Rails rolling back twice every time I try to post Data - ruby-on-rails

Question

I am trying to create an app that allows users to make lists of items and view only the lists they themselves have created. Every time I press submit on the form this happens
Started POST "/lists" for 127.0.0.1 at 2017-08-18 15:56:40 -0400
Processing by ListsController#create as HTML
Parameters: {"utf8"=>"✓", "authenticity_token"=>"VnsMdQq3mw5XabkYCZFTgvgwFc3H89paHA0VE5gunFbiMfa0xGr0p1GEZDHc3yemwBx07K1h4CXuS0l5XL1VbA==", "list"=>{"income"=>"12", "put_into_savings"=>"12", "month"=>"12", "year"=>"21"}, "commit"=>"Create List"}
(0.1ms) begin transaction
(0.1ms) rollback transaction
(0.0ms) begin transaction
(0.0ms) rollback transaction
Rendering lists/new.html.erb within layouts/application
Rendered lists/new.html.erb within layouts/application (9.3ms)
User Load (0.4ms) SELECT "users".* FROM "users" WHERE "users"."id" = ? LIMIT ? [["id", 5], ["LIMIT", 1]]
Completed 200 OK in 269ms (Views: 222.2ms | ActiveRecord: 2.7ms)
Here is all my code:
lists_controller.rb
class ListsController < ApplicationController
def show
#user = User.find(params[:id])
#lists = #user.lists
end
def new
end
def edit
end
def create
#list = List.create(list_params)
if #list.save
redirect_to home_url
else
render :new
end
end
private
def list_params
params.require(:list).permit(:income, :put_into_savings, :month, :year)
end
end
lists/new.html.erb
<%= form_for List.new do |f| %>
<div class="field">
<%= f.label :income %><br />
<%= f.text_field :income %>
</div>
<div class="field">
<%= f.label :put_into_savings %><br />
<%= f.text_area :put_into_savings %>
</div>
<div class="field">
<%= f.label :month %><br />
<%= f.number_field :month %>
</div>
<div class="field">
<%= f.label :year %><br />
<%= f.number_field :year %>
</div>
<div class="actions">
<%= f.submit %>
</div>
<% end %>
schema.rb
ActiveRecord::Schema.define(version: 20170818185700) do
create_table "items", force: :cascade do |t|
t.string "item_name"
t.integer "item_cost"
t.string "item_waste"
t.string "item_group"
t.datetime "created_at", null: false
t.datetime "updated_at", null: false
end
create_table "lists", force: :cascade do |t|
t.integer "income"
t.integer "put_into_savings"
t.string "month"
t.string "year"
t.datetime "created_at", null: false
t.datetime "updated_at", null: false
t.integer "Item_id"
t.integer "User_id"
end
create_table "users", force: :cascade do |t|
t.string "email"
t.string "password_digest"
t.datetime "created_at", null: false
t.datetime "updated_at", null: false
t.string "name"
end
end
Routes.rb
Rails.application.routes.draw do
root 'home#index'
get 'home' => 'home#index'
resources :lists
resources :sessions, only: [:new, :create, :destroy]
resources :users, only: [:new, :create]
# For details on the DSL available within this file, see http://guides.rubyonrails.org/routing.html
end
Here is my list model:
class List < ApplicationRecord
has_many :items
belongs_to :user
end
How can I solve this?

Answer 1

You are having logic problem with your model association.
Assuming that a List could have more than one Item, you shouldn't have declared your table List with the attribute item_id. (Doing that it means a List could ONLY have one item). I recommend you read ruby-on-rais-guide-for-associations.
For the problem with the user_id, you need to explicit declared the user_id in your list object (considering that you want to associate a List with a User in the moment the List is created). One way to do it could be:
def create
#list = List.new(list_params)
#list[:user_id] = current_user.id # Considering you add this method
if #list.save
redirect_to home_url
else
render :new
end
And add some validation in model:
class List < ApplicationRecord
has_many :items
belongs_to :user
validates :user_id, presence: true
end
It seems you need to read more about validation too ruby-on-rais-guide-for-validation. About your twice rollback, it is unclear the reason, but fixing you association and validations problems, I think you can fix it.
Try read more about rails, the problem you are having are really basic. Good luck!
UPDATE:
As suggested by at0misk answer, to solve the problem with twice rollback:
In List controller:
#list = List.new(list_params)
# instead of #list = List.create(list_params)
The create method create a new object and save immediately. So, rails was trying to save twice, in the method create first, then in the method save in sequence.

Answer 2

In your create method, you're calling create and then calling save. Create creates an object and saves it to the database, so calling save is redundent.
Have you checked to see if your record is saving? If it is then this is definitely what's wrong. I prefer to use this pattern, using new instead of create, and then attempting to save in an if block:
def create
#list = List.new(list_params)
if #list.save
redirect_to home_url
else
render :new
end
end