy=AccessPolicy.PRIVATE)
-        self.private_id = self.private.item.pk
+        self.owned = RSForm.objects.create(title='Test', alias='T1', owner=self.user)
+        self.owned_id = self.owned.pk
+        self.unowned = RSForm.objects.create(title='Test2', alias='T2')
+        self.unowned_id = self.unowned.pk
+        self.private = RSForm.objects.create(title='Test2', alias='T2', access_policy=AccessPolicy.PRIVATE)
+        self.private_id = self.private.pk


    @decl_endpoint('/api/rsforms/create-detailed', method='post')
@ -63,19 +63,19 @@ class TestRSFormViewset(EndpointTester):
        )
        response = self.executeOK()
        self.assertFalse(response_contains(response, non_schema))
-        self.assertTrue(response_contains(response, self.unowned.item))
-        self.assertTrue(response_contains(response, self.owned.item))
+        self.assertTrue(response_contains(response, self.unowned))
+        self.assertTrue(response_contains(response, self.owned))


    @decl_endpoint('/api/rsforms/{item}/contents', method='get')
    def test_contents(self):
        response = self.executeOK(item=self.owned_id)
-        self.assertEqual(response.data['owner'], self.owned.item.owner.pk)
-        self.assertEqual(response.data['title'], self.owned.item.title)
-        self.assertEqual(response.data['alias'], self.owned.item.alias)
-        self.assertEqual(response.data['location'], self.owned.item.location)
-        self.assertEqual(response.data['access_policy'], self.owned.item.access_policy)
-        self.assertEqual(response.data['visible'], self.owned.item.visible)
+        self.assertEqual(response.data['owner'], self.owned.owner.pk)
+        self.assertEqual(response.data['title'], self.owned.title)
+        self.assertEqual(response.data['alias'], self.owned.alias)
+        self.assertEqual(response.data['location'], self.owned.location)
+        self.assertEqual(response.data['access_policy'], self.owned.access_policy)
+        self.assertEqual(response.data['visible'], self.owned.visible)


    @decl_endpoint('/api/rsforms/{item}/details', method='get')
@ -92,12 +92,12 @@ class TestRSFormViewset(EndpointTester):
        )

        response = self.executeOK(item=self.owned_id)
-        self.assertEqual(response.data['owner'], self.owned.item.owner.pk)
-        self.assertEqual(response.data['title'], self.owned.item.title)
-        self.assertEqual(response.data['alias'], self.owned.item.alias)
-        self.assertEqual(response.data['location'], self.owned.item.location)
-        self.assertEqual(response.data['access_policy'], self.owned.item.access_policy)
-        self.assertEqual(response.data['visible'], self.owned.item.visible)
+        self.assertEqual(response.data['owner'], self.owned.owner.pk)
+        self.assertEqual(response.data['title'], self.owned.title)
+        self.assertEqual(response.data['alias'], self.owned.alias)
+        self.assertEqual(response.data['location'], self.owned.location)
+        self.assertEqual(response.data['access_policy'], self.owned.access_policy)
+        self.assertEqual(response.data['visible'], self.owned.visible)

        self.assertEqual(len(response.data['items']), 2)
        self.assertEqual(response.data['items'][0]['id'], x1.pk)
@ -176,9 +176,9 @@ class TestRSFormViewset(EndpointTester):

