ActionController::UrlGenerationError - missing required keys - ruby-on-rails

Question

I am new to rails and am trying to build my first MVC app. I am trying to create a link file path and get this error message -
ActionController::UrlGenerationError in Pages#my_profile
No route matches {:action=>"show", :car_id=>10, :controller=>"bookings"}, missing required keys: [:id]
This is the code I am using in the view
<% current_user.bookings.each do |booking| %>
<%= link_to booking.car.make, car_booking_path(booking[:id])%></h2>
<% end %>
When I type booking into the rails console I have access to the following hash
#<Booking id: 10, start_date: "2020-08-18", end_date: "2020-08-19", status: nil, user_id: 5, car_id: 5, created_at: "2020-08-18 17:34:41", updated_at: "2020-08-18 17:34:41">
so am unsure as to why, when booking[:id] is passed it is not picked.
my route is
car_booking GET /cars/:car_id/bookings/:id(.:format) bookings#show
Does anyone have any idea on what I am missing?
any help would be massively appreciated.

Answer 1

Try:
<% current_user.bookings.each do |booking| %>
<%= link_to booking.car.make, [booking.car, booking] %></h2>
<% end %>
See, you have a nested route:
car_booking GET /cars/:car_id/bookings/:id(.:format) bookings#show
Which expects both car_id and id. You're only passing in one value, booking[:id], which is in the first position, so it is interpreted as car_id (although it's actually booking.id). There is no second value in your arguments, so you get the missing required keys: [:id] message.
Note that if you used shallow nesting, something like this:
Rails.application.routes.draw do
...
resources :cars do
resources :bookings, shallow: true
end
...
end
then you would just do:
<% current_user.bookings.each do |booking| %>
<%= link_to booking.car.make, booking_path(booking)%></h2>
<% end %>
Also note that you can typically do booking_path(booking) instead of booking_path(booking.id). In fact, as stated in the docs, you can use the pithier:
<% current_user.bookings.each do |booking| %>
<%= link_to booking.car.make, booking %></h2>
<% end %>
If you don't want to use shallow nesting, you can do:
<% current_user.bookings.each do |booking| %>
<%= link_to booking.car.make, [booking.car, booking] %></h2>
<% end %>
...and, as discussed in the docs Rails will infer the car_booking_path helper.
In your question, you say you have access to the following hash:
#<Booking id: 10, start_date: "2020-08-18", end_date: "2020-08-19", status: nil, user_id: 5, car_id: 5, created_at: "2020-08-18 17:34:41", updated_at: "2020-08-18 17:34:41">
FYI, that's not a hash. That's an instance of the Booking class which inherits from ActiveRecord::Base. To get the id from that instance, do booking.id, not booking[:id].

Answer 2

As per the output from the routes, you need to pass two arguments id and car_id.
Try the below:
<%= link_to booking.car.make, car_booking_path(car_id: booking.car_id, id: booking.id)%></h2>