Grape route metaprogramming

comments.rb

# frozen_string_literal: true

module API
  module Client
    class Comments < Grape::API
      [Post, Profile, Story].each do |model|
        namespace model.table_name do
          route_param :ref, type: String do
            namespace :comments do
              desc "List comments for #{model.name.downcase}"
              params do
                optional :per_page, type: Integer, default: 10
                optional :page, type: Integer, default: 1
              end
              get do
                commentable = find(model, ref: params[:ref])
                present :comments, paginate(commentable.comments)
              end

              desc "Create comment in #{model.name.downcase}"
              params do
                requires :body, type: String
              end
              post do
                commentable = find(model, ref: params[:ref])

                comment = commentable.comments.create!(author_id: params[:_user_id], body: params[:body])
                MentionProcessingWorker.perform_async(comment.id, comment.base_class_name, :body)

                present :comment, comment
              end
            end
          end
        end
      end

      namespace :comments do
        route_param :id, type: Integer do
          desc 'Edit comment'
          params do
            requires :body, type: String
          end
          put do
            comment = find(Comment, id: params[:id])
            forbidden! unless comment.author_id == params[:_user_id]

            comment.update!(body: params[:body], edited: true)
            MentionProcessingWorker.perform_async(comment.id, comment.base_class_name, :body)

            present :comment, comment
          end
        end
      end
    end
  end
end