    @decl_endpoint('/api/rsforms/{item}/export-trs', method='get')
    def test_export_trs(self):
-        schema = RSForm.create(title='Test')
+        schema = RSForm.objects.create(title='Test')
        schema.insert_new('X1')
-        response = self.executeOK(item=schema.item.pk)
+        response = self.executeOK(item=schema.pk)
        self.assertEqual(response.headers['Content-Disposition'], 'attachment; filename=Schema.trs')
        with io.BytesIO(response.content) as stream:
            with ZipFile(stream, 'r') as zipped_file:
@ -387,7 +387,7 @@ class TestRSFormViewset(EndpointTester):
        data = {'items': [x1.pk]}
        response = self.executeOK(data=data)
        x2.refresh_from_db()
-        self.owned.item.refresh_from_db()
+        self.owned.refresh_from_db()
        self.assertEqual(len(response.data['items']), 1)
        self.assertEqual(self.owned.constituents().count(), 1)
        self.assertEqual(x2.alias, 'X2')
@ -449,16 +449,16 @@ class TestRSFormViewset(EndpointTester):
    @decl_endpoint('/api/rsforms/{item}/load-trs', method='patch')
    def test_load_trs(self):
        self.set_params(item=self.owned_id)
-        self.owned.item.title = 'Test11'
-        self.owned.item.save()
+        self.owned.title = 'Test11'
+        self.owned.save()
        x1 = self.owned.insert_new('X1')
        work_dir = os.path.dirname(os.path.abspath(__file__))
        with open(f'{work_dir}/data/sample-rsform.trs', 'rb') as file:
            data = {'file': file, 'load_metadata': False}
            response = self.client.patch(self.endpoint, data=data, format='multipart')
-        self.owned.item.refresh_from_db()
+        self.owned.refresh_from_db()
        self.assertEqual(response.status_code, status.HTTP_200_OK)
-        self.assertEqual(self.owned.item.title, 'Test11')
+        self.assertEqual(self.owned.title, 'Test11')
        self.assertEqual(len(response.data['items']), 25)
        self.assertEqual(self.owned.constituents().count(), 25)
        self.assertFalse(Constituenta.objects.filter(pk=x1.pk).exists())
--- a/rsconcept/backend/apps/rsform/tests/s_views/t_versions.py
+++ b/rsconcept/backend/apps/rsform/tests/s_views/t_versions.py
@ -15,10 +15,9 @@ class TestVersionViews(EndpointTester):

    def setUp(self):
        super().setUp()
-        self.owned = RSForm.create(title='Test', alias='T1', owner=self.user).item
-        self.schema = RSForm(self.owned)
-        self.unowned = RSForm.create(title='Test2', alias='T2').item
-        self.x1 = self.schema.insert_new(
+        self.owned = RSForm.objects.create(title='Test', alias='T1', owner=self.user)
+        self.unowned = RSForm.objects.create(title='Test2', alias='T2')
+        self.x1 = self.owned.insert_new(
            alias='X1',
            convention='testStart'
        )
@ -135,14 +134,14 @@ class TestVersionViews(EndpointTester):
    @decl_endpoint('/api/versions/{version}/restore', method='patch')
    def test_restore_version(self):
        x1 = self.x1
-        x2 = self.schema.insert_new('X2')
-        d1 = self.schema.insert_new('D1', term_raw='TestTerm')
+        x2 = self.owned.insert_new('X2')
+        d1 = self.owned.insert_new('D1', term_raw='TestTerm')
        data = {'version': '1.0.0', 'description': 'test'}
        version_id = self._create_version(data=data)
        invalid_id = version_id + 1337

        d1.delete()
-        x3 = self.schema.insert_new('X3')
+        x3 = self.owned.insert_new('X3')
        x1.order = x3.order
        x1.convention = 'Test2'
        x1.term_raw = 'Test'
--- a/rsconcept/backend/apps/rsform/views/library.py
+++ b/rsconcept/backend/apps/rsform/views/library.py
@ -85,7 +85,11 @@ class LibraryViewSet(viewsets.ModelViewSet):
        serializer = s.LibraryItemCloneSerializer(data=request.data)
        serializer.is_valid(raise_exception=True)
        item = self._get_item()
-        clone = deepcopy(item)
+        if item.item_type != m.LibraryItemType.RSFORM:
+            return Response(status=c.HTTP_400_BAD_REQUEST)
+
+        schema = m.RSForm.objects.get(pk=item.pk)
+        clone = deepcopy(schema)
        clone.pk = None
        clone.owner = self.request.user
        clone.title = serializer.validated_data['title']
@ -98,9 +102,8 @@ class LibraryViewSet(viewsets.ModelViewSet):

        with transaction.atomic():
            clone.save()
-            if clone.item_type == m.LibraryItemType.RSFORM:
            need_filter = 'items' in request.data
-                for cst in m.RSForm(item).constituents():
+            for cst in schema.constituents():
                if not need_filter or cst.pk in request.data['items']:
                    cst.pk = None
                    cst.schema = clone
@ -109,7 +112,6 @@ class LibraryViewSet(viewsets.ModelViewSet):
                status=c.HTTP_201_CREATED,
                data=s.RSFormParseSerializer(clone).data
            )
-        return Response(status=c.HTTP_400_BAD_REQUEST)

