Add new DAL and update code to create missing database

data/database.py

@@ -3,10 +3,13 @@
 
     The base definitions for database access and definition
 """
-from datetime import datetime
+from datetime import date, datetime
+from typing import Any, Sequence, TypeVar
 
-from sqlalchemy import create_engine, Date, Integer, MetaData, String
+from sqlalchemy import create_engine, Date, engine, func, Integer, MetaData, Row, text
-from sqlalchemy.orm import DeclarativeBase, Mapped, mapped_column, sessionmaker
+from sqlalchemy.exc import IntegrityError, PendingRollbackError
+from sqlalchemy.orm import DeclarativeBase, Mapped, mapped_column, sessionmaker, Session
+from sqlalchemy_utils import create_database, database_exists
 
 from util.environment import load_environment_variables
 
@@ -32,20 +35,7 @@ class Base(DeclarativeBase):
     metadata = MetaData(naming_convention=DATABASE_NAMING_CONVENTION)
 
 
-class DataAccessLayer:
+Table = TypeVar("Table", bound=Base)
-
-    def __init__(self):
-        self.engine = None
-        self.conn_string = project_variables["LP_DATABASE_URL"]
-
-
-    def connect(self):
-        self.engine = create_engine(self.conn_string)
-        Base.metadata.create_all(self.engine)
-        self.Session = sessionmaker(bind=self.engine)
-
-
-dal = DataAccessLayer()
 
 
 class PowerballDraw(Base):
@@ -102,3 +92,64 @@ class MegaMillionsDraw(Base):
             self.main_ball2 == other.main_ball2 and self.main_ball3 == other.main_ball3 and \
             self.main_ball4 == other.main_ball4 and self.main_ball5 == other.main_ball5 and \
             self.mega_ball == other.mega_ball and self.megaplier == other.megaplier
+
+
+class DataAccessLayer:
+
+    def __init__(self):
+        self.engine = None
+        self.conn_string = project_variables["LP_DATABASE_URL"]
+
+
+    def connect(self):
+        self.engine = create_engine(self.conn_string)
+        if not database_exists(self.engine.url):
+            create_database(self.engine.url)
+            Base.metadata.create_all(self.engine)
+        self.Session = sessionmaker(bind=self.engine)
+
+
+class DataAccessLayer2:
+
+    def __init__(self):
+        self.engine = create_engine(project_variables["LP_DATABASE_URL"], echo=False)
+        if not database_exists(self.engine.url):
+            create_database(self.engine.url)
+            Base.metadata.create_all(self.engine)
+        self.session_local: sessionmaker[Session] = sessionmaker(bind=self.engine)
+        self.session_factory = self.session_local
+
+    def execute_query(self, query) -> Sequence[Row[Any]]:
+        with self.session_factory() as session:
+            try:
+                result = session.execute(text(query))
+                return result.fetchall()
+            finally:
+                session.close()
+
+    def add(self, record: Table) -> None:
+        with self.session_factory() as session:
+            try:
+                session.add(record)
+                session.commit()
+            except IntegrityError:
+                session.rollback()
+            except PendingRollbackError:
+                session.rollback()
+            finally:
+                session.close()
+
+    def count(self, table_name: str, from_date: date | None = None) -> int:
+        with self.session_factory() as session:
+            if from_date:
+                return session.query(table_name).where(table_name.draw_date >= from_date).count()
+            else:
+                return session.query(table_name).count()
+
+    def most_recent(self, table_name: Table) -> Row[Table] | None:
+        with self.session_factory() as session:
+            return session.query(func.max(table_name.draw_date)).first()
+
+
+dal = DataAccessLayer()
+dal2 = DataAccessLayer2()