How do I pass an object in the rails URL helper - ruby-on-rails

Question

I'm having an issue understanding how to setup the routes in rails to pass an object into the URL helper.
I added a new method add_item
def add_item
#item = Item.create(item_params)
puts #hospital.inspect
puts #item.inspect
#hospital.items << #item
respond_to do |format|
if #hospital.save
format.html { redirect_to hospital_url(#hospital), notice: "Item was added to hospital" }
format.json { render :show, status: :ok, location: #hospital }
else
format.html { render :edit, status: :unprocessable_entity }
format.json { render json: #hospital.errors, status: :unprocessable_entity }
end
end
end
I added the corresponding route
resources :hospitals do
member do
post :add_item
end
end
but when I run my test that uses
post add_item_hospital_url(#hospital), params: { item: { item_code: item.item_code, description: item.description, gross_charge: item.gross_charge } }
the #hospital in the test is not nil but on the controller, it is. What am I doing wrong?
My routes seem to be okay.
add_item_hospital POST /hospitals/:id/add_item(.:format)

Answer 1

The instance variable #hospital is nil in the controller because it has not been set. Maybe you could add a before_action to set the value of the instance variable or just add it to the add_item method.
When passing models into the URL helper the id of that object can be found within the params hash
class HospitalsController < ApplicationController
before_action :set_hospital, only: :add_item
def add_item
# ... your code here
end
private
def set_hospital
#hospital = Hospital.find(params[:id])
rescue ActiveRecord::RecordNotFound
# handle exception
end
end