sqlalchemy根據表名動態創建model類

作用如題，直接上代碼吧，另外還支持 copy一張表的表結構，新建表並獲得model對象

# coding: utf-8
import traceback

from sqlalchemy import (BigInteger, Column, DateTime, Integer, MetaData,
                        String, Table, create_engine, text)
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy.orm import mapper
from sqlalchemy.schema import CreateTable


# 本地數據庫
engineLocal = create_engine('mysql+pymysql://root:root@127.0.0.1:3306/lingyun?charset=utf8')


Base = declarative_base()
metadata = MetaData()

def dictToObj(results, to_class):
    """將字典list或者字典轉化為指定類的對象list或指定類的對象
    python 支持動態給對象添加屬性，所以字典中存在而該類不存在的會直接添加到對應對象
    """
    if isinstance(results, list):
        objL = []
        for result in results:
            obj = to_class()
            for r in result.keys():
                obj.__setattr__(r, result[r])
            objL.append(obj)
        return objL
    else:
        try:
            obj = to_class()
            for r in results.keys():
                obj.__setattr__(r, results[r])
            return obj
        except Exception as e:
            print(e)
            traceback.print_exc()
            return None
    # else:
    #     print("傳入對象非字典或者list")
    #     return None

def getModel(name, engine):
    """根據name創建並return一個新的model類
    name:數據庫表名
    engine:create_engine返回的對象，指定要操作的數據庫連接，from sqlalchemy import create_engine
    """
    Base.metadata.reflect(engine)
    table = Base.metadata.tables[name]
    t = type(name,(object,),dict())
    mapper(t, table)
    Base.metadata.clear()
    return t

def createTableFromTable(name, tableNam, engine):
    """copy一個已有表的結構，並創建新的表
    """
    metadata = MetaData(engine)
    Base.metadata.reflect(engine)
    # 獲取原表對象
    table = Base.metadata.tables[tableNam]
    # 獲取原表建表語句
    c = str(CreateTable(table))
    # 替換表名
    c = c.replace("CREATE TABLE " + tableNam, "CREATE TABLE if not exists " + name)
    db_conn = engine.connect()
    db_conn.execute(c)
    db_conn.close()
    Base.metadata.clear()

def getNewModel(name, tableNam, engine):
    """copy一個表的表結構並創建新的名為name的表並返回model類
    name:數據庫表名
    tableNam:copy的表表名
    engine:create_engine返回的對象，指定要操作的數據庫連接，from sqlalchemy import create_engine
    """
    createTableFromTable(name, tableNam, engine)
    return getModel(name, engine)

　https://blog.csdn.net/j_object/article/details/80118657