Context#container always returns an array.

Author: gkellogg

example-files/implicit-named-graph-example.jsonld

@@ -0,0 +1,30 @@
+{
+  "@context": {
+    "@version": 1.1,
+    "generatedAt": {
+      "@id": "http://www.w3.org/ns/prov#generatedAtTime",
+      "@type": "http://www.w3.org/2001/XMLSchema#date"
+    },
+    "Person": "http://xmlns.com/foaf/0.1/Person",
+    "name": "http://xmlns.com/foaf/0.1/name",
+    "knows": "http://xmlns.com/foaf/0.1/knows",
+    "claim": {
+     "@id": "https://w3id.org/credentials#claim",
+      "@container": "@graph"
+    }
+  },
+  "generatedAt": "2012-04-09",
+  "claim": [
+    {
+      "@id": "http://manu.sporny.org/about#manu",
+      "@type": "Person",
+      "name": "Manu Sporny",
+      "knows": "http://greggkellogg.net/foaf#me"
+    }, {
+      "@id": "http://greggkellogg.net/foaf#me",
+      "@type": "Person",
+      "name": "Gregg Kellogg",
+      "knows": "http://manu.sporny.org/about#manu"
+    }
+  ]
+}

lib/json/ld/compact.rb

@@ -113,7 +113,7 @@ def compact(element, property: nil)
             next
           end
 
-          if expanded_property == '@index' && context.container(property) == '@index'
+          if expanded_property == '@index' && context.container(property) == %w(@index)
             #log_debug("@index") {"drop @index"}
             next
           end
@@ -176,7 +176,7 @@ def compact(element, property: nil)
             # handle @list
             if list?(expanded_item)
               compacted_item = [compacted_item] unless compacted_item.is_a?(Array)
-              unless container == '@list'
+              unless container == %w(@list)
                 al = context.compact_iri('@list', vocab: true, quiet: true)
                 compacted_item = {al => compacted_item}
                 if expanded_item.has_key?('@index')
@@ -191,32 +191,28 @@ def compact(element, property: nil)
             end
 
             # handle simple @graph, not the value of a property with @content: @graph
-            if simple_graph?(expanded_item) && container != '@graph'
+            if simple_graph?(expanded_item) && !container.include?('@graph')
               compacted_item = [compacted_item] unless compacted_item.is_a?(Array)
               al = context.compact_iri('@graph', vocab: true, quiet: true)
               compacted_item = {al => compacted_item}
-              if expanded_item.has_key?('@index')
-                key = context.compact_iri('@index', vocab: true, quiet: true)
-                compacted_item[key] = expanded_item['@index']
-              end
             end
 
-            if container == '@language' || container == '@index' || container == '@id' || container == '@type'
+            if !(container & %w(@language @index @id @type)).empty?
               map_object = nest_result[item_active_property] ||= {}
               compacted_item = case container
-              when '@id'
+              when %w(@id)
                 id_prop = context.compact_iri('@id', vocab: true, quiet: true)
                 map_key = compacted_item[id_prop]
                 map_key = context.compact_iri(map_key, quiet: true)
                 compacted_item.delete(id_prop)
                 compacted_item
-              when '@index'
-                map_key = expanded_item[container]
+              when %w(@index)
+                map_key = expanded_item['@index']
                 compacted_item
-              when '@language'
-                map_key = expanded_item[container]
+              when %w(@language)
+                map_key = expanded_item['@language']
                 value?(expanded_item) ? expanded_item['@value'] : compacted_item
-              when '@type'
+              when %w(@type)
                 type_prop = context.compact_iri('@type', vocab: true, quiet: true)
                 map_key, *types = Array(compacted_item[type_prop])
                 map_key = context.compact_iri(map_key, vocab: true, quiet: true)

lib/json/ld/context.rb

@@ -38,7 +38,7 @@ class TermDefinition
       attr_accessor :type_mapping
 
       # Base container mapping, without @set
-      # @return ['@index', '@language', '@index', '@type', '@id'] Container mapping
+      # @return Array<'@index', '@language', '@index', '@set', '@type', '@id', '@graph'> Container mapping
       attr_reader :container_mapping
 
       # @return [String] Term used for nest properties
@@ -96,7 +96,7 @@ def initialize(term,
         @term                   = term
         @id                     = id.to_s           unless id.nil?
         @type_mapping           = type_mapping.to_s unless type_mapping.nil?
-        self.container_mapping  = container_mapping unless container_mapping.nil?
+        self.container_mapping  = container_mapping
         @language_mapping       = language_mapping  unless language_mapping.nil?
         @reverse_property       = reverse_property
         @nest                   = nest              unless nest.nil?
@@ -112,7 +112,7 @@ def container_mapping=(mapping)
           mapping = mapping.dup
           mapping.delete('@set')
         end
-        @container_mapping = mapping.first
+        @container_mapping = mapping.sort
       end
 
