Rails create dynamic attributes - ruby-on-rails

I'm trying to make e-commerce shop with RoR. Most of the required functionality I did without any problems, but now I really need somebody's help here.
I want to make product attributes, like a "Size", "Weight", "Color", etc.
Easiest way is to define this attributes in model migration, but now I want to make attributes dynamic. The main problem is that I can't get all params with attributes from forms when trying to create product.
products/new.html.erb
<%= form_for #product, url: admin_products_path(#product) do |f| %>
<%= f.label :name, 'Name' %>
<%= f.text_field :name, class: "form-control" %>
<%= text_field_tag "product[product_feature][]" %>
<%= text_field_tag "product[product_feature][]" %>
<%= f.submit "Submit" %>
<% end %>
So, I want to generate many fields with attribute name and value, fill them and use these params in controller to interate them and finally create product attributes.
Like
params[:product_features].each do |k, v|
ProductFeature.create(name: k, value: v, product_id: product_id)
end
All gems, that can manipulate with dynamic attributes aren't working with Rails 5+, so I need to find solution for this problem.
I even have working simple db solution for this, but it's uncomfortable to create params. Here it is.
Product.rb
class Product < ApplicationRecord
has_many :product_features
has_many :features, :through => :product_features
end
ProductFeature.rb
class ProductFeature < ApplicationRecord
belongs_to :product
belongs_to :feature
end
Feature.rb
class Feature < ApplicationRecord
end

Make a new model, a child of product called ProductAttribute with two attributes.
Class ProductAttribute < ApplicationRecord
belongs_to :product
validates :name, presence: true
validates :value, presence: true
end
Then use cocoon, or just accepts_nested_attributes
class Product < ApplicationRecord
has_many :product_attributes, as: :attributes
accepts_nested_attributes_for :attributes, allow_destroy: true
end
class ProductsController < ApplicationController
.
.
.
private
.
.
def product_params
params.require(:product).permit(. . . attributes_attributes: [:id, :name, :value])
end
end
Cocoon is definitely what you're looking for.

Heres a quick example i found
class Product
belongs_to :collection
end
class Collection
has_many :products
end
and then in your view something like this
<%= collection_select(:product, :collection_id, Collection.all, :id, :name) %>

Related

Rails has_many :through nested forms with simple form

I am trying to make a player character generator. I have a form that hopefully will allow me to attach skills with their values to a character sheet model. I made models like this:
class CharacterSheet < ApplicationRecord
has_many :character_sheet_skills, dependent: :destroy
has_many :skills, through: :character_sheet_skills
belongs_to :user
accepts_nested_attributes_for :skills
end
class Skill < ApplicationRecord
has_many :character_sheet_skills, dependent: :destroy
has_many :character_sheets, through: :character_sheet_skills
attr_reader :value
end
class CharacterSheetSkill < ApplicationRecord
belongs_to :skill
belongs_to :character_sheet
end
Character sheet model holds data about player character and skill model has all skills available in game. In CharacterSheetSkill I'd like to store the skills that the player chooses for his character together with an integer field setting the skill value.
When opening form, I already have a full list of skills in database. All I want to do in form is create a character sheet that has all of these skills with added value. I tried using "fields_for" in form, but I couldn't really get that to work. Right now it looks like this:
<%= simple_form_for [#user, #sheet] do |f| %>
<%= f.input :name %>
<%= f.input :experience, readonly: true, input_html: {'data-target': 'new-character-sheet.exp', class: 'bg-transparent'} %>
...
<%= f.simple_fields_for :skills do |s| %>
<%= s.input :name %>
<%= s.input :value %>
<% end %>
<% end %>
How can I make that form so it saves character sheet together with CharacterSheetSkills?
A better idea here is to use skills as a normalization table where you store the "master" definition of a skill such as the name and the description.
class CharacterSheetSkill < ApplicationRecord
belongs_to :skill
belongs_to :character_sheet
delegate :name, to: :skill
end
You then use fields_for :character_sheet_skills to create rows on the join table explicitly:
<%= f.fields_for :character_sheet_skills do |cs| %>
<fieldset>
<legend><%= cs.name %></legend>
<div class="field">
<%= cs.label :value %>
<%= cs.number_field :value %>
</div>
<%= cs.hidden_field :skill_id %>
</fieldset>
<% end %>
Instead of a hidden fields you could use a select if you want let the user select the skills.
Of course nothing will show up unless you "seed" the inputs:
class CharacterSheetController < ApplicationController
def new
#character_sheet = CharacterSheet.new do |cs|
# this seeds the association so that the fields appear
Skill.all.each do |skill|
cs.character_sheet_skills.new(skill: skill)
end
end
end
def create
#character_sheet = CharacterSheet.new(character_sheet_params)
if #character_sheet.save
redirect_to #character_sheet
else
render :new
end
end
private
def character_sheet_params
params.require(:character_sheet)
.permit(
:foo, :bar, :baz,
character_sheet_skill_attributes: [:skill_id, :value]
)
end
end

