all tests passes - creating dummy models if fk not nullable

orm/fields.py

@@ -1,14 +1,17 @@
 import datetime
 import decimal
-from typing import Optional, List
+from typing import Optional, List, Type, TYPE_CHECKING
 
-import orm
 import sqlalchemy
 from pydantic import Json
 from pydantic.fields import ModelField
 
+import orm
 from orm.exceptions import ModelDefinitionError, RelationshipInstanceError
 
+if TYPE_CHECKING:  # pragma no cover
+    from orm.models import Model
+
 
 class BaseField:
     __type__ = None
@@ -173,8 +176,16 @@ class Decimal(BaseField):
         return sqlalchemy.DECIMAL(self.length, self.precision)
 
 
+def create_dummy_instance(fk: Type['Model'], pk: int = None):
+    init_dict = {fk.__pkname__: pk or -1}
+    init_dict = {**init_dict, **{k: create_dummy_instance(v.to)
+                                 for k, v in fk.__model_fields__.items()
+                                 if isinstance(v, ForeignKey) and not v.nullable and not v.virtual}}
+    return fk(**init_dict)
+
+
 class ForeignKey(BaseField):
-    def __init__(self, to, related_name: str = None, nullable: bool = False, virtual: bool = False):
+    def __init__(self, to, related_name: str = None, nullable: bool = True, virtual: bool = False):
         super().__init__(nullable=nullable)
         self.virtual = virtual
         self.related_name = related_name
@@ -206,14 +217,15 @@ class ForeignKey(BaseField):
         elif isinstance(value, dict):
             model = self.to(**value)
         else:
-            model = self.to(**{self.to.__pkname__: value})
+            model = create_dummy_instance(fk=self.to, pk=value)
 
         child_model_name = self.related_name or child.__class__.__name__.lower() + 's'
         model._orm_relationship_manager.add_relation(model.__class__.__name__.lower(),
                                                      child.__class__.__name__.lower(),
                                                      model, child, virtual=self.virtual)
 
-        if child_model_name not in model.__fields__:
+        if child_model_name not in model.__fields__ \
+                and child.__class__.__name__.lower() not in model.__fields__:
             model.__fields__[child_model_name] = ModelField(name=child_model_name,
                                                             type_=Optional[child.__pydantic_model__],
                                                             model_config=child.__pydantic_model__.__config__,

orm/queryset.py

@@ -57,11 +57,17 @@ class QuerySet:
                     f'{previous_alias + "_" if previous_alias else ""}{from_table}.{from_key}')
 
     def build_select_expression(self):
-        tables = [self.table]
+        # tables = [self.table]
         columns = list(self.table.columns)
         order_bys = [text(f'{self.table.name}.{self.model_cls.__pkname__}')]
         select_from = self.table
 
+        for key in self.model_cls.__model_fields__:
+            if not self.model_cls.__model_fields__[key].nullable \
+                    and isinstance(self.model_cls.__model_fields__[key], orm.fields.ForeignKey) \
+                    and key not in self._select_related:
+                self._select_related.append(key)
+
         for item in self._select_related:
             previous_alias = ''
             from_table = self.table.name
@@ -86,7 +92,7 @@ class QuerySet:
                 on_clause = self.on_clause(from_table, to_table, previous_alias, alias, to_key, from_key)
                 target_table = self.prefixed_table_name(alias, to_table)
                 select_from = sqlalchemy.sql.outerjoin(select_from, target_table, on_clause)
-                tables.append(model_cls.__table__)
+                # tables.append(model_cls.__table__)
                 order_bys.append(text(f'{alias}_{to_table}.{model_cls.__pkname__}'))
                 columns.extend(self.prefixed_columns(alias, model_cls.__table__))
 

tests/test_same_table_joins.py

@@ -14,7 +14,7 @@ class Department(orm.Model):
     __metadata__ = metadata
     __database__ = database
 
-    id = orm.Integer(primary_key=True)
+    id = orm.Integer(primary_key=True, autoincrement=False)
     name = orm.String(length=100)
 
 
@@ -25,7 +25,7 @@ class SchoolClass(orm.Model):
 
     id = orm.Integer(primary_key=True)
     name = orm.String(length=100)
-    department = orm.ForeignKey(Department)
+    department = orm.ForeignKey(Department, nullable=False)
 
 
 class Category(orm.Model):
@@ -70,7 +70,7 @@ def create_test_database():
 @pytest.mark.asyncio
 async def test_model_multiple_instances_of_same_table_in_schema():
     async with database:
-        department = await Department.objects.create(name='Math Department')
+        department = await Department.objects.create(id=1, name='Math Department')
         class1 = await SchoolClass.objects.create(name="Math", department=department)
         category = await Category.objects.create(name="Foreign")
         category2 = await Category.objects.create(name="Domestic")
@@ -91,7 +91,7 @@ async def test_model_multiple_instances_of_same_table_in_schema():
 @pytest.mark.asyncio
 async def test_right_tables_join():
     async with database:
-        department = await Department.objects.create(name='Math Department')
+        department = await Department.objects.create(id=1, name='Math Department')
         class1 = await SchoolClass.objects.create(name="Math", department=department)
         category = await Category.objects.create(name="Foreign")
         category2 = await Category.objects.create(name="Domestic")
@@ -111,7 +111,7 @@ async def test_right_tables_join():
 @pytest.mark.asyncio
 async def test_multiple_reverse_related_objects():
     async with database:
-        department = await Department.objects.create(name='Math Department')
+        department = await Department.objects.create(id=1, name='Math Department')
         class1 = await SchoolClass.objects.create(name="Math", department=department)
         category = await Category.objects.create(name="Foreign")
         category2 = await Category.objects.create(name="Domestic")