Best practice in creating belongs_to object - ruby-on-rails

Let's say we have the following situation:
class User < ActiveRecord::Base
has_many :tickets
end
class Ticket < ActiveRecord::Base
belongs_to :user
end
For simplicity let's say Ticket has only some text field description and integer user_id. If we open User's views/users/show.html.erb view and inside User controller we have this code which finds correct user which is selected:
def show
#user = User.find(params[:id])
end`
Now inside that show.html.erb view we also have small code snipped which creates user's ticket. Would this be a good practice in creating it?
views/users/show.html.erb
<%= simple_form_for Ticket.new do |f| %>
<%= f.hidden_field :user_id, :value => #user.id %>
<%= f.text_area :description %>
<%= f.submit "Add" %>
<% end %>
controller/tickets_controller.rb
def create
#ticket = Ticket.new(ticket_params)
#user = User.find(ticket_params[:user_id])
#ticket.save
end
def ticket_params
params.require(:ticket).permit(:user_id, :description)
end
So, when we create a ticket for user, ticket's description and his user_id (hidden field inside view) are passed to tickets_controller.rb where new Ticket is created.
Is this a good practice in creating a new object which belongs to some other object? I am still learning so I would like to make this clear :) Thank you.

You should be able to do something like this in your form:
<%= f.association :user, :as => :hidden, :value => #user.id %>
This will pass user_id through your controller to your model and automatically make an association. You no longer need the #user= line in your controller.
Don't forget that the user could modify the form on their end and send any id they want. :)
See https://github.com/plataformatec/simple_form#associations for more info.

How about getting the user from the controller using current_user so that you protect yourself from anyone that would manipulate the value of the user_id in the form. Also I think this way is much cleaner
views/users/show.html.erb
<%= simple_form_for Ticket.new do |f| %>
<%= f.text_area :description %>
<%= f.submit "Add" %>
<% end %>
controller/tickets_controller.rb
def create
#ticket = Ticket.new(ticket_params)
#ticket.user = current_user
#ticket.save
end
def ticket_params
params.require(:ticket).permit(:user_id, :description)
end

Related

Difficulty saving form information to the database

I've been trying to implement a commenting system for a blog application I've been working on. However, I've been having a lot of difficulty getting my form to save inputted information to my database.
The code for my comment's controller is:
def create
#comment = #wad.comments.create(comment_params)
if #comment.save
flash[:sucess] = "Thanks for posting!"
redirect_to wad_comments_path(#wad)
else
flash[:error] = "Failed submission. Please try again."
render 'index'
end
end
.
.
.
private
def comment_params
params.require(:comment).permit(:content)
end
The code for my model:
class Comment < ApplicationRecord
attr_accessor :content
belongs_to :wad
belongs_to :user
end
and the code for my form:
<%= form_for([#wad, #wad.comments.create]) do |f| %>
<%= f.text_area :content %>
<%= f.submit %>
<% end %>
Where "wad" is a regular post. I've checked my server log, and in the params is a :comment hash containing :content. I'm not sure why, then, it's not saving to the database. Any thoughts?
why you are using attr_accessor :content instead use column and modify following line
<%= form_for([#wad, #wad.comments.create]) do |f| %>
as
<%= form_for([#wad, #wad.comments.build]) do |f| %>