Rails nested form with unknown columns

I'm creating an admin interface where the admin (of a company) can add custom fields to their employees.
Example:
Models:
Employee: Basic info like name, contact info, etc (has_many employee_field_values)
EmployeeFields: These are the dynamic ones the admin can add (every company has different needs, it could be anything), lets say favorite_food
EmployeeFieldValues: The actual values based on the fields above, say pizza (belongs_to both models above)
What's a smart way of adding the EmployeeFieldValues fields while editing an employee?
I'm trying something simple like this, but not sure if I like it
# Controller
#custom_fields = EmployeeFields.all
# View
<%= form_for(#employee) do |f| %>
<%= f.text_field :first_name %>
<% #custom_fields.each do |custom_field| %>
<%= custom_field.name %>
<%= text_field_tag "employee_field_values[#{custom_field.name}]" %>
<% end %>
<%= f.submit :save %>
<% end %>
And then when updating, params[:employee_field_values] gives this:
<ActionController::Parameters {"favorite_food"=>"pizza"}>
So, not sure if this is a good direction, also I'm not sure how to handle future edits to an employee's custom_fields if they change.
I think it will be better to use EmployeeField as nested model and EmployeeFieldValue for select field.
For example:
Models
class Employee < ActiveRecord::Base
validates :name, presence: true
has_many :employee_field_values
accepts_nested_attributes_for :employee_field_values, reject_if: ->(x) { x[:value].blank? }
end
class EmployeeFieldValue < ActiveRecord::Base
belongs_to :employee
belongs_to :employee_field
end
class EmployeeField < ActiveRecord::Base
has_many :employee_field_values, inverse_of: :employee_field, dependent: :destroy
validates :title, presence: true, uniqueness: true
end
Controller
class EmployeesController < ApplicationController
def new
#employee = Employee.new
#employee.employee_field_values.build
end
end
View
= simple_form_for #employee, url: '/' do |f|
= f.input :name
= f.simple_fields_for :employee_field_values do |ff|
= ff.input :value
= ff.input :employee_field_id, collection: EmployeeField.all.map{|x| [x.title, x.id]}
Also you need to make buttons for adding/removing :employee_field_value, and you can do it with gem cocoon for example
OR you can build all objects in controller(for each EmployeeField) and do without select box

