Expose an API for reading data

app/connections/clean_connection.rb

@@ -0,0 +1,23 @@
+# This stands in for ActiveFedora::CleanConnection. It behaves the same way,
+# but it doesn't clear the has_model assertion
+class CleanConnection < SimpleDelegator
+  def get(*args)
+    result = __getobj__.get(*args) do |req|
+      prefer_headers = Ldp::PreferHeaders.new(req.headers["Prefer"])
+      prefer_headers.omit = prefer_headers.omit | omit_uris
+      req.headers["Prefer"] = prefer_headers.to_s
+    end
+    result
+  end
+
+  private
+
+    def omit_uris
+      [
+        ::RDF::Vocab::Fcrepo4.ServerManaged,
+        ::RDF::Vocab::LDP.PreferContainment,
+        ::RDF::Vocab::LDP.PreferEmptyContainer,
+        ::RDF::Vocab::LDP.PreferMembership
+      ]
+    end
+end

app/controllers/concerns/curation_concerns/curation_concern_controller.rb

@@ -63,6 +63,7 @@ def show
         render :show, status: :ok
       end
       additional_response_formats(wants)
+      document_export_formats(wants)
     end
   end
 
@@ -179,6 +180,24 @@ def contextual_path(presenter, parent_presenter)
       ::CurationConcerns::ContextualPath.new(presenter, parent_presenter).show
     end
 
+    def document_export_formats(format)
+      format.any do
+        format_name = params.fetch(:format, '').to_sym
+        raise ActionController::UnknownFormat unless presenter.export_formats.include? format_name
+        render_document_export_format format_name
+      end
+    end
+
+    ##
+    # Render the document export formats for a response
+    # First, try to render an appropriate template (e.g. index.endnote.erb)
+    # If that fails, just concatenate the document export responses with a newline.
+    def render_document_export_format(format_name)
+      render
+    rescue ActionView::MissingTemplate
+      render text: presenter.export_as(format_name), layout: false
+    end
+
   private
 
     def curation_concern_from_search_results

app/models/concerns/curation_concerns/solr_document_behavior.rb

@@ -148,5 +148,14 @@ def date_field(field_name)
           Rails.logger.info "Unable to parse date: #{field.first.inspect} for #{self['id']}"
         end
       end
+
+      # This overrides the connection provided by Hydra::ContentNegotiation so we
+      # can get the model too.
+      module ConnectionWithModel
+        def connection
+          # TODO: clean the fedora added triples out.
+          @connection ||= CleanConnection.new(ActiveFedora.fedora.connection)
+        end
+      end
   end
 end

app/presenters/curation_concerns/work_show_presenter.rb

@@ -16,7 +16,7 @@ class WorkShowPresenter
     self.work_presenter_class = self
 
     # Methods used by blacklight helpers
-    delegate :has?, :first, :fetch, to: :solr_document
+    delegate :has?, :first, :fetch, :export_formats, :export_as, to: :solr_document
 
     # @param [SolrDocument] solr_document
     # @param [Ability] current_ability

lib/curation_concerns.rb

@@ -6,4 +6,18 @@
 require 'kaminari_route_prefix'
 
 module CurationConcerns
+  # This method is called once for each statement in the graph.
+  def self.id_to_resource_uri
+    lambda do |id, graph|
+      result = graph.query([nil, ActiveFedora::RDF::Fcrepo::Model.hasModel, nil]).first
+      route_key = result.object.to_s.constantize.model_name.singular_route_key
+      routes = Rails.application.routes.url_helpers
+      builder = ActionDispatch::Routing::PolymorphicRoutes::HelperMethodBuilder
+      builder.polymorphic_method routes, route_key, nil, :url, id: id, host: hostname
+    end
+  end
+
+  def self.hostname
+    config.hostname
+  end
 end

lib/curation_concerns/configuration.rb

@@ -143,6 +143,12 @@ def ingest_queue_name
       @ingest_queue_name ||= :default
     end
 
+    # Hostname is used for the externally visible URI when RDF is requested
+    attr_writer :hostname
+    def hostname
+      @hostname ||= 'localhost'
+    end
+
     callback.enable :after_create_concern, :after_create_fileset,
                     :after_update_content, :after_revert_content,
                     :after_update_metadata, :after_import_local_file_success,

lib/curation_concerns/engine.rb

@@ -50,6 +50,7 @@ class Engine < ::Rails::Engine
         ActiveFedora::Noid.config.template = c.noid_template
         ActiveFedora::Noid.config.statefile = c.minter_statefile
       end
+      Hydra.config.id_to_resource_uri = CurationConcerns.id_to_resource_uri
     end
   end
 end

lib/generators/curation_concerns/install_generator.rb

@@ -80,6 +80,12 @@ def inject_solr_document_behavior
           "\n  # Adds CurationConcerns behaviors to the SolrDocument.\n" \
             "  include CurationConcerns::SolrDocumentBehavior\n"
         end
+
+        insert_into_file file_path, after: /use_extension\(\s*Hydra::ContentNegotiation\s*\)/ do
+          "\n\n  # Overrides the connection provided by Hydra::ContentNegotiation so we" \
+          "\n  # can get the model too." \
+          "\n  use_extension(ConnectionWithModel)"
+        end
       else
         puts "     \e[31mFailure\e[0m  CurationConcerns requires a SolrDocument object. This generators assumes that the model is defined in the file #{file_path}, which does not exist."
       end

lib/generators/curation_concerns/templates/config/curation_concerns.rb

@@ -56,6 +56,9 @@
   # Leaving it blank will set the start date to when ever the file was uploaded by
   # NOTE: if you have always sent analytics to GA for downloads and page views leave this commented out
   # config.analytic_start_date = DateTime.new(2014,9,10)
+
+  # Hostname is used for the externally visible URI when RDF is requested
+  # config.hostname = 'localhost'
 end
 
 Date::DATE_FORMATS[:standard] = '%m/%d/%Y'

spec/controllers/curation_concerns/generic_works_controller_spec.rb

@@ -13,6 +13,7 @@
         get :show, id: a_work
         expect(response).to be_success
       end
+
       context "with a parent work" do
         render_views
         it "renders a breadcrumb" do
@@ -35,10 +36,20 @@
 
     context 'someone elses public work' do
       let(:a_work) { create(:public_generic_work) }
-      it 'shows me the page' do
-        expect(controller). to receive(:additional_response_formats).with(ActionController::MimeResponds::Collector)
-        get :show, id: a_work
-        expect(response).to be_success
+      context "html" do
+        it 'shows me the page' do
+          expect(controller). to receive(:additional_response_formats).with(ActionController::MimeResponds::Collector)
+          get :show, id: a_work
+          expect(response).to be_success
+        end
+      end
+      context "ttl" do
+        it 'renders an turtle file' do
+          get :show, id: a_work, format: :ttl
+          expect(response).to be_successful
+          expect(response.body).to start_with "\n<http://localhost/concern/generic_works/#{a_work.id}>"
+          expect(response.body).to match %r{<http://purl\.org/dc/terms/title> "Test title";}
+        end
       end
     end