Using form_for with "becomes" loses child association

When building out a form that handles STI, if I use becomes to transform the object to its parent class, I lose the ability to use nested fields with it.
I have two models
class Login < ActiveRecord::Base
belongs_to :user
end
class User < ActiveRecord::Base
has_one :login
accepts_nested_attributes_for :login
end
I also have a few subclasses of User.
class Consumer < User
end
class Admin < User
end
class Agent < User
end
Initially I had problems with the routing, since Rails would assume that I wanted a route specific to the current class rather than the parent class, so I used #user.becomes(User), which is apparently the way to handle that. For the most part it works fine, however this causes #user.login to disappear.
Controller
class Admin::UsersController < AdminController
load_and_authorize_resource
before_filter :authenticate_user!
def index
render 'index'
end
def new
#user = User.new
#user.build_login
render 'new'
end
def create
#user = User.new(user_params)
if #user.save
flash[:notice] = "Account confirmation instructions sent to #{#user.login.email}"
redirect_to new_user_path
else
flash.now[:error] = #user.errors.full_messages.to_sentence
# At this point, I can confirm that #user.login still exists...
render 'new'
end
end
private
def user_params
params.require(:user).permit(
:type,
:dealership_id,
login_attributes: [
:email
])
end
end
Here's the most relevant form view bit
<%= simple_form_for(#user.becomes(User), html: {class: "user-form"}) do |f| %>
<%= f.simple_fields_for :login do |l| %>
<div class="field">
<%= l.label :email %><br />
<%= l.email_field :email %>
</div>
<% end %>
<div class="field">
<%= f.label :type %>
<%= f.select :type, options_for_select(current_user.types_can_create), include_blank: "- Select -", class: "form-control", id: "select_type" %>
</div>
<div class="actions">
<%= f.submit "Register" %>
</div>
<% end %>
The text field for :email doesn't display because #user.login is now nil. Is this expected behavior when using becomes?
Having only used becomes once before, I can only attest to my scant experience -- whenever you use it, it essentially invokes a new instance of the class.
I'm not sure as to the specifics, but the bottom line is that I would surmise that your #user.becomes(User) is overriding #user.build_login...
Returns an instance of the specified klass with the attributes of the current record.
--
In your case, I would set the path explicitly (as you're using User anyway):
<%= simple_form_for #user, url: user_path, method: :post html: {class: "user-form"} do |f| %>
In Rails 5, this can be solved with
<%= form_with scope: :user,
model: #user,
url: #user.id ? user_path(user) : users_path,
local: true do |f| %>
...
...
<% end %>
The previous code instructs the FormBuilder to fill in the fields with the #user attributes, but it also instructs it to submit to the main route (not the inherited ones) and, with scope:, it also instructs it to name the fields using the User class name, not the child class names.

Create parent object in child create method

There are many related question on SO. I went through all of them but still struggle with my situation.
I have two models User and Booking
#model/user.rb
has_many :bookings
#modle/booking.rb
belongs_to :user
I want to create a booking and a user at the same time. If the user already exist, just add the new booking to the existing user.
My form for creating booking:
<%= simple_form_for :booking, url: bookings_path, :method => :post, do |f| %>
<%= f.fields_for :user, do |ff| %>
<%= ff.input_field :first_name %>
<%= ff.input_field :last_name %>
<%= ff.input_field :email %>
<%= ff.input_field :phone %>
<% end %>
...
<% end %>
And in the booking controller
#control/bookings_controller.rb
def create
#user = User.find_by(:email => booking_params[:user][:email])
if #user == nil
#user = User.new(booking_params[:user])
#user.username = User.autousername(#user)
#user.password = Devise.firendly_token(8)
else
#user.update(booking_params[:user])
end
#user.save
b_params = booking_params
b_params.delete("user")
#booking = Booking.new(b_params)
#booking.user_id = #user.id
#booking.save
...
end
def booking_params
params.require(:booking).permit(:status, :house_id, :check_in, :check_out, :adult_guest, :children_guest, :temp_profit,
:note, :check_in_note, :user => [:first_name, :last_name, :email, :phone])
end
I didn't use nested_attributes because I want to generate username and password myself rather than collect them using form.
What I got is ActiveRecord::AssociationTypeMismatch in BookingsController#create
User(#70121505047640) expected, got ActionController::Parameters(#70121556154400)
Most SO related problems want to create the child object under parent controller. In my case, it's reversed.
UPDATE
After trying every possible way, I found out that the CanCanCan load_and_authorize_resource seems to be the trouble maker. If I comment out it in my bookings_controller, everything works fine. Could someone tell me why?
Solution
Finally, I found out the reason. I'm using CanCanCan load_and_authorize_resource in my booking_controller. In order to create nested user instance under it, I have to load user resources. Just add load_and_authorize_resource :user will solve the problem!
Thanks for all the answers. Hope this will help people with the same problem.
This is probably happening when you try to do the #booking.save. Because you have a user param, it will try to use the user= to set it. In this case, the user= will apply a params object.
Try to delete the user param from the booking_params when you create the booking.
b_params.delete(:user)
or
b_params[:user] = #user