Rails form multiple checkboxes for associated model

I'm creating an application where a "submission" can be made using a form which creates client details and allows "referrals" to be created depending on the branch(es) that can provide the required service
class Submission < ActiveRecord::Base
has_many :referrals, :inverse_of => :submission, dependent: :delete_all
accepts_nested_attributes_for :referrals, :allow_destroy => true
end
class Referral < ActiveRecord::Base
belongs_to :submission
end
class Branch < ActiveRecord::Base
has_many :referrals
end
Submissions controller:
def new
#submission = Submission.new
#submission.build_client
#submission.client.build_address
#submission.referrals.build
end
def submission_params
params.require(:submission).permit(:consent, :user_id, client_attributes:
[:client_id, :first_name,
address_attributes:
[:first_line, :second_line,]
],
referrals_attributes:
[:branch_id]
)
end
The Submission form:
<%= form_for(#submission) do |f| %>
<%= f.fields_for :referrals do |referral| %>
<%= render 'referral_fields', f: referral %>
<% end %>
<% end %>
_referral_fields.html.erb:
<% Branch.all.where(referrable: true).each do |branch| %>
<label>
<%= check_box_tag 'branch_ids[]', branch.id %>
<%= branch.name %>
</label>
<% end %>
What I want is to have checkboxes for each referrable branch. When a branch is ticked and the submission is created, a referral will be created for that branch. However, when I submit the form, I get a validation error of "Referrals can't be blank". Any idea why this is not working?
Any help is most appreciated
Use collection_check_boxes.
<% # _referral_fields.html.erb %>
<%= f.collection_check_boxes(:branch_ids, Branch.where(referrable: true), :id, :name) do |b|
b.label { b.check_box } # wraps check box in label
end %>
You would need to whitelist submission[referrals_attributes][branch_ids] - not branch_id.
def submission_params
params.require(:submission)
.permit(
:consent,
:user_id,
client_attributes: [
:client_id,
:first_name,
address_attributes: [
:first_line, :second_line,
]
],
referrals_attributes: [:branch_ids]
)
end
Edited.
However for this to work you need to setup a relation between Referral and Branch. In this case you could use either a has_and_belongs_to_many (HABTM) or has_many though: (HMT) relationship.
See Choosing Between has_many :through and has_and_belongs_to_many.
class Referral < ActiveRecord::Base
belongs_to :submission
has_and_belongs_to_many :branches
end
class Branch < ActiveRecord::Base
has_and_belongs_to_many :referrals
end
You need to create a join table as well:
rails g migration CreateBranchReferralJoinTable branch referral

Nested Attributes for a Rich Join Table, using simple_form Rails

I want to create a form that has nested attributes, which populates a record within a rich join table. (That created record within the rich join table of course should have the appropriate foreign keys.)
I have yet to find a thorough answer on creating nested form fields on a has_many :through relationship. Please help!
For this example, I have a user form. Within that form, I am also trying to populate a record within the users_pets table (rich join table).
Additional question: are rich join models supposed to be singular or plural? Example: app/models/owners_pets.rb or app/models/owners_pet.rb.
app/models/owner.rb
class Owner < ActiveRecord::Base
has_many :owners_pets, allow_destroy: true
has_many :pets, through: :owners_pets
end
app/models/pet.rb
class Pet < ActiveRecord::Base
has_many :owners_pets, allow_destroy: true
has_many :owners, through: :owners_pets
end
app/models/owners_pets.rb
class OwnersPet < ActiveRecord::Base
belongs_to :owners
belongs_to :pets
end
app/controller/owners.rb
def owner_params
params.require(:owner).permit(:first_name, owners_pets_attributes: [:id, :pet_name, :pet_id])
end
app/views/owners/_form.html.erb
<%= simple_form_for(#owner) do |f| %>
<%= f.input :first_name %>
<%= f.simple_fields_for :owners_pets do |ff|
<%= ff.input :pet_name %>
<% end %>
<div>
<%= f.button :submit %>
</div>
<% end %>
Here is the answer, thanks to a bunch of help from a mentor. It helps me to keep in mind that rich join naming conventions should NOT be pluralized at the very end, just like other non-rich-join models. Ex: book_page.rb NOT books_pages.rb. Even books_page.rb would work (just update your strong params and database table accordingly). The important part is that the entire model must follow the rails convention of the model being singular (no 's' on the end).
Below in the rich join model, I made the decision to name it the completely singular version: owner_pet.rb as opposed to the other version: owners_pet.rb. (Therefore of course, my database table is named: owner_pets)
app/models/owner.rb
class Owner < ActiveRecord::Base
has_many :owner_pets
has_many :pets, through: :owner_pets
accepts_nested_attributes_for :owner_pets, allow_destroy: true
end
app/models/pet.rb
class Pet < ActiveRecord::Base
has_many :owner_pets
has_many :owners, through: :owner_pets
end
app/models/owner_pet.rb
class OwnerPet < ActiveRecord::Base
belongs_to :owner
belongs_to :pet
end
app/controller/owners.rb
def new
#owner = Owner.new
#owner.owner_pets.build
end
private
def owner_params
params.require(:owner).permit(:first_name, owner_pets_attributes: [:_destroy, :id, :pet_name, :pet_id, :owner_id])
end
app/views/owners/_form.html.erb
<%= simple_form_for(#owner) do |f| %>
<%= f.input :first_name %>
<%= f.simple_fields_for :owner_pets do |ff| %>
<%= ff.input :pet_name %>
<%= ff.input :pet_id, collection: Pet.all, label_method: "pet_type" %>
<% end %>
<div>
<%= f.button :submit %>
</div>
<% end %>
Your join table is the problem:
It should be belongs_to :owners belongs_to :pets for the join table to work
Plus the rich join model should be pluralised, as in: owners_pets

