Rails - Nov 2005 - ANN: attr_immutable plugin

Hiho,

Thought this might of some use to someone out there.

   - John



------------------------------------------------------------------------ 
-------
DESCRIPTION:

   attr_immutable is simple plugin for Rails 0.14.3+ which will cause  
attributes
   flagged as immutable to be just that: immutable. The attributes  
flagged will
   be rendered frozen on read, and throw an  
ImmutableAttributeAssignmentError on
   assignment only *after* the record has been persisted (save/ 
create) or loaded
   (find).

   Comments and suggestions welcome.

------------------------------------------------------------------------ 
-------
INSTALLATION:

   Download and extract the following into your vendor/plugins  
directory.

     http://www.psynix.com/rails/attr_immutable/attr_immutable.tar.gz
     http://www.psynix.com/rails/attr_immutable/attr_immutable.tar.bz2

------------------------------------------------------------------------ 
-------
USAGE:

   class User < ActiveRecord
     attr_immutable :username      # Make username immutable after  
save/create
   end

   me = User.new
   me.username = ''testuser''          =>
''testuser''
   me.password = ''testpassword''      =>
''testpassword''
   me.save                           => true
   me.reload
   me.username.frozen?               => true
   me[:username].frozen?             => true
   me.attributes[''username''].frozen? => true
   me.username = ''anotherusername''   =>  
Plasma::ImmutableAttributeAssignmentError thrown
   me[:username] = ''anotherusername'' =>  
Plasma::ImmutableAttributeAssignmentError thrown

   This plugin was developed using Rails 0.14.3. It may work on previous
   versions. Use at your own risk.

--
John Meredith <jmeredith-0iPedL6B8ETQT0dZR+AlfA@public.gmane.org>

Don''t wanna step on your toes, but one could as well do

class User < ActiveRecord
	attr_protected :name
end


Then you as an admin would still have the possibilibty to change the  
username through proper controllers.


Your solution might have it''s place though - it''s certainly a
cleaner
solution if one never ever wants to change an attribute
(Just wrote this in case you didn''t know about attr_protected)


Cheers :)
Rob

Hi,

I''m fully aware of attr_protected ... it does however serve a  
different purpose ie. that of disabling mass assignment of specified  
attributes.

Thanks for the comments anyway :-)

   - John

On 28/11/2005, at 8:03 PM, Robert wrote:
> Don''t wanna step on your toes, but one could as well do
>
> class User < ActiveRecord
> 	attr_protected :name
> end
>
>
> Then you as an admin would still have the possibilibty to change  
> the username through proper controllers.
>
>
> Your solution might have it''s place though - it''s
certainly a
> cleaner solution if one never ever wants to change an attribute
> (Just wrote this in case you didn''t know about attr_protected)
>
>
> Cheers :)
> Rob
> _______________________________________________
> Rails mailing list
> Rails-1W37MKcQCpIf0INCOvqR/iCwEArCW2h5@public.gmane.org
> http://lists.rubyonrails.org/mailman/listinfo/rails
--
John Meredith <jmeredith-0iPedL6B8ETQT0dZR+AlfA@public.gmane.org>