Rails Nested Form Not Saving Nested Attributes

I have the following User controller:
class UsersController < ApplicationController
def index
#users = User.all
end
def new
#user = User.new
end
def create
#user = User.new(user_params)
#customer = Customer.new
if #user.save
flash.notice = "User '#{#user.email}' was succefully created."
redirect_to user_path(#user)
else
render 'new'
end
end
def show
#user = User.find(params[:id])
end
private
def user_params
params.require(:user).permit(:email, :password, :password_confirmation, customer_attributes: [:id, :company])
end
end
And I have the following User model:
class User < ActiveRecord::Base
has_one :customer
accepts_nested_attributes_for :customer, :allow_destroy => true
end
And the following Customer model:
class Customer < ActiveRecord::Base
belongs_to :user
end
Finally, here is the form:
<%= form_for [#user] do |f| %>
<% if #user.errors.any? %>
<div id="error_explanation">
<h2><%= pluralize(#user.errors.count, "error") %> prohibited this user from being saved:</h2>
<ul>
<% #user.errors.full_messages.each do |msg| %>
<li><%= msg %></li>
<% end %>
</ul>
</div>
<% end %>
<div class="field">
<%= f.label :email %><br>
<%= f.text_field :email %>
</div>
<div class="field">
<%= f.label :password %><br>
<%= f.password_field :password %>
</div>
<div class="field">
<%= f.label :password_confirmation %><br>
<%= f.password_field :password_confirmation %>
</div>
<%= f.fields_for :customers do |company| %>
<div class="field">
<%= company.label :company %><br>
<%= company.text_field :company %>
</div>
<% end %>
<div class="actions">
<%= f.submit %>
</div>
<% end %>
When I submit the form, I see: `Unpermitted parameters: customers' in the log but it appears that I m indeed permitting it.
Also, I want to show the company name for each user in the show and index views. I'm not sure how to do that.
I remember using the build method in the past to get something similar to work but I can't seem to figure it out this time.
Further to #Mandeep's answer, let me give you some further information:
You need to "build" your associated objects for your form
You need to process this as per the association your model has
You need to save the attributes as per said association
The way to do this is relatively simple (outlined by Mandeep). However, the reason why might be a little less obvious:
Build
First, you need to build your associative association. This is vitally important, primarily because Rails (by virtue of being built on Ruby), is an object orientated framework.
Object orientation, without getting into too much detail, means that everything you do with Rails is going to be based around objects. In the case of our beloved Rails, it means that every Model is an object.
By virtue of this fact, the nested model paradigm has to be built in Rails whenever you want to create such a form. To do this, you need to use the build methods - which tell ActiveRecord (Rails' object relational mapper) that you have another associated model / object which you want to populate:
#app/controllers/users_controller.rb
class UsersController < ApplicationController
def new
#user = User.new #-> initializes "User" object
#user.build_customer #-> "builds" the associated object
end
end
This gives Rails a set of associated data which it can populate with your form (considering you call the correct methods)
--
Association
Second, you need to consider the association you have. This is important as singular & multiple associations are handled differently in the "build" process.
You're using a has_one relationship, which means you need to use singular association names (although you can call the associations whatever you want):
If you used a has_many association, you'd need to use the plural association methods:
This explains the need to use the build_customer method; but also should give you the presidence to use the singular association name for all the methods you need to get this working, namely fields_for and params:
#app/views/users/new.html.erb
<%= form_for #user do |f| %>
...
<%= f.fields_for :customer do |c| %>
...
<% end %>
<%= f.submit %>
<% end %>
#app/controllers/users_controller.rb
class UsersController < ApplicationController
def create
#user = User.new user_params
#user.save
end
private
def user_params
params.permit(:user).permit(:user, :params, customer_attributes: [:x. :y])
end
end
--
Save
The above controller code will save the attributes you require.
You must understand that passing nested attributes means that the model you're sending the associative data to needs to be subordinated to your "main" model. This happens with the ActiveRecord associations in your models, as discussed initially.
Hopefully this gives you some more clarity
Change your code to this:
def new
#user = User.new
#user.build_customer
end
your form:
<%= form_for #user do |f| %>
// user fields
<%= f.fields_for :customer do |customer| %>
// customer fields
<% end %>
<% end %>
Also there is not need of #customer = Customer.new in your create method.

How to get Rails build and fields_for to create only a new record and not include existing?

