Add scopes to associations

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When displaying has_many associations, you might want to scope out some associated records. For example, a user might have multiple comments, but on the user's Show page, you don't want to display all the comments, but only the approved ones.

# app/models/comment.rb
class Comment < ApplicationRecord
  belongs_to :user, optional: true

  scope :approved, -> { where(approved: true) }
end

# app/models/user.rb
class User < ApplicationRecord
  has_many :comments
end

# app/avo/resources/user.rb
class Avo::Resources::User < Avo::BaseResource
  def fields
    field :comments, as: :has_many, scope: -> { query.approved }
  end
end

The comments query on the user Index page will have the approved scope attached.

query already holds only the records the user's policy scope allows, so scope narrows the panel further without applying the policy again.

With version 2.5.0, you'll also have access to the parent record so that you can use that to scope your associated models even better.

Starting with version 3.12, access to resource and parent_resource was additionally provided.

All the has_many associations have the attach_scope option available too.