       ##
@@ -143,7 +143,7 @@ def to_context_definition(context)
             end
           end
 
-          cm = [container_mapping, ('@set' if as_set?)].compact
+          cm = (Array(container_mapping) + (as_set? ? %w(@set) : [])).compact
           cm = cm.first if cm.length == 1
           defn['@container'] = cm unless cm.empty?
           # Language set as false to be output as null
@@ -164,8 +164,9 @@ def to_rb
         %w(id type_mapping container_mapping language_mapping reverse_property nest simple prefix context).each do |acc|
           v = instance_variable_get("@#{acc}".to_sym)
           v = v.to_s if v.is_a?(RDF::Term)
-          if acc == 'container_mapping' && as_set?
-            v = v ? [v, '@set'] : '@set'
+          if acc == 'container_mapping'
+            v.concat(%w(@set)) if as_set?
+            v = v.first if v.length <= 1
           end
           defn << "#{acc}: #{v.inspect}" if v
         end
@@ -874,11 +875,11 @@ def find_definition(term)
     # Retrieve container mapping, add it if `value` is provided
     #
     # @param [Term, #to_s] term in unexpanded form
-    # @return [String]
+    # @return [Array<'@index', '@language', '@index', '@set', '@type', '@id', '@graph'>]
     def container(term)
-      return term if KEYWORDS.include?(term)
+      return [term] if KEYWORDS.include?(term)
       term = find_definition(term)
-      term && term.container_mapping
+      term ? term.container_mapping : []
     end
 
     ##
@@ -889,7 +890,7 @@ def container(term)
     def as_array?(term)
       return true if CONTEXT_CONTAINER_ARRAY_TERMS.include?(term)
       term = find_definition(term)
-      term && (term.as_set? || term.container_mapping == '@list')
+      term && (term.as_set? || term.container_mapping.include?('@list'))
     end
 
     ##
@@ -1309,7 +1310,7 @@ def compact_value(property, value, options = {})
 
       num_members = value.length
 
-      num_members -= 1 if index?(value) && container(property) == '@index'
+      num_members -= 1 if index?(value) && container(property).include?('@index')
       if num_members > 2
         #log_debug("") {"can't compact value with # members > 2"}
         return value
@@ -1447,6 +1448,8 @@ def alias(value)
   private
 
     CONTEXT_CONTAINER_ARRAY_TERMS = %w(@set @list @graph).freeze
+    CONTEXT_CONTAINER_ID_GRAPH = %w(@id @graph).freeze
+    CONTEXT_CONTAINER_INDEX_GRAPH = %w(@index @graph).freeze
 
     def uri(value)
       case value.to_s
@@ -1517,7 +1520,8 @@ def inverse_context
         end.each do |term|
           next unless td = term_definitions[term]
 
-          container = td.container_mapping || (td.as_set? ? '@set' : '@none')
+          container = Array(td.container_mapping).sort.first
+          container ||= td.as_set? ? %(@set) : %(@none)
           # FIXME: Alternative to consider
           ## Creates "@language", "@language@set", "@set", or "@none"
           ## for each of "@language", "@index", "@type", "@id", "@list", and "@graph"
@@ -1652,20 +1656,45 @@ def check_container(container, local_context, defined, term)
       val = Array(container).dup
       val.delete('@set') if has_set = val.include?('@set')
 
-      raise JsonLdError::InvalidContainerMapping,
-        "'@container' has more than one value other than @set" if val.length > 1
-
-      case val.first
-      when '@list'
+      if val.include?('@list')
         raise JsonLdError::InvalidContainerMapping,
-          "'@container' on term #{term.inspect} cannot be both @list and @set" if has_set
+          "'@container' on term #{term.inspect} using @list cannot have any other values" unless
+          !has_set && val.length == 1
         # Okay
-      when '@language', '@index', nil
+      elsif val.include?('@language')
+        raise JsonLdError::InvalidContainerMapping,
+              "unknown mapping for '@container' to #{container.inspect} on term #{term.inspect}" if
+               has_set && (processingMode || 'json-ld-1.0') < 'json-ld-1.1'
+        raise JsonLdError::InvalidContainerMapping,
+          "'@container' on term #{term.inspect} using @language cannot have any values other than @set, found  #{container.inspect}" unless
+          val.length == 1
+        # Okay
+      elsif val.include?('@index')
+        raise JsonLdError::InvalidContainerMapping,
+              "unknown mapping for '@container' to #{container.inspect} on term #{term.inspect}" if
+               has_set && (processingMode || 'json-ld-1.0') < 'json-ld-1.1'
+        raise JsonLdError::InvalidContainerMapping,
+          "'@container' on term #{term.inspect} using @index cannot have any values other than @set and/or @graph, found  #{container.inspect}" unless
+          (val - CONTEXT_CONTAINER_INDEX_GRAPH).empty?
         # Okay
-      when '@type', '@id', '@graph', nil
+      elsif val.include?('@id')
         raise JsonLdError::InvalidContainerMapping,
               "unknown mapping for '@container' to #{container.inspect} on term #{term.inspect}" if
                (processingMode || 'json-ld-1.0') < 'json-ld-1.1'
+        raise JsonLdError::InvalidContainerMapping,
+          "'@container' on term #{term.inspect} using @id cannot have any values other than @set and/or @graph, found  #{container.inspect}" unless
+          (val - CONTEXT_CONTAINER_ID_GRAPH).empty?
+        # Okay
+      elsif val.include?('@type') || val.include?('@graph')
+        raise JsonLdError::InvalidContainerMapping,
+              "unknown mapping for '@container' to #{container.inspect} on term #{term.inspect}" if
+               (processingMode || 'json-ld-1.0') < 'json-ld-1.1'
+        raise JsonLdError::InvalidContainerMapping,
+          "'@container' on term #{term.inspect} using @language cannot have any values other than @set, found  #{container.inspect}" unless
+          val.length == 1
+        # Okay
+      elsif val.empty?
+        # Okay
       else
         raise JsonLdError::InvalidContainerMapping,
               "unknown mapping for '@container' to #{container.inspect} on term #{term.inspect}"

