How to chain class methods together in Ruby on Rails?












0















I've got this in my Rails 5 model:



def self.payable

  open.where.not(:delivery_status => "draft")

end



def self.draft

  where(:delivery_status => "draft")

end



def self.open

  where(:payment_status => "open")

end


Is there a more elegant way to write the first method?



It would be great to chain the open and draft methods together like this:



def self.payable

  open.not(:draft)

end


Unfortunately, this doesn't work.






ruby-on-rails ruby







share|improve this question


















  • 1





    may be of help

    – potashin
    Nov 26 '18 at 13:36


















0















I've got this in my Rails 5 model:



def self.payable

  open.where.not(:delivery_status => "draft")

end



def self.draft

  where(:delivery_status => "draft")

end



def self.open

  where(:payment_status => "open")

end


Is there a more elegant way to write the first method?



It would be great to chain the open and draft methods together like this:



def self.payable

  open.not(:draft)

end


Unfortunately, this doesn't work.






ruby-on-rails ruby







share|improve this question


















  • 1





    may be of help

    – potashin
    Nov 26 '18 at 13:36
















0












0








0








I've got this in my Rails 5 model:



def self.payable

  open.where.not(:delivery_status => "draft")

end



def self.draft

  where(:delivery_status => "draft")

end



def self.open

  where(:payment_status => "open")

end


Is there a more elegant way to write the first method?



It would be great to chain the open and draft methods together like this:



def self.payable

  open.not(:draft)

end


Unfortunately, this doesn't work.






ruby-on-rails ruby







share|improve this question














I've got this in my Rails 5 model:



def self.payable

  open.where.not(:delivery_status => "draft")

end



def self.draft

  where(:delivery_status => "draft")

end



def self.open

  where(:payment_status => "open")

end


Is there a more elegant way to write the first method?



It would be great to chain the open and draft methods together like this:



def self.payable

  open.not(:draft)

end


Unfortunately, this doesn't work.






ruby-on-rails ruby




ruby-on-rails ruby






share|improve this question













share|improve this question











share|improve this question




share|improve this question










asked Nov 26 '18 at 13:17









Tintin81Tintin81

4,1731251115




4,1731251115








  • 1





    may be of help

    – potashin
    Nov 26 '18 at 13:36
















  • 1





    may be of help

    – potashin
    Nov 26 '18 at 13:36










1




1





may be of help

– potashin
Nov 26 '18 at 13:36







may be of help

– potashin
Nov 26 '18 at 13:36














2 Answers
2






active

oldest

votes


















1














To chain negated queries you can use this trick:



def self.payable

  open.where.not(id: draft)

end


Another alternative if you don't care if an ActiveRecord::Relation object is returned is using -, which returns an Array:



def self.payable

  open - draft

end


I would personally use scopes instead of class methods for queries: https://guides.rubyonrails.org/active_record_querying.html#scopes. So:



scope :draft, -> { where(:delivery_status => "draft") }

scope :open, -> { where(:payment_status => "open") }

scope :payable, -> { open.where.not(id: draft) }





share|improve this answer





















  • 1





    "This is exactly the same as defining a class method, and which you use is a matter of personal preference". From the documentation you linked

    – Ursus
    Nov 26 '18 at 14:17



















1














Maybe you can use scopes? 



scope :payable, -> { open.where.not(:delivery_status => "draft") }


You can use this like that



YouModel.payable





share|improve this answer























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    2 Answers
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    active

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    active

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    1














    To chain negated queries you can use this trick:



    def self.payable
    
  open.where.not(id: draft)
    
end


    Another alternative if you don't care if an ActiveRecord::Relation object is returned is using -, which returns an Array:



    def self.payable
    
  open - draft
    
end


    I would personally use scopes instead of class methods for queries: https://guides.rubyonrails.org/active_record_querying.html#scopes. So:



    scope :draft, -> { where(:delivery_status => "draft") }
    
scope :open, -> { where(:payment_status => "open") }
    
scope :payable, -> { open.where.not(id: draft) }





    share|improve this answer





















    • 1





      "This is exactly the same as defining a class method, and which you use is a matter of personal preference". From the documentation you linked

