Merge pull request #3 from samvera-labs/hyku_1372_rendering

Support for a 'sequence_rendering' method

README.md

@@ -5,11 +5,17 @@ IIIF http://iiif.io/ defines an API for presenting related images in a viewer. T
 
 ## Usage
 
-You application must have an object that implements `#file_set_presenters` and `#work_presenters`.  The former method should return as set of leaf nodes and the later any interstitial nodes. If none are found an empty array should be returned. Additionally it should implement `#manifest_url` that shows where the manifest can be found. Finally, it must have a `#description` method that returns a string.
+Your application ***must*** have an object that implements `#file_set_presenters` and `#work_presenters`.  The former method should return as set of leaf nodes and the later any interstitial nodes. If none are found an empty array should be returned. 
+
+Additionally, it ***must*** have a `#description` method that returns a string.
+
+Additionally it ***should*** implement `#manifest_url` that shows where the manifest can be found. 
+
+Finally, it ***may*** implement `#sequence_rendering` to contain an array of hashes for file downloads to be offered at sequences level. Each hash must contain "@id", "format" (mime type) and "label" (eg. `{ "@id" => "download url", "format" => "application/pdf", "label" => "user friendly label" }`). 
 
 For example:
 
-```ruby
+ ```ruby
   class Book
     def initialize(id, pages = [])
       @id = id
@@ -31,6 +37,10 @@ For example:
     def description
       'a brief description'
     end
+
+    def sequence_rendering:
+      [{"@id" => "http://test.host/file_set/id/download", "format" => "application/pdf", "label" => "Download"}]
+    end
   end
 ```
 

lib/iiif_manifest/manifest_builder/sequence_builder.rb

@@ -28,10 +28,19 @@ def sequence
           begin
             sequence = IIIF::Presentation::Sequence.new
             sequence['@id'] ||= work.manifest_url + '/sequence/normal'
+            sequence['rendering'] ||= populate_sequence_rendering
             canvas_builder.apply(sequence)
             sequence
           end
       end
+
+      def populate_sequence_rendering
+        if work.respond_to?(:sequence_rendering)
+          work.sequence_rendering.each(&:to_h)
+        else
+          []
+        end
+      end
     end
   end
 end

spec/lib/iiif_manifest/manifest_factory_spec.rb

@@ -76,6 +76,59 @@ def display_image
       end
     end
 
+    context 'where there is a no sequence_rendering method' do
+      let(:file_presenter) { DisplayImagePresenter.new }
+
+      it 'does not have a rendering on the sequence' do
+        allow(IIIFManifest::ManifestBuilder::CanvasBuilder).to receive(:new).and_call_original
+        allow(book_presenter).to receive(:file_set_presenters).and_return([file_presenter])
+        expect(result['sequences'][0]['rendering']).to eq []
+      end
+    end
+
+    context 'where there is a sequence_rendering method' do
+      let(:file_presenter) { DisplayImagePresenter.new }
+
+      before do
+        class Book
+          def initialize(id)
+            @id = id
+          end
+
+          def description
+            'a brief description'
+          end
+
+          def file_set_presenters
+            []
+          end
+
+          def work_presenters
+            []
+          end
+
+          def manifest_url
+            "http://test.host/books/#{@id}/manifest"
+          end
+
+          def sequence_rendering
+            [{ '@id' => 'http://test.host/file_set/id/download',
+               'format' => 'application/pdf',
+               'label' => 'Download' }]
+          end
+        end
+      end
+
+      it 'has a rendering on the sequence' do
+        allow(IIIFManifest::ManifestBuilder::CanvasBuilder).to receive(:new).and_call_original
+        allow(book_presenter).to receive(:file_set_presenters).and_return([file_presenter])
+
+        expect(result['sequences'][0]['rendering']).to eq [{
+          '@id' => 'http://test.host/file_set/id/download', 'format' => 'application/pdf', 'label' => 'Download'
+        }]
+      end
+    end
+
     context 'when there are child works' do
       let(:child_work_presenter) { presenter_class.new('test2') }