Form with multiple different ids, how to save - ruby-on-rails

Question

Don't know how to save a question form that will have 2 ids, event id and user id
User.rb
class User < ApplicationRecord
has_many :questions
has_many :answers
end
Event.rb
class Event < ApplicationRecord
has_many :questions, dependent: :destroy
accepts_nested_attributes_for :questions
end
Question.rb
class Question < ApplicationRecord
belongs_to :user
belongs_to :event
has_many :answers, dependent: :destroy
accepts_nested_attributes_for :answers
end
Answer.rb
class Answer < ApplicationRecord
belongs_to :user
belongs_to :question
scope :sorted, ->{ order(created_at: :asc) }
end
questions_controller.rb
def new
#question = current_user.questions.build
end
def create
#question = Question.new(question_params)
#question["user_id"] = current_user.id
respond_to do |format|
if #question.save
format.html { redirect_to #question, notice: 'Question was successfully created.' }
format.json { render :show, status: :created, location: #question }
else
format.html { render :new }
format.json { render json: #question.errors, status: :unprocessable_entity }
end
end
end
I have the standard form generated with the scaffold, but I cant piece together what I am missing from my limited knowledge and experience in rails on how to get every question that a user makes to be linked to a specific created event and show which user created that particular question (I would assume that each question entry will need a user_id and a event_id column)
<%= form_with(model: question, local: true) do |form| %>
<%= form.label :body %>
<%= form.rich_text_area :body %>
<%= form.submit 'Create Question' %>
<% end %>
Updated for Error:
When I try to create a question, each entry requires an event_id (an event has many questions) and a user_id (I want to show who created that question).
Are my models and controllers setup correctly? When I try to create a question for an event, the error "Event must exist" occurs
Updated with ERD pic ( Not sure if I should just have users or seperate into creators and users )
ERD after reading up on last update
I begun reading up more on data modelling and I came up with this ERD...I am still not very sure on achieving 3NF and setting up the relationships, and how to translate it to rails models but would be great to have comments on my ERD so I can learn.
Creator creates events that users can join. Creator creates questions that users can post answers. Each event has many questions and each question can have many answers.

Answer 1

If I understood you correctly, you need nested resources to achieve your goal. It means, that questions are nested inside events, like 'parent' event has 'children' questions. At first, change your routes:
resources :events do
resources :questions
end
Run rake routes in terminal and you will see new routes with :event_id parameter. Now on events#index you can add link_to 'Questions about this event', event_questions_path(event) near each event, the link will lead you to events/1/questions (1 is id of the event). In QuestionsController you have new parameter, event_id, which you can use to find needed Event or to assign as foreign key.
Change you form
<%= form_with(model: [#event, #question], local: true) do |form| %>
<%= form.label :body %>
<%= form.rich_text_area :body %>
<%= form.submit 'Create Question' %>
<% end %>
and controller a bit to work with nested routes
def new
#event = Event.find(params[:event_id])
#question = event.questions.build
end
def create
#event = Event.find(params[:event_id])
#question = event.questions.build(question_params)
#question.user_id = current_user.id
respond_to do |format|
if #question.save
format.html { redirect_to #question, notice: 'Question was successfully created.' }
format.json { render :show, status: :created, location: #question }
else
format.html { render :new }
format.json { render json: #question.errors, status: :unprocessable_entity }
end
end
end
Also, you should remove the line accepts_nested_attributes_for from Event and Question models, since you never use it