Hi All,
I am trying to write a model that will encrypt all data at the
database level, but can be accessed easily through normal attributes.
I stumbled across the hybrid_property feature and it works fine, as
long as I don't try and filter() or filter_by() my hybrid_property.
The thing is it'd be quite nice to filter by the hybrid_properties as
these are the friendly names for encrypted data in the database.
Here's a cut-down version of my class:
----------------------------------------------------------------------
class User(object):
username_enc = Column(String(128))
@hybrid_attribute
def username(self):
return decrypt_string(self.username_enc)
@username.setter
def username(self, value):
return self.username_enc = encrypt_string(value)
@username.expression
def username(cls):
return func(decrypt_string(cls.username_enc))
user1 = User()
user1.username = 'test1'
print user1.username # works
print user1.username_enc # works
----------------------------------------------------------------------
This works fine on the object itself for getting and setting values,
but if I try to do the following it fails in my "encrypt_string"
function complaining that the type should be a string and not a
InstrumentedAttribute.
User.query.filter(User.username == 'test1').first()
The error message regarding "InstrumentedAttribute" is because
base64.b64decode() expects a buffer, rather than an
InstrumentedAttribute to decode, but what I don't understand is how to
get it to filter based on the encrypted version of the username when
the front-end code tries to filter on 'username'
SQLAlchemy: 0.7.6
Python: 2.7
Any help would be appreciated.
Cheers,
David.
--
You received this message because you are subscribed to the Google Groups
"sqlalchemy" group.
To post to this group, send email to [email protected].
To unsubscribe from this group, send email to
[email protected].
For more options, visit this group at
http://groups.google.com/group/sqlalchemy?hl=en.
