Form Validation Default

I personally disagree with putting form validations in models. Form validations, as stated, are for forms, which is found in a view which is handled by controllers. Database validation in models is fine, but if you are using your models with different apps without a front end, things can get hairy quickly.

For your case though, you can always build different validation rule as a config file and load it that way. If what you're validation is something you can isolate to specific models, then I'd recommend using a library for validating each model object.

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