Rails: Item not saving to database (routing with nested resources) - ruby-on-rails

Question

I'm running into a problem when trying to create a new object using nested resources in Rails. My routing is set up as:
resources :coins do
resources :questions
resources :events
end
When I attempt to create a new event, it does not save. Adding ! to event.save gave me an error that says "Validation failed: Coin must exist".
I don't have a validation set up for the coin (in the Event model at least, if that is what its referring to). Checking the log file shows the following, which as far as I can tell shows that the correct coin is selected:
Started GET "/coins/1/events/new" for 127.0.0.1 at 2018-01-24 18:52:19 -0500
Processing by EventsController#new as HTML
Parameters: {"coin_id"=>"1"}
[1m[36mCoin Load (0.1ms)[0m [1m[34mSELECT "coins".* FROM "coins" WHERE "coins"."id" = ? LIMIT ?[0m [["id", 1], ["LIMIT", 1]]
[1m[36mUser Load (0.2ms)[0m [1m[34mSELECT "users".* FROM "users" WHERE "users"."id" = ? ORDER BY "users"."id" ASC LIMIT ?[0m [["id", 1], ["LIMIT", 1]]
Rendering events/new.html.erb within layouts/application
Rendered events/new.html.erb within layouts/application (3.9ms)
Rendered layouts/_rails_defaults.html.erb (34.8ms)
Rendered layouts/_shim.html.erb (0.6ms)
Rendered layouts/_header.html.erb (6.2ms)
Completed 200 OK in 67ms (Views: 62.3ms | ActiveRecord: 0.3ms)
Started POST "/coins/1/events" for 127.0.0.1 at 2018-01-24 18:54:46 -0500
Processing by EventsController#create as HTML
Parameters: {"utf8"=>"✓", "authenticity_token"=>"dAXQ3uwxR2IN2rbAYD//gulHebIOdZWFPYCKnxcUKTuV4QnUp+SZYHMpZUsGOgEXQjOAnhFUO9MpJkIIAKcQlQ==", "event"=>{"content"=>"LKNA", "link"=>"asd"}, "commit"=>"Submit", "coin_id"=>"1"}
[1m[36mCoin Load (0.2ms)[0m [1m[34mSELECT "coins".* FROM "coins" WHERE "coins"."id" = ? LIMIT ?[0m [["id", 1], ["LIMIT", 1]]
[1m[36mUser Load (0.2ms)[0m [1m[34mSELECT "users".* FROM "users" WHERE "users"."id" = ? ORDER BY "users"."id" ASC LIMIT ?[0m [["id", 1], ["LIMIT", 1]]
[1m[35m (0.1ms)[0m [1m[36mbegin transaction[0m
[1m[35m (0.0ms)[0m [1m[31mrollback transaction[0m
Completed 401 Unauthorized in 66ms (ActiveRecord: 3.0ms)
ActiveRecord::RecordInvalid (Validation failed: Coin must exist):
app/controllers/events_controller.rb:23:in `create'
I have it set up the same way for my Questions model, as they are almost identical aside from names, and that one works with no issues. I'm at a loss as to what I'm doing incorrectly here.
controller:
class EventsController < ApplicationController
before_action :find_event, only: [:show, :edit, :update, :destroy ]
before_action :find_coin
def index
#events = Event.where(coin_id: #coin.id).order("created_at DESC")
end
def show
end
def new
#event = current_user.events.build
end
def create
#event = current_user.events.build(event_params)
if #event.save!
flash[:success] = "Event Saved"
redirect_to coin_event_path(#coin.id, #event.id)
else
flash[:notice] = "Event *NOT* Saved!!!"
render 'new'
#event.errors.full_messages
end
end
.
.
.
private
def find_event
#event = Event.find(params[:id])
end
def find_coin
#coin = Coin.find(params[:coin_id])
end
def event_params
params.require(:event).permit(:content, :link)
end
end
model:
class Event < ApplicationRecord
belongs_to :user
belongs_to :coin
end
coin model:
class Coin < ApplicationRecord
validates :link_name, :currency_name, presence: true
has_many :questions
has_many :events
end
If anyone has any idea what I may be doing wrong or any tips on how to figure it out, I would really appreciate the assistance.

Answer 1

Making an answer for anyone else who needs it and doesn't read comments :)
When you do:
#event = current_user.events.build(event_params)
You actually create an event related for the user, and it is not related to the coin anymore.
Try to set the coin as well for the event before saving:
#event.coin = #coin
Or you can do it the other way - build the event on the current coin, and then set the user:
#event = #coin.events.build(event_params)
#event.user = current_user
That way - the coin_id will be set automatically because you build an event on that coin.

Answer 2

I have solved the same issue adding 'optional: true' to belongs_to method.
belongs_to :user, optional: true
By default 'belongs_to' require the user_id.
You can use too: 'required: false'.
belongs_to :user, required: false
Good luck.