Nested forms with multiple table inheritance

How do I build a nested form for objects using multiple table inheritance in rails? I am trying to make a nested form to create an object using a model with a has_many relationship to another set of models that feature multi-table inheritance. I am using formtastic and cocoon for the nested form and the act_as_relation gem to implement the multiple table inheritance.
I have the following models:
class Product < ActiveRecord::Base
acts_as_superclass
belongs_to :store
end
class Book < ActiveRecord::Base
acts_as :product, :as => :producible
end
class Pen < ActiveRecord::Base
acts_as :product, :as => :producible acts_as :product, :as => :producible
end
class Store < ActiveRecord::Base
has_many :products
accepts_nested_attributes_for :products, :allow_destroy => true, :reject_if => :all_blank
end'
For this example, the only unique attribute that book has compared to other products is an author field. In reality, I have a number of unique attributes for book which is why I chose multi-table inheritance over the more commonplace single table inheritance.
I am trying to create a nested form that allows you to create a new store with products. Here's my form:
<%= semantic_form_for #store do |f| %>
<%= f.inputs do %>
<%= f.input :name %>
<h3>Books/h3>
<div id='books'>
<%= f.semantic_fields_for :books do |book| %>
<%= render 'book_fields', :f => book %>
<% end %>
<div class='links'>
<%= link_to_add_association 'add book', f, :books %>
</div>
<% end %>
<%= f.actions :submit %>
<% end %>
And the book_fields partial:
<div class='nested-fields'>
<%= f.inputs do %>
<%= f.input :author %>
<%= link_to_remove_association "remove book", f %>
<% end %>
</div>
I get this error:
undefined method `new_record?' for nil:NilClass
Based on reading the issues on the github page for act_as_relation, I thought about making the relationship between store and books more explicit:
class Product < ActiveRecord::Base
acts_as_superclass
belongs_to :store
has_one :book
accepts_nested_attributes_for :book, :allow_destroy => true, :reject_if => :all_blank
end
class Book < ActiveRecord::Base
belongs_to :store
acts_as :product, :as => :producible
end
class Store < ActiveRecord::Base
has_many :products
has_many :books, :through => :products
accepts_nested_attributes_for :products, :allow_destroy => true, :reject_if => :all_blank
accepts_nested_attributes_for :books, :allow_destroy => true, :reject_if => :all_blank
end
Now, I get a silent error. I can create new stores using the form, and cocoon allows me to add new book fields, but when I submit the store gets created but not the child book. When, I go through the `/books/new' route, I can create a new book record that spans (the products and books table) with no problem.
Is there a workaround to this problem? The rest of the code can be found here.
Maybe you could:
Build the books relation manually on your stores_controller#new action
#store.books.build
Store manually the relation on you stores_controller#create action
#store.books ... (not really confident on how to achieve it)
Keep us posted.
You might want to consider creating your own form object. This is a RailsCast pro video, but here are some of the examples in the ASCIIcast:
def new
#signup_form = SignupForm.new(current_user)
end
This signup form can include relations to your other objects, just as you would in your original controller code:
class SignupForm
# Rails 4: include ActiveModel::Model
extend ActiveModel::Naming
include ActiveModel::Conversion
include ActiveModel::Validations
validates_presence_of :username
validates_uniqueness_of :username
validates_format_of :email, with: /\A([^#\s]+)#((?:[-a-z0-9]+\.)+[a-z]{2,})\Z/
validates_length_of :password, minimum: 6
def persisted?
false
end
def subscribed
subscribed_at
end
def subscribed=(checkbox)
subscribed_at = Time.zone.now if checkbox == "1"
end
def generate_token
begin
self.token = SecureRandom.hex
end while User.exists?(token: token)
end
end
Here is the link to the RailsCast. Getting a pro membership might be worth your time. I have been getting lucky with a membership through www.codeschool.com where you can get 'prizes' when you finish courses:
RailsCast:
http://railscasts.com/episodes/416-form-objects

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