ruby on rails - Get validation errors only on #valid? -

i have model field validating content in field. using activerecord validations check presence of content. however, want able save, update, etc, without checking validity. want validity @ 1 specific time, , retrieve errors it.

validates :my_content_in_field, presence: true, if: :should_validate attr_accessor :should_validate 

i want pass

valid? 

and fail

valid?(should_validate: true) 

and after failed validation want updates , saves work per usual. possible? want leverage activerecords error messages, not validate otherwise.

at end of day on friday, may missing obvious.

i'm not sure can call valid?(should_validate: true). valid? method may called 1 parameter called context (see docs). should read a great post on validation contexts.

this should work:

class mymodel < activerecord::base   validates :something, on: :should_validate   ... end  m = mymodel.new m.valid?                    # no validation happens m.valid?(:should_validate)  # validates