# from sqlalchemy import *
# from sqlalchemy.orm import declarative_base,sessionmaker
#
# db_url = "mysql+pymysql://root:123456@127.0.0.1:3306/ai0824_001?charset=utf8mb4"
# # db_url = "mysql+pymysql://root:420821@localhost:3306/student_manage_system?charset=utf8mb4"

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

# 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_url = f"mysql+pymysql://{DB_USER}:{DB_PASSWORD}@{DB_HOST}:{DB_PORT}/{DB_NAME}?charset=utf8mb4"

engine = create_engine(db_url
                       , pool_size=50
                       , echo=True
                       )

Base = declarative_base()
Session = sessionmaker(bind=engine
                       ,autoflush=False
                       ,autocommit = False
                       )


def get_db():
    db = Session()
    try:
        yield db
    finally:
        db.close()