[storm] Bool database type

[James Henstridge]

On 05/08/07, Drew Smathers <drew.smathers at gmail.com> wrote:
> For Bool-type columns in a class it looks as if this directly maps to
> the equivalent boolean type (surprise) for the underlying database.
> My problem is with tables where the boolean type is not used and
> instead a single character (either '0'/'1', or 'Y'/'N') is used used
> for this.  It seems like the only way to achieve this now with storm
> is to write a custom property/variable like so:
>
> YesNoBoolVariable(Variable):
>   @staticmethod
>   def _parse_set(value, from_db):
>      ...
>      return ('N', 'Y')[bool(value)]
>
> YesNoBool(SimpleProperty):
>   variable_class = YesNoBoolVariable
>
> class Foo:
>   ...
>   ready = YesNoBool()
>
> Is the above the only way to do this?

You could probably use the Enum() column type.  Something like this:

    class Foo:
        ready = Enum(map={False: 'N', True: 'Y'})

This should handle getting values from the database as booleans as
well as setting them.  You could potentially use a helper function or
class if you have many columns that encode the data like this.

James.