Rails and Validation - ruby-on-rails-3

Question

I'm still (for those that have helped before) having issues validating data.
The Scenario
I have two models - user and accommodation with each user having one accommodation (has_one). I am able to access the logged in user using current_user.
The Problem
When I validate users upon registration everything works fine with validation error messages displayed accordingly for each validation rule. However, I am now trying to validate accommodations when they are entered and I get a Rails error page:
Unknown Action
The action 'show' could not be found for AccommodationsController
but interestingly the url has changed to /accommodations//edit which appears to be missing an id for the accommodations id (I do want it to divert to edit if everything is ok).
I don't think it's the validation rules themselves but more how I am handling redirection (which is confusing me to be honest!). The data saves correctly and redirects correctly if it passes the validation rules but not sure how to handle a "non-save" gracefully.
The Code
Accommodation Model
class Accommodation < ActiveRecord::Base
belongs_to :user
#validation rules
validates :user_id, presence: true
validates :name, presence: true, length: { maximum: 50 }
VALID_EMAIL_REGEX = /\A[\w+\-.]+#[a-z\d\-.]+\.[a-z]+\z/i
validates :email, presence: true, format: { with: VALID_EMAIL_REGEX }, uniqueness: { case_sensitive: false }
end
/accommodations/new.html.erb
...
<%= form_for :accommodation, url: accommodations_path do |f| %>
<% if #accommodation.errors.any? %>
<% #accommodation.errors.full_messages.each do |msg| %>
<p class="error"><%= msg %></p>
<% end %>
<% end %>
...
AccommodationsController (thanks to #depa for help with this)
...
def index
if current_user.accommodation.present?
redirect_to edit_accommodation_path(current_user.accommodation)
else
redirect_to new_accommodation_path(current_user.accommodation)
end
end
def new
#accommodation = Accommodation.new
end
def create
current_user.create_accommodation(accommodation_params)
flash[:success] = "Accommodation details added"
redirect_to edit_accommodation_path(current_user.accommodation)
end
def edit
end
def update
if #accommodation.update(accommodation_params)
flash[:success] = "Accommodation details updated successfully"
redirect_to edit_accommodation_path(#accommodation)
else
flash[:error] = "Accommodation details could not be updated"
render 'edit'
end
end
private
def accommodation_params
params.require(:accommodation).permit(:name, :email)
end
...

Answer 1

To handle your failed validations gracefully:
def create
#accommodation = current_user.build_accommodation(accommodation_params)
if #accommodation.save
flash[:success] = "Accommodation details added"
redirect_to edit_accommodation_path(current_user.accommodation)
else
flash.now.notice = "Error creating accommodation"
render "new"
end
end

Answer 2

Is accommodation_params actually set up on entry to create? I'd expect you to need to use params or params[:accommodation].
If it isn't, the create_accommodation call is going to fail, which will mean current_user.accommodation will be nil, which may well produce your error.