sqlalchemy - 在运行时为 SQLAlchemy 的 `EncryptedType` 指定一个键

Question

SQLAlchemy-Utils documentation for the EncryptedType column type有一个看起来像这样的例子:

secret_key = 'secretkey1234'
# setup
engine = create_engine('sqlite:///:memory:')
connection = engine.connect()
Base = declarative_base()


class User(Base):
    __tablename__ = "user"
    id = sa.Column(sa.Integer, primary_key=True)
    username = sa.Column(EncryptedType(sa.Unicode,
                                       secret_key,
                                       AesEngine,
                                       'pkcs5'))

但是如果我在定义 User 类之前不知道 key 是什么怎么办？比如我想提示用户输入秘钥怎么办？

Answer 1

这是 docs 中的最后一个示例您链接到:

The key parameter accepts a callable to allow for the key to change per-row instead of being fixed for the whole table.

def get_key():
    return 'dynamic-key'

class User(Base):
    __tablename__ = 'user'
    id = sa.Column(sa.Integer, primary_key=True)
    username = sa.Column(EncryptedType(
        sa.Unicode, get_key))