Question

I made a relationship with the three models using has_many :through:

class Curriculum class < ActiveRecord::Base

    has_many :interests
    has_many :vacancies,: through => :interests
end

class Vacancy class < ActiveRecord::Base

   has_many :interests
   has_many :resumes,: through => :interests
end

class Interest < ActiveRecord:: Base

    belongs_to :vacancy
    belongs_to :curriculum
end

And to create curriculum and vacancy, I create them by administrative, i need to know how can i create the interest to the id of the vacancy, and how it will be logged on the system I have to get the id of it and make the relationship in creating a new bank interest. I wonder how I can program it to do so, and I wonder how the controller will get the create action, and what better way to do this.

Answer 1

First, try to read the whole “Guide to Rails on Associations”, especially the part about has_many :through. Then check your schema if your db is migrated and contains for the table interests the necessary foreign keys to curriculums and vacancies called curriculum_id and vacancy_id.

If that is all in place, the following code will create the relationship between two objects:

@curr = Curriculum.find(1)
@vac = Vacancy.find(1)
@curr.interests << @vac
@curr.save

The last two lines creates an interest between @curr and @vac and store that on the database. So you should not use IDs and handle them directly, but work with objects instead.

The second part now is to provide a UI to allow the definition (and removal) of interests between curricula and vacancies. The base flow here is:

• You have one curriculum in focus.
• You have a link to add / remove curricula.
• The view that opens shows a list of possible vacancies, where every vacancy has a checkbox.
• By selecting (or deselecting) the check boxes, the IDs of the vacancies will be held in the params of the request sent to the controller.

See the (older) podcast Railscast #52 how to do that in a similar context. Or see the example for has_many :through with checkboxes.

An alternative way would be to use JQuery autocomplete, and add so interests one-by-one. See the nice podcast Railscast #258 which uses JQuery Tokeninput for that.