from sqlalchemy import create_engine
from sqlalchemy.orm import sessionmaker,declarative_base


# 导入.env参数
# import os
# from dotenv import load_dotenv
# load_dotenv( )
# DB_USER = os.getenv("DB_USER", "root")
# DB_PASSWORD = os.getenv("DB_PASSWORD", "")
# DB_HOST = os.getenv("DB_HOST", "localhost")
# DB_PORT = os.getenv("DB_PORT", "3306")
# DB_NAME = os.getenv("DB_NAME", "student_manage_system")
#
# class_management_url = f"mysql+pymysql://{DB_USER}:{DB_PASSWORD}@{DB_HOST}:{DB_PORT}/{DB_NAME}?charset=utf8mb4"

class_management_url = "mysql+pymysql://root:123456@localhost:3306/student_manage_system?charset=utf8mb4"

engine = create_engine(class_management_url)
SessionLocal = sessionmaker(bind=engine,autocommit=False, autoflush=False)
Base = declarative_base()

# 获取数据库会话依赖
def get_db():
    db = SessionLocal()
    try :
        yield db
    finally:
        db.close()