# Should I use the validation framework (e.g. add\_to\_base) to pass back multiple data errors that are **URL:** \ **Category:** Rails\ **Created:** [January 20, 2009, 8:01am UTC](https://www.ruby-forum.com/t/should-i-use-the-validation-framework-e-g-add-to-base-to-pass-back-multiple-data-errors-that-are/158185 "2009-01-20T08:01:51Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![greg](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/g/71c47a/32.png) [@greg](https://www.ruby-forum.com/u/greg)\ **Post date:** [January 20, 2009, 8:01am UTC](https://www.ruby-forum.com/t/should-i-use-the-validation-framework-e-g-add-to-base-to-pass-back-multiple-data-errors-that-are/158185/1 "2009-01-20T08:01:51Z")
Hi, I have an “automation” model with some config data. When it runs it looks across other models and does some matching, however it also builds up a list of “duplicate data” type issues identified as part of the routine. In terms of how I capture this array of duplicate data issues and pass to a view for display what would Rails best practice suggest? For example: - use validation framework (e.g. add\_to\_base, and then the helper tags to display) even though the data is not associated with attributes in the model - extend an application\_error Exception to include an Array - just use an array to pass back to controller, which stores as an instance variable (@duplicates) and write custom code to display in view (i.e. won’t use error/validation tags) thanks – Greg [http://blog.gregnet.org/](http://blog.gregnet.org/) ---
**Author:** ![greg](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/g/71c47a/32.png) [@greg](https://www.ruby-forum.com/u/greg)\ **Post date:** [January 21, 2009, 2:10am UTC](https://www.ruby-forum.com/t/should-i-use-the-validation-framework-e-g-add-to-base-to-pass-back-multiple-data-errors-that-are/158185/2 "2009-01-21T02:10:38Z")
(bump) On Tue, Jan 20, 2009 at 5:00 PM, Greg H. \< removed\_email\_address@domain.invalid\> wrote: > - extend an application\_error Exception to include an Array – Greg [http://blog.gregnet.org/](http://blog.gregnet.org/) ---
**Author:** ![greg](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/g/71c47a/32.png) [@greg](https://www.ruby-forum.com/u/greg)\ **Post date:** [January 21, 2009, 2:33am UTC](https://www.ruby-forum.com/t/should-i-use-the-validation-framework-e-g-add-to-base-to-pass-back-multiple-data-errors-that-are/158185/3 "2009-01-21T02:33:27Z")
I don’t necessarily see what’s wrong with add\_to\_base. Seems somewhat logical to me but I don’t really know what you’re attempting to do 🙂 On Tue, Jan 20, 2009 at 7:09 PM, Greg H. ---
**Author:** ![greg](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/g/71c47a/32.png) [@greg](https://www.ruby-forum.com/u/greg)\ **Post date:** [January 21, 2009, 3:14am UTC](https://www.ruby-forum.com/t/should-i-use-the-validation-framework-e-g-add-to-base-to-pass-back-multiple-data-errors-that-are/158185/4 "2009-01-21T03:14:25Z")
I suppose I was questioning whether from a best practice position whether using Rails input validation framework (focused at the model level), for collecting non-severe error messages that cut across a whole controller action (e.g. multiple models may be involved), and for which they are not focused at input validation but rather error that occuring during processing, for the purpose of bundling these up and passing to a view and displaying? hope this makes sense in terms of clarifying my Rails best practice question. On Wed, Jan 21, 2009 at 11:32 AM, Brian H. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > > > a view for display what would Rails best practice suggest? For example: > > > > Greg > > [http://blog.gregnet.org/](http://blog.gregnet.org/) > > > > > > > > – Greg [http://blog.gregnet.org/](http://blog.gregnet.org/) ---
**Author:** ![greg](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/g/71c47a/32.png) [@greg](https://www.ruby-forum.com/u/greg)\ **Post date:** [January 21, 2009, 3:21am UTC](https://www.ruby-forum.com/t/should-i-use-the-validation-framework-e-g-add-to-base-to-pass-back-multiple-data-errors-that-are/158185/5 "2009-01-21T03:21:26Z")
You could always go with the “business logic always goes in models” rule, and the easy implementation is to do what you’re doing. Or you could build a brand new model with its own errors collection to encapsulate what it is you’re doing (presenter pattern?). I don’t think there’s really a _best practice_ for this… if you can justify the use to yourself based on what business rules you’re trying to implement, that may be your best practice. 🙂 My rule is always that NOTHING goes in the controller. A lot of times I’ve done an after\_validation callback and shoved stuff into the errors.base before. Done stuff with cc processing that way too. I’d love to hear from others on this too. On Tue, Jan 20, 2009 at 8:13 PM, Greg H.