    @extend_schema(
        summary='subscribe to item',
--- a/rsconcept/backend/apps/rsform/views/operations.py
+++ b/rsconcept/backend/apps/rsform/views/operations.py
@ -27,7 +27,7 @@ def inline_synthesis(request: Request):
    )
    serializer.is_valid(raise_exception=True)

-    schema = m.RSForm(serializer.validated_data['receiver'])
+    schema = cast(m.RSForm, serializer.validated_data['receiver'])
    items = cast(list[m.Constituenta], serializer.validated_data['items'])

    with transaction.atomic():
@ -46,5 +46,5 @@ def inline_synthesis(request: Request):

    return Response(
        status=c.HTTP_200_OK,
-        data=s.RSFormParseSerializer(schema.item).data
+        data=s.RSFormParseSerializer(schema).data
    )
--- a/rsconcept/backend/apps/rsform/views/rsforms.py
+++ b/rsconcept/backend/apps/rsform/views/rsforms.py
@ -25,11 +25,11 @@ from .. import utils
@extend_schema_view()
 class RSFormViewSet(viewsets.GenericViewSet, generics.ListAPIView, generics.RetrieveAPIView):
    ''' Endpoint: RSForm operations. '''
-    queryset = m.LibraryItem.objects.filter(item_type=m.LibraryItemType.RSFORM)
+    queryset = m.RSForm.objects.all()
    serializer_class = s.LibraryItemSerializer

    def _get_schema(self) -> m.RSForm:
-        return m.RSForm(cast(m.LibraryItem, self.get_object()))
+        return cast(m.RSForm, self.get_object())

    def get_permissions(self):
        ''' Determine permission class. '''
@ -81,12 +81,12 @@ class RSFormViewSet(viewsets.GenericViewSet, generics.ListAPIView, generics.Retr
            insert_after = None
        new_cst = schema.create_cst(data, insert_after)

-        schema.item.refresh_from_db()
+        schema.refresh_from_db()
        response = Response(
            status=c.HTTP_201_CREATED,
            data={
                'new_cst': s.CstSerializer(new_cst).data,
-                'schema': s.RSFormParseSerializer(schema.item).data
+                'schema': s.RSFormParseSerializer(schema).data
            }
        )
        response['Location'] = new_cst.get_absolute_url()
@ -108,11 +108,11 @@ class RSFormViewSet(viewsets.GenericViewSet, generics.ListAPIView, generics.Retr
        ''' Produce a term for every element of the target constituenta typification. '''
        schema = self._get_schema()

-        serializer = s.CstTargetSerializer(data=request.data, context={'schema': schema.item})
+        serializer = s.CstTargetSerializer(data=request.data, context={'schema': schema})
        serializer.is_valid(raise_exception=True)
        cst = cast(m.Constituenta, serializer.validated_data['target'])

-        schema_details = s.RSFormParseSerializer(schema.item).data['items']
+        schema_details = s.RSFormParseSerializer(schema).data['items']
        cst_parse = next(item for item in schema_details if item['id'] == cst.id)['parse']
        if not cst_parse['typification']:
            return Response(
@ -125,7 +125,7 @@ class RSFormViewSet(viewsets.GenericViewSet, generics.ListAPIView, generics.Retr
            status=c.HTTP_200_OK,
            data={
                'cst_list': result,
-                'schema': s.RSFormParseSerializer(schema.item).data
+                'schema': s.RSFormParseSerializer(schema).data
            }
        )

@ -144,7 +144,7 @@ class RSFormViewSet(viewsets.GenericViewSet, generics.ListAPIView, generics.Retr
    def cst_rename(self, request: Request, pk):
        ''' Rename constituenta possibly changing type. '''
        schema = self._get_schema()
-        serializer = s.CstRenameSerializer(data=request.data, context={'schema': schema.item})
+        serializer = s.CstRenameSerializer(data=request.data, context={'schema': schema})
        serializer.is_valid(raise_exception=True)

        cst = cast(m.Constituenta, serializer.validated_data['target'])
@ -156,14 +156,14 @@ class RSFormViewSet(viewsets.GenericViewSet, generics.ListAPIView, generics.Retr
        with transaction.atomic():
            cst.save()
            schema.apply_mapping(mapping={old_alias: cst.alias}, change_aliases=False)
-            schema.item.refresh_from_db()
+            schema.refresh_from_db()
            cst.refresh_from_db()

        return Response(
            status=c.HTTP_200_OK,
            data={
                'new_cst': s.CstSerializer(cst).data,
-                'schema': s.RSFormParseSerializer(schema.item).data
+                'schema': s.RSFormParseSerializer(schema).data
            }
        )

