initial-draft

services/db.py

@@ -0,0 +1,67 @@
+# from contextlib import contextmanager
+from typing import Any, Callable, Dict, TypeVar
+# from psycopg2.errors import UniqueViolation
+from sqlalchemy import Column, Integer, create_engine
+from sqlalchemy.ext.declarative import declarative_base
+from sqlalchemy.orm import Session
+from sqlalchemy.sql.schema import Table
+
+from settings import DB_URL
+
+engine = create_engine(DB_URL, echo=False, pool_size=10, max_overflow=20)
+
+T = TypeVar("T")
+
+REGISTRY: Dict[str, type] = {}
+
+
+# @contextmanager
+def local_session(src=""):
+    return Session(bind=engine, expire_on_commit=False)
+    
+    # try:
+    #     yield session
+    #     session.commit()
+    # except Exception as e:
+    #     if not (src == "create_shout" and isinstance(e, UniqueViolation)):
+    #         import traceback
+
+    #         session.rollback()
+    #         print(f"[services.db] {src}: {e}")
+
+    #         traceback.print_exc()
+
+    #         raise Exception("[services.db] exception")
+
+    # finally:
+    #     session.close()
+
+
+class Base(declarative_base()):
+    __table__: Table
+    __tablename__: str
+    __new__: Callable
+    __init__: Callable
+    __allow_unmapped__ = True
+    __abstract__ = True
+    __table_args__ = {"extend_existing": True}
+
+    id = Column(Integer, primary_key=True)
+
+    def __init_subclass__(cls, **kwargs):
+        REGISTRY[cls.__name__] = cls
+
+    def dict(self) -> Dict[str, Any]:
+        column_names = self.__table__.columns.keys()
+        if "_sa_instance_state" in column_names:
+            column_names.remove("_sa_instance_state")
+        try:
+            return {c: getattr(self, c) for c in column_names}
+        except Exception as e:
+            print(f"[services.db] Error dict: {e}")
+            return {}
+            
+    def update(self, values: Dict[str, Any]) -> None:
+            for key, value in values.items():
+                if hasattr(self, key):
+                    setattr(self, key, value)