find_publication_by_identifier.rb

# Wings (aka ActiveFedora) specific implementation that finds a publication given its unique identifier.
module CustomQueries
  module Wings
    class FindPublicationByIdentifier
      # Define the queries that can be fulfilled by this custom query.
      def self.queries
        [:find_publication_by_identifier]
      end

      attr_reader :query_service
      delegate :resource_factory, to: :query_service

      def initialize(query_service:)
        @query_service = query_service
      end

      ##
      # Find by identifier (e.g. slug_id)
      # @param identifier [String] agency identifier (e.g. slug_id, other string assigned by agency)
      # @return [Array<Valkyrie::Resource>]
      def find_publication_by_identifier(identifier:)
        af_find_publication_by_identifier(identifier: identifier)
      end

      private

        # Find by identifier (e.g. slug_id)
        # @param identifier [String] agency identifier (e.g. slug_id, other string assigned by agency)
        # @return [Array<Valkyrie::Resource>]
        # @raise [Hyrax::ObjectNotFoundError]
        def af_find_publication_by_identifier(identifier:)
          results = Publication.where(identifier: [identifier])
          raise Hyrax::ObjectNotFoundError, "Publication with identifier '#{identifier}' not found." unless results.count.positive?
          resource_factory.to_resource(object: results.first)
        rescue ActiveFedora::ObjectNotFoundError, Ldp::Gone
          raise Hyrax::ObjectNotFoundError, "Publication with identifier '#{identifier}' not found." unless results.count.positive?
        end
    end
  end
end