@ -184,7 +184,7 @@ class RSFormViewSet(viewsets.GenericViewSet, generics.ListAPIView, generics.Retr
        schema = self._get_schema()
        serializer = s.CstSubstituteSerializer(
            data=request.data,
-            context={'schema': schema.item}
+            context={'schema': schema}
        )
        serializer.is_valid(raise_exception=True)

@ -193,10 +193,10 @@ class RSFormViewSet(viewsets.GenericViewSet, generics.ListAPIView, generics.Retr
                original = cast(m.Constituenta, substitution['original'])
                replacement = cast(m.Constituenta, substitution['substitution'])
                schema.substitute(original, replacement, substitution['transfer_term'])
-            schema.item.refresh_from_db()
+            schema.refresh_from_db()
        return Response(
            status=c.HTTP_200_OK,
-            data=s.RSFormParseSerializer(schema.item).data
+            data=s.RSFormParseSerializer(schema).data
        )

    @extend_schema(
@ -216,14 +216,14 @@ class RSFormViewSet(viewsets.GenericViewSet, generics.ListAPIView, generics.Retr
        schema = self._get_schema()
        serializer = s.CstListSerializer(
            data=request.data,
-            context={'schema': schema.item}
+            context={'schema': schema}
        )
        serializer.is_valid(raise_exception=True)
        schema.delete_cst(serializer.validated_data['items'])
-        schema.item.refresh_from_db()
+        schema.refresh_from_db()
        return Response(
            status=c.HTTP_200_OK,
-            data=s.RSFormParseSerializer(schema.item).data
+            data=s.RSFormParseSerializer(schema).data
        )

    @extend_schema(
@ -243,7 +243,7 @@ class RSFormViewSet(viewsets.GenericViewSet, generics.ListAPIView, generics.Retr
        schema = self._get_schema()
        serializer = s.CstMoveSerializer(
            data=request.data,
-            context={'schema': schema.item}
+            context={'schema': schema}
        )
        serializer.is_valid(raise_exception=True)
        schema.move_cst(
@ -252,7 +252,7 @@ class RSFormViewSet(viewsets.GenericViewSet, generics.ListAPIView, generics.Retr
        )
        return Response(
            status=c.HTTP_200_OK,
-            data=s.RSFormParseSerializer(schema.item).data
+            data=s.RSFormParseSerializer(schema).data
        )

    @extend_schema(
@ -272,7 +272,7 @@ class RSFormViewSet(viewsets.GenericViewSet, generics.ListAPIView, generics.Retr
        schema.reset_aliases()
        return Response(
            status=c.HTTP_200_OK,
-            data=s.RSFormParseSerializer(schema.item).data
+            data=s.RSFormParseSerializer(schema).data
        )

    @extend_schema(
@ -292,7 +292,7 @@ class RSFormViewSet(viewsets.GenericViewSet, generics.ListAPIView, generics.Retr
        schema.restore_order()
        return Response(
            status=c.HTTP_200_OK,
-            data=s.RSFormParseSerializer(schema.item).data
+            data=s.RSFormParseSerializer(schema).data
        )

    @extend_schema(
@ -314,7 +314,7 @@ class RSFormViewSet(viewsets.GenericViewSet, generics.ListAPIView, generics.Retr
        schema = self._get_schema()
        load_metadata = input_serializer.validated_data['load_metadata']
        data = utils.read_zipped_json(request.FILES['file'].file, utils.EXTEOR_INNER_FILENAME)
-        data['id'] = schema.item.pk
+        data['id'] = schema.pk

        serializer = s.RSFormTRSSerializer(
            data=data,
@ -324,7 +324,7 @@ class RSFormViewSet(viewsets.GenericViewSet, generics.ListAPIView, generics.Retr
        result = serializer.save()
        return Response(
            status=c.HTTP_200_OK,
-            data=s.RSFormParseSerializer(result.item).data
+            data=s.RSFormParseSerializer(result).data
        )

