delete session messages with cascade

alembic/versions/9f03cceaa492_add_cascade_delete_to_chat_messages.py

@@ -0,0 +1,48 @@
+"""add cascade delete to chat messages
+
+Revision ID: 9f03cceaa492
+Revises: 34aaf324bd00
+Create Date: 2026-01-06 22:57:13.810344
+
+"""
+from typing import Sequence, Union
+
+from alembic import op
+import sqlalchemy as sa
+import sqlmodel
+
+# revision identifiers, used by Alembic.
+revision: str = '9f03cceaa492'
+down_revision: Union[str, Sequence[str], None] = '34aaf324bd00'
+branch_labels: Union[str, Sequence[str], None] = None
+depends_on: Union[str, Sequence[str], None] = None
+
+
+def upgrade() -> None:
+    # PostgreSQL'de constraint'i direkt değiştirmek için
+    op.execute("""
+        ALTER TABLE chat_messages 
+        DROP CONSTRAINT IF EXISTS chat_messages_session_id_fkey;
+    """)
+    
+    op.execute("""
+        ALTER TABLE chat_messages 
+        ADD CONSTRAINT chat_messages_session_id_fkey 
+        FOREIGN KEY (session_id) 
+        REFERENCES chat_sessions(id) 
+        ON DELETE CASCADE;
+    """)
+
+
+def downgrade() -> None:
+    op.execute("""
+        ALTER TABLE chat_messages 
+        DROP CONSTRAINT IF EXISTS chat_messages_session_id_fkey;
+    """)
+    
+    op.execute("""
+        ALTER TABLE chat_messages 
+        ADD CONSTRAINT chat_messages_session_id_fkey 
+        FOREIGN KEY (session_id) 
+        REFERENCES chat_sessions(id);
+    """)

src/api/selectors/chat/delete_chat_session.py

@@ -9,9 +9,14 @@ async def delete_chat_session(
     user_id: int,
     db: AsyncSession
 ) -> None:
-    statement = delete(ChatSession).where(
+    message_statement = delete(ChatMessage).where(
+        ChatMessage.session_id == session_id
+    )
+    await db.execute(message_statement)
+
+    session_statement = delete(ChatSession).where(
         ChatSession.id == session_id,
         ChatSession.user_id == user_id 
     )
-    await db.execute(statement)
+    await db.execute(session_statement)
     await db.commit()