      – Ursus
      Nov 26 '18 at 14:17
















    1














    To chain negated queries you can use this trick:



    def self.payable
    
  open.where.not(id: draft)
    
end


    Another alternative if you don't care if an ActiveRecord::Relation object is returned is using -, which returns an Array:



    def self.payable
    
  open - draft
    
end


    I would personally use scopes instead of class methods for queries: https://guides.rubyonrails.org/active_record_querying.html#scopes. So:



    scope :draft, -> { where(:delivery_status => "draft") }
    
scope :open, -> { where(:payment_status => "open") }
    
scope :payable, -> { open.where.not(id: draft) }





    share|improve this answer





















    • 1





      "This is exactly the same as defining a class method, and which you use is a matter of personal preference". From the documentation you linked

      – Ursus
      Nov 26 '18 at 14:17














    1












    1








    1







    To chain negated queries you can use this trick:



    def self.payable
    
  open.where.not(id: draft)
    
end


    Another alternative if you don't care if an ActiveRecord::Relation object is returned is using -, which returns an Array:



    def self.payable
    
  open - draft
    
end


    I would personally use scopes instead of class methods for queries: https://guides.rubyonrails.org/active_record_querying.html#scopes. So:



    scope :draft, -> { where(:delivery_status => "draft") }
    
scope :open, -> { where(:payment_status => "open") }
    
scope :payable, -> { open.where.not(id: draft) }





    share|improve this answer















    To chain negated queries you can use this trick:



    def self.payable
    
  open.where.not(id: draft)
    
end


    Another alternative if you don't care if an ActiveRecord::Relation object is returned is using -, which returns an Array:



    def self.payable
    
  open - draft
    
end


    I would personally use scopes instead of class methods for queries: https://guides.rubyonrails.org/active_record_querying.html#scopes. So:



    scope :draft, -> { where(:delivery_status => "draft") }
    
scope :open, -> { where(:payment_status => "open") }
    
scope :payable, -> { open.where.not(id: draft) }






    share|improve this answer














    share|improve this answer



    share|improve this answer








    edited Nov 27 '18 at 5:20









    sawa

    131k29205302




    131k29205302










    answered Nov 26 '18 at 14:02









    Ana María Martínez GómezAna María Martínez Gómez

    1,400721




    1,400721








    • 1





      "This is exactly the same as defining a class method, and which you use is a matter of personal preference". From the documentation you linked

      – Ursus
      Nov 26 '18 at 14:17














    • 1





      "This is exactly the same as defining a class method, and which you use is a matter of personal preference". From the documentation you linked

      – Ursus
      Nov 26 '18 at 14:17








    1




    1





    "This is exactly the same as defining a class method, and which you use is a matter of personal preference". From the documentation you linked

    – Ursus
    Nov 26 '18 at 14:17





    "This is exactly the same as defining a class method, and which you use is a matter of personal preference". From the documentation you linked

    – Ursus
    Nov 26 '18 at 14:17













    1














    Maybe you can use scopes? 



    scope :payable, -> { open.where.not(:delivery_status => "draft") }


    You can use this like that



    YouModel.payable





    share|improve this answer




























      1














      Maybe you can use scopes? 



      scope :payable, -> { open.where.not(:delivery_status => "draft") }


      You can use this like that



      YouModel.payable





      share|improve this answer


























        1












        1








        1







        Maybe you can use scopes? 



        scope :payable, -> { open.where.not(:delivery_status => "draft") }


        You can use this like that



        YouModel.payable





        share|improve this answer













        Maybe you can use scopes? 



        scope :payable, -> { open.where.not(:delivery_status => "draft") }


        You can use this like that



        YouModel.payable






        share|improve this answer












        share|improve this answer



        share|improve this answer










        answered Nov 26 '18 at 13:34









        KosBloKosBlo

        192




        192






























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