    @extend_schema(
@ -357,7 +357,7 @@ class RSFormViewSet(viewsets.GenericViewSet, generics.ListAPIView, generics.Retr
    @action(detail=True, methods=['get'], url_path='details')
    def details(self, request: Request, pk):
        ''' Endpoint: Detailed schema view including statuses and parse. '''
-        serializer = s.RSFormParseSerializer(cast(m.LibraryItem, self.get_object()))
+        serializer = s.RSFormParseSerializer(self._get_schema())
        return Response(
            status=c.HTTP_200_OK,
            data=serializer.data
@ -421,7 +421,7 @@ class RSFormViewSet(viewsets.GenericViewSet, generics.ListAPIView, generics.Retr
        ''' Endpoint: Download Exteor compatible file. '''
        data = s.RSFormTRSSerializer(self._get_schema()).data
        file = utils.write_zipped_json(data, utils.EXTEOR_INNER_FILENAME)
-        filename = utils.filename_for_schema(self._get_schema().item.alias)
+        filename = utils.filename_for_schema(self._get_schema().alias)
        response = HttpResponse(file, content_type='application/zip')
        response['Content-Disposition'] = f'attachment; filename={filename}'
        return response
@ -451,7 +451,7 @@ class TrsImportView(views.APIView):
        )
        serializer.is_valid(raise_exception=True)
        schema = serializer.save()
-        result = s.LibraryItemSerializer(schema.item)
+        result = s.LibraryItemSerializer(schema)
        return Response(
            status=c.HTTP_201_CREATED,
            data=result.data
@ -483,7 +483,7 @@ def create_rsform(request: Request):
        serializer_rsform = s.RSFormTRSSerializer(data=data, context={'load_meta': True})
        serializer_rsform.is_valid(raise_exception=True)
        schema = serializer_rsform.save()
-    result = s.LibraryItemSerializer(schema.item)
+    result = s.LibraryItemSerializer(schema)
    return Response(
        status=c.HTTP_201_CREATED,
        data=result.data
--- a/rsconcept/backend/apps/rsform/views/versions.py
+++ b/rsconcept/backend/apps/rsform/views/versions.py
@ -42,10 +42,11 @@ class VersionViewset(
        ''' Restore version data into current item. '''
        version = cast(m.Version, self.get_object())
        item = cast(m.LibraryItem, version.item)
-        s.RSFormSerializer(item).restore_from_version(version.data)
+        schema = m.RSForm.objects.get(pk=item.pk)
+        s.RSFormSerializer(schema).restore_from_version(version.data)
        return Response(
            status=c.HTTP_200_OK,
-            data=s.RSFormParseSerializer(item).data
+            data=s.RSFormParseSerializer(schema).data
        )


@ -65,7 +66,7 @@ class VersionViewset(
 def create_version(request: Request, pk_item: int):
    ''' Endpoint: Create new version for RSForm copying current content. '''
    try:
-        item = m.LibraryItem.objects.get(pk=pk_item)
+        item = m.RSForm.objects.get(pk=pk_item)
    except m.LibraryItem.DoesNotExist:
        return Response(status=c.HTTP_404_NOT_FOUND)
    creator = request.user
@ -75,7 +76,7 @@ def create_version(request: Request, pk_item: int):
    version_input = s.VersionCreateSerializer(data=request.data)
    version_input.is_valid(raise_exception=True)
    data = s.RSFormSerializer(item).to_versioned_data()
-    result = m.RSForm(item).create_version(
+    result = item.create_version(
        version=version_input.validated_data['version'],
        description=version_input.validated_data['description'],
        data=data
@ -102,8 +103,8 @@ def create_version(request: Request, pk_item: int):
 def retrieve_version(request: Request, pk_item: int, pk_version: int):
    ''' Endpoint: Retrieve version for RSForm. '''
    try:
-        item = m.LibraryItem.objects.get(pk=pk_item)
-    except m.LibraryItem.DoesNotExist:
+        item = m.RSForm.objects.get(pk=pk_item)
+    except m.RSForm.DoesNotExist:
        return Response(status=c.HTTP_404_NOT_FOUND)
    try:
        version = m.Version.objects.get(pk=pk_version)
@ -135,7 +136,8 @@ def export_file(request: Request, pk: int):
        version = m.Version.objects.get(pk=pk)
    except m.Version.DoesNotExist:
        return Response(status=c.HTTP_404_NOT_FOUND)
-    data = s.RSFormTRSSerializer(m.RSForm(version.item)).from_versioned_data(version.data)
+    schema = m.RSForm.objects.get(pk=version.item.pk)
+    data = s.RSFormTRSSerializer(schema).from_versioned_data(version.data)
    file = utils.write_zipped_json(data, utils.EXTEOR_INNER_FILENAME)
    filename = utils.filename_for_schema(data['alias'])
    response = HttpResponse(file, content_type='application/zip')
--- a/rsconcept/backend/project/settings.py
+++ b/rsconcept/backend/project/settings.py
@ -79,6 +79,8 @@ INSTALLED_APPS = [
    'drf_spectacular',
    'drf_spectacular_sidecar',
 ]
+if DEBUG:
+    INSTALLED_APPS.append('django_extensions')


