GlobalIDでセレクトボックスのグループ化(polymorphic)

Globalid

rails/globalid

irb(main):001:0> dog_gid = Dog.find(1).to_global_id
=> #<GlobalID:0x00007fa353e34588 @uri=#<URI::GID gid://global-id/Dog/1>>

irb(main):002:0> dog_gid.uri
=> #<URI::GID gid://global-id/Dog/1

irb(main):003:0> dog_gid.to_s
=> "gid://global-id/Dog/1"

irb(main):005:0> GlobalID::Locator.locate dog_gid
=> #<Dog id: 1, name: "ハスキー", created_at: "2019-07-06 23:59:43", updated_at: "2019-07-06 23:59:43">

セレクトボックスのグループ化

ポリモーフィックのデータ構造のセレクトボックスのグループ化(grouped_collection_select)に利用してみた

アウトプット(html)

<div class="field">
    <select name="animal[global_target_id]" id="animal_global_target_id">
        <optgroup label="Dog">
            <option value="gid://global-id/Dog/1">ハスキー</option>
            <option value="gid://global-id/Dog/2">ゴールデンレトリバー</option>
            <option value="gid://global-id/Dog/3">コーギー</option>
        </optgroup>
        <optgroup label="Cat">
            <option value="gid://global-id/Cat/1">雑種</option>
            <option value="gid://global-id/Cat/2">スコティッシュ・フォールド</option>
            <option value="gid://global-id/Cat/3">アメリカン・ショートヘア</option>
        </optgroup>
    </select>
</div>

実装

サンプル実装

• model

class Animal < ApplicationRecord
  belongs_to :target, polymorphic: true

  def global_target_id
    self.target.to_global_id.to_s if target.present?
  end

end

class Dog < ApplicationRecord
  has_one :animal, as: :target

  def global_id
    self.to_global_id.to_s
  end

  class << self
    def human_model_name
      model_name.human
    end
  end

end

class Cat < ApplicationRecord
  has_one :animal, as: :target

  def global_id
    self.to_global_id.to_s
  end

  class << self
    def human_model_name
      model_name.human
    end
  end

end

• view

<%= form_with(model: animal, local: true) do |form| %>

  <div class="field">
    <%= form.grouped_collection_select :global_target_id, [Dog, Cat], :all, :human_model_name, :global_id, :name, {}, {} %>
  </div>

  <div class="actions">
    <%= form.submit %>
  </div>
<% end %>

• controller

# POST /animals
# POST /animals.json
def create
  @animal        = Animal.new
  @animal.target = GlobalID::Locator.locate animal_params[:global_target_id]

  respond_to do |format|
    if @animal.save
      format.html { redirect_to @animal, notice: 'Animal was successfully created.' }
      format.json { render :show, status: :created, location: @animal }
    else
      format.html { render :new }
      format.json { render json: @animal.errors, status: :unprocessable_entity }
    end
  end
end