hoàn thành phần Authentication

backend/app/database.py

@@ -0,0 +1,23 @@
+from sqlalchemy import create_engine
+from sqlalchemy.orm import DeclarativeBase, sessionmaker
+import os
+
+DATABASE_URL = os.getenv(
+    "DATABASE_URL",
+    "postgresql+psycopg2://lms_user:lms_password@db:5432/lms_db",
+)
+
+engine = create_engine(DATABASE_URL, pool_pre_ping=True)
+SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)
+
+
+class Base(DeclarativeBase):
+    pass
+
+
+def get_db():
+    db = SessionLocal()
+    try:
+        yield db
+    finally:
+        db.close()