from sqlalchemy import *
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")

db_tea = 'mysql+pymysql://root:123456@127.0.0.1:3306/student_manage_system?charset=utf8mb4'
engine1 = create_engine(db_tea)

Base = declarative_base()
Session = sessionmaker(bind=engine1
                       ,autoflush = False
                       ,autocommit = False)
def get_db():
    db = Session()
    try:
        yield db
    finally:
        db.close()
Base.metadata.create_all(engine1)