Support RO-Crate spec 1.2

README.md

@@ -2,10 +2,10 @@
 
 ![Tests](https://github.com/ResearchObject/ro-crate-ruby/actions/workflows/tests.yml/badge.svg)
 
-This is a WIP gem for creating, manipulating and reading RO-Crates (conforming to version 1.1 of the specification).
+This is a WIP gem for creating, manipulating and reading RO-Crates (conforming to version 1.2 of the specification). RO-Crates produced by older versions (1.0, 1.1) of the spec can still be read.
 
-* RO-Crate - https://researchobject.github.io/ro-crate/
-* RO-Crate spec (1.1) - https://researchobject.github.io/ro-crate/1.1/
+* RO-Crate - https://www.researchobject.org/ro-crate/
+* RO-Crate spec (1.2) - https://www.researchobject.org/ro-crate/specification/1.2/
 
 ## Installation
 

lib/ro_crate/model/crate.rb

@@ -21,9 +21,18 @@ def self.format_local_id(id)
 
     ##
     # Initialize an empty RO-Crate.
-    def initialize(id = IDENTIFIER, properties = {})
+    #
+    # @param id [String] The crate's identifier.
+    # @param properties [Hash] Initial properties for the root data entity.
+    # @param version [String] RO-Crate spec version to declare (default: ROCrate::Metadata::DEFAULT_VERSION).
+    #   Must be one of ROCrate::Metadata::SUPPORTED_VERSIONS.
+    def initialize(id = IDENTIFIER, properties = {}, version: ROCrate::Metadata::DEFAULT_VERSION)
+      unless ROCrate::Metadata::SUPPORTED_VERSIONS.include?(version)
+        raise ArgumentError, "Unsupported RO-Crate version: #{version.inspect}. Supported: #{ROCrate::Metadata::SUPPORTED_VERSIONS.join(', ')}"
+      end
       @data_entities = Set.new
       @contextual_entities = Set.new
+      @metadata_version = version
       super(self, nil, id, properties)
     end
 
@@ -168,7 +177,7 @@ def add_data_entity(entity)
     #
     # @return [Metadata]
     def metadata
-      @metadata ||= ROCrate::Metadata.new(self)
+      @metadata ||= ROCrate::Metadata.new(self, {}, version: @metadata_version || ROCrate::Metadata::DEFAULT_VERSION)
     end
 
     ##

lib/ro_crate/model/metadata.rb

@@ -5,13 +5,31 @@ class Metadata < File
     IDENTIFIER = 'ro-crate-metadata.json'.freeze
     IDENTIFIER_1_0 = 'ro-crate-metadata.jsonld'.freeze # 1.0 spec identifier
     RO_CRATE_BASE = 'https://w3id.org/ro/crate/'
-    CONTEXT = "#{RO_CRATE_BASE}1.1/context".freeze
-    SPEC = "#{RO_CRATE_BASE}1.1".freeze
 
-    def initialize(crate, properties = {})
+    SUPPORTED_VERSIONS = %w[1.0 1.0-DRAFT 1.1 1.1-DRAFT 1.2 1.2-DRAFT].freeze
+    DEFAULT_VERSION = '1.2'.freeze
+
+    CONTEXT = "#{RO_CRATE_BASE}#{DEFAULT_VERSION}/context".freeze
+    SPEC = "#{RO_CRATE_BASE}#{DEFAULT_VERSION}".freeze
+
+    attr_reader :version
+
+    def initialize(crate, properties = {}, version: DEFAULT_VERSION)
+      unless SUPPORTED_VERSIONS.include?(version)
+        raise ArgumentError, "Unsupported RO-Crate version: #{version.inspect}. Supported: #{SUPPORTED_VERSIONS.join(', ')}"
+      end
+      @version = version
       super(crate, nil, IDENTIFIER, properties)
     end
 
+    def context_url
+      "#{RO_CRATE_BASE}#{@version}/context"
+    end
+
+    def spec_url
+      "#{RO_CRATE_BASE}#{@version}"
+    end
+
     ##
     # Generate the crate's `ro-crate-metadata.jsonld`.
     # @return [String] The rendered JSON-LD as a "prettified" string.
@@ -21,7 +39,7 @@ def generate
     end
 
     def context
-      @context || CONTEXT
+      @context || context_url
     end
 
     def context= c
@@ -39,7 +57,7 @@ def default_properties
         '@id' => IDENTIFIER,
         '@type' => 'CreativeWork',
         'about' => { '@id' => crate.id },
-        'conformsTo' => { '@id' => SPEC }
+        'conformsTo' => { '@id' => spec_url }
       }
     end
   end

lib/ro_crate/reader.rb

@@ -266,7 +266,7 @@ def self.create_data_entity(crate, entity_class, source, entity_props)
 
     ##
     # Extract the metadata entity from the entity hash, according to the rules defined here:
-    # https://www.researchobject.org/ro-crate/1.1/root-data-entity.html#finding-the-root-data-entity
+    # https://www.researchobject.org/ro-crate/specification/1.2/root-data-entity.html#finding-the-root-data-entity
     # @return [nil, Hash{String => Hash}] A Hash containing (hopefully) one value, the metadata entity's properties
     # mapped by its @id, or nil if nothing is found.
     def self.extract_metadata_entity(entities)
@@ -294,7 +294,7 @@ def self.extract_preview_entity(entities)
 
     ##
     # Extract the root entity from the entity hash, according to the rules defined here:
-    # https://www.researchobject.org/ro-crate/1.1/root-data-entity.html#finding-the-root-data-entity
+    # https://www.researchobject.org/ro-crate/specification/1.2/root-data-entity.html#finding-the-root-data-entity
     # @return [Hash{String => Hash}] A Hash containing (hopefully) one value, the root entity's properties,
     # mapped by its @id.
     def self.extract_root_entity(entities)

test/crate_test.rb

@@ -377,4 +377,24 @@ class CrateTest < Test::Unit::TestCase
     assert_nil crate.get('#joe')
     assert crate.get('#joehouse')
   end
+
+  test 'defaults to RO-Crate spec 1.2' do
+    crate = ROCrate::Crate.new
+    assert_equal '1.2', crate.metadata.version
+    assert_equal 'https://w3id.org/ro/crate/1.2/context', crate.metadata.context
+    assert_equal 'https://w3id.org/ro/crate/1.2', crate.metadata.spec_url
+    assert_equal({ '@id' => 'https://w3id.org/ro/crate/1.2' }, crate.metadata.properties['conformsTo'])
+  end
+
+  test 'can write older spec version' do
+    crate = ROCrate::Crate.new(ROCrate::Crate::IDENTIFIER, {}, version: '1.1')
+    assert_equal '1.1', crate.metadata.version
+    assert_equal 'https://w3id.org/ro/crate/1.1/context', crate.metadata.context
+    assert_equal({ '@id' => 'https://w3id.org/ro/crate/1.1' }, crate.metadata.properties['conformsTo'])
+  end
+
+  test 'rejects unsupported spec version' do
+    assert_raise(ArgumentError) { ROCrate::Crate.new(ROCrate::Crate::IDENTIFIER, {}, version: '1.5') }
+    assert_raise(ArgumentError) { ROCrate::Crate.new(ROCrate::Crate::IDENTIFIER, {}, version: 'v1.2') }
+  end
 end