Create interdependent association model in rails - Best pratice -

what best practice creating associated models e.g. not want save if 1 of validation fails(say c). also, show error each model if any.

class  has_many :b  has_many :c end  class b end  class c end  class acontroller   def create     afields = params[:a_params]     bfields = params[:b_params]     cfields = params[:c_params]      = a.new(a_params)      if a.save       b.create(bfields)       c.create(cfields)       redirect_to a_index     else       redirect_to a_new_path     end       end end 

basically, want create lot of interdependent models , want save of them or none if single validation fails. can way or other know best way it.

you can use activerecord validation's validates_associated method serve purpose:

class < activerecord::base  has_many :b  has_many :c   validates_associated :b, :c end 

edit:

you alternatively use, validates_associated in b , c models this:

class b < activerecord::base  belongs_to :a   validates_associated :a end  class c < activerecord::base  belongs_to :a   validates_associated :a end 

that way, ensure associated a present before creating b's record or c's record.

but careful, can't use validates_associated in both associations (has_many , belongs_to) cause infinite recursion.