I am using build, fields_for, and accepts_nested_attributes_for to create a new registration note on the same form as a new registration (has many registration notes). Great.
Problem: On the edit form for the existing registration, I want another new registration note to be created, but I don't want to see a field for each of the existing registration notes.
I have this
class Registration < ActiveRecord::Base
attr_accessible :foo, :bar, :registration_notes_attributes
has_many :registration_notes
accepts_nested_attributes_for :registration_notes
end
and this
class RegistrationsController < ApplicationController
def edit
#registration = Registration.find(params[:id])
#registration.registration_notes.build
end
end
and in the view I am doing this:
<%= form_for #registration do |r| %>
<%= r.text_field :foo %>
<%= r.text_field :bar %>
<%= r.fields_for :registration_notes do |n| %>
<%= n.text_area :content %>
<% end %>
<% end %>
and it is creating a blank text area for a new registration note (good) and each existing registration note for that registration (no thank you).
Is there a way to only create a new note for that registration and leave the existing ones alone?
EDIT: My previous answer (see below) was bugging me because it's not very nice (it still loops through all the other registration_notes needlessly). After reading the API a bit more, the best way to get the behaviour the OP wanted is to replace:
<%= r.fields_for :registration_notes do |n| %>
with:
<%= r.fields_for :registration_notes, #registration.registration_notes.build do |n| %>
fields_for optionally takes a second parameter which is the specific object to pass to the builder (see the API), which is built inline. It's probably actually better to create and pass the new note in the controller instead of in the form though (just to move the logic out of the view).
Original answer (I was so close):
Just to clarify, you want your edit form to include a new nested registration note (and ignore any other existing ones)? I haven't tested this, but you should be able to do so by replacing:
<%= r.fields_for :registration_notes do |n| %>
with:
<%= r.fields_for #registration.registration_notes.build do |n| %>
EDIT: Okay, from a quick test of my own that doesn't work, but instead you can do:
<%= r.fields_for :registration_notes do |n| %>
<%= n.text_area :content if n.object.id.nil? %>
<% end %>
This will only add the text area if the id of the registration note is nil (ie. it hasn't been saved yet).
Also, I actually tested this first and it does work ;)
If you want to create a new registration form on your edit action, you can just instantiate a new registration_note object. Right now, your form is for the existing registration object.
I believe this is what you want:
class RegistrationsController < ApplicationController
def edit
#new_registration_note = RegistrationNote.new
#registration = Registration.find(params[:id])
#registration.registration_notes.build
end
end
In your view, you should pass a hidden param that references the registration record id:
<%= form_for #new_registration_note do |r| %>
<%= r.hidden_field :registration_id, :value => #registration.id %>
<%= r.text_area :content %>
<% end %>
Now, you can create your new registration note that belongs to #registration. Make sure you have a column in your registration_notes table to point to the registration. You can read more about associations here: http://guides.rubyonrails.org/association_basics.html
Thank you so much for your help as I said in my post the only problem with the approach from "Zaid Crouch"(I don't know how to make a reference to a user hehe) is that if the form has error fields the form will be clear and boom after the page reloading you'll have nothing filled in your form and can you imagine if you form is like 20 or 30 fields that would be a terrible user experience of course
Here is my solution that works with validation models:
class Registration < ActiveRecord::Base
attr_accessible :foo, :bar, :registration_notes_attributes
has_many :registration_notes
has_one :new_registration, class_name: 'RegistrationNote'
accepts_nested_attributes_for :new_registration
end
class RegistrationsController < ApplicationController
def edit
#registration = Registration.find(params[:id])
#registration.build_new_registration
end
end
<%= form_for #registration do |r| %>
<%= r.text_field :foo %>
<%= r.text_field :bar %>
<%= r.fields_for :new_registration do |n| %>
<%= n.text_area :content %>
<% end %>
<% end %>
I'm using simple_form in my example if you want to see the same working with validations and transaction take a look at the complete post here:
http://elh.mx/ruby/using-simple_form-for-nested-attributes-models-in-a-has_many-relation-for-only-new-records/
As Heriberto Perez correctly pointed out the solution in the most upvoted answer will simply discard everything if there's a validation error on one of the fields.
My approach is similar to Heriberto's but nevertheless a bit different:
Model:
class Registration < ActiveRecord::Base
has_many :registration_notes
accepts_nested_attributes_for :registration_notes
# Because 0 is never 1 this association will never return any records.
# Above all this association don't return any existing persisted records.
has_many :new_registration_notes, -> { where('0 = 1') }
, class_name: 'RegistrationNote'
accepts_nested_attributes_for :new_registration_notes
end
Controller:
class RegistrationsController < ApplicationController
before_action :set_registration
def edit
#registration.new_registration_notes.build
end
private
def set_registration
#registration = Registration.find(params[:id])
end
def new_registration_params
params.require(:registration).permit(new_registrations_attributes: [:content])
end
end
View:
<%= form_for #registration do |r| %>
<%= r.text_field :foo %>
<%= r.text_field :bar %>
<%= r.fields_for :new_registration_notes do |n| %>
<%= n.text_area :content %>
<% end %>
<% end %>

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