 REST_FRAMEWORK = {
@ -128,7 +130,6 @@ APPEND_SLASH = False

 # Static files (CSS, JavaScript, Images)
 # https://docs.djangoproject.com/en/4.1/howto/static-files/
-
 STATIC_ROOT = os.environ.get('STATIC_ROOT', os.path.join(BASE_DIR, 'static'))
 STATIC_URL = 'static/'
 MEDIA_ROOT = os.environ.get('MEDIA_ROOT', os.path.join(BASE_DIR, 'media'))
@ -156,7 +157,6 @@ WSGI_APPLICATION = 'project.wsgi.application'

 # Database
 # https://docs.djangoproject.com/en/4.1/ref/settings/#databases
-
 DATABASES = {
    'default': {
        'ENGINE': os.environ.get('DB_ENGINE', 'django.db.backends.sqlite3'),
@ -198,7 +198,6 @@ SPECTACULAR_SETTINGS = {

 # Password validation
 # https://docs.djangoproject.com/en/4.1/ref/settings/#auth-password-validators
-
 AUTH_PASSWORD_VALIDATORS: list[str] = [
    # NOTE: Password validators disabled
    # {
@ -231,6 +230,14 @@ USE_TZ = True
 DEFAULT_AUTO_FIELD = 'django.db.models.BigAutoField'


+# Graph model settings for visualization
+# https://django-extensions.readthedocs.io/en/latest/graph_models.html
+GRAPH_MODELS = {
+    'all_applications': True,
+    'group_models': True,
+}
+
+
 LOGGING = {
    'version': 1,
    'disable_existing_loggers': False,
--- a/rsconcept/backend/requirements-dev.txt
+++ b/rsconcept/backend/requirements-dev.txt
@ -14,6 +14,7 @@ psycopg2-binary
 gunicorn

 djangorestframework-stubs[compatible-mypy]
+django-extensions
 mypy
 pylint
 coverage
--- a/rsconcept/backend/shared/messages.py
+++ b/rsconcept/backend/shared/messages.py
@ -50,10 +50,6 @@ def typificationInvalidStr():
    return 'Invalid typification string'


-def libraryTypeUnexpected():
-    return 'Attempting to use invalid adaptor for non-RSForm item'
-
-
 def exteorFileVersionNotSupported():
    return 'Некорректный формат файла Экстеор. Сохраните файл в новой версии'

--- a/scripts/dev/GraphDB.ps1
+++ b/scripts/dev/GraphDB.ps1
@ -0,0 +1,16 @@
+# Generate DOT file for DB structure
+$backend = Resolve-Path -Path "${PSScriptRoot}\..\..\rsconcept\backend"
+
+function GenerateDOT() {
+  Set-Location $backend
+
+  $python = "${backend}\venv\Scripts\python.exe"
+  $djangoSrc = "${backend}\manage.py"
+
+  & $python $djangoSrc graph_models -o visualizeDB.dot
+
+  notepad.exe "${backend}\visualizeDB.dot"
+  Start-Process "https://dreampuf.github.io/GraphvizOnline"
+}
+
+GenerateDOT
--- a/scripts/dev/RunCoverage.ps1
+++ b/scripts/dev/RunCoverage.ps1
@ -2,7 +2,7 @@

 $backend = Resolve-Path -Path "$PSScriptRoot\..\..\rsconcept\backend"

-function RunLinters() {
+function RunCoverage() {
  BackendCoverage
 }

@ -20,4 +20,4 @@ function BackendCoverage() {
  Start-Process "$backend\htmlcov\index.html"
 }

-RunLinters
+RunCoverage