lib/json/ld/expand.rb

@@ -23,7 +23,7 @@ def expand(input, active_property, context, ordered: true)
       result = case input
       when Array
         # If element is an array,
-        is_list = context.container(active_property) == '@list'
+        is_list = context.container(active_property) == %w(@list)
         value = input.each_with_object([]) do |v, memo|
           # Initialize expanded item to the result of using this algorithm recursively, passing active context, active property, and item as element.
           v = expand(v, active_property, context, ordered: ordered)
@@ -352,7 +352,7 @@ def expand_object(input, active_property, context, output_object, ordered: false
         term_context = context.term_definitions[key].context if context.term_definitions[key]
         active_context = term_context ? context.parse(term_context) : context
         container = active_context.container(key)
-        expanded_value = if container == '@language' && value.is_a?(Hash)
+        expanded_value = if container == %w(@language) && value.is_a?(Hash)
           # Otherwise, if key's container mapping in active context is @language and value is a JSON object then value is expanded from a language map as follows:
 
           # Set multilingual array to an empty array.
@@ -375,33 +375,33 @@ def expand_object(input, active_property, context, output_object, ordered: false
           end
 
           ary
-        elsif CONTAINER_MAPPING_INDEX_ID_TYPE.include?(container) && value.is_a?(Hash)
-          # Otherwise, if key's container mapping in active context is @index, @id, @type, an IRI or Blank Node and value is a JSON object then value is expanded from an index map as follows:
+        elsif !(CONTAINER_MAPPING_INDEX_ID_TYPE & container).empty? && value.is_a?(Hash)
+          # Otherwise, if key's container mapping in active context contains @index, @id, @type and value is a JSON object then value is expanded from an index map as follows:
 
           # Set ary to an empty array.
-          container, ary = container.to_s, []
+          ary = []
 
           # For each key-value in the object:
           keys = ordered ? value.keys.sort : value.keys
           keys.each do |k|
-            # If container mapping in the active context is @type, and k is a term in the active context having a local context, use that context when expanding values
-            map_context = active_context.term_definitions[k].context if container == '@type' && active_context.term_definitions[k]
+            # If container mapping in the active context includes @type, and k is a term in the active context having a local context, use that context when expanding values
+            map_context = active_context.term_definitions[k].context if container.include?('@type') && active_context.term_definitions[k]
             map_context = active_context.parse(map_context) if map_context
             map_context ||= active_context
 
             # Initialize index value to the result of using this algorithm recursively, passing active context, key as active property, and index value as element.
             index_value = expand([value[k]].flatten, key, map_context, ordered: ordered)
             index_value.each do |item|
               case container
-              when '@index' then item[container] ||= k
-              when '@id'
+              when %w(@index) then item['@index'] ||= k
+              when %w(@id)
                 # Expand k document relative
                 expanded_k = active_context.expand_iri(k, documentRelative: true, quiet: true).to_s
-                item[container] ||= expanded_k
-              when '@type'
+                item['@id'] ||= expanded_k
+              when %w(@type)
                 # Expand k vocabulary relative
                 expanded_k = active_context.expand_iri(k, vocab: true, documentRelative: true, quiet: true).to_s
-                item[container] = [expanded_k].concat(Array(item[container]))
+                item['@type'] = [expanded_k].concat(Array(item['@type']))
               end
 
               # Append item to expanded value.
@@ -422,7 +422,7 @@ def expand_object(input, active_property, context, output_object, ordered: false
         #log_debug {" => #{expanded_value.inspect}"}
 
         # If the container mapping associated to key in active context is @list and expanded value is not already a list object, convert expanded value to a list object by first setting it to an array containing only expanded value if it is not already an array, and then by setting it to a JSON object containing the key-value pair @list-expanded value.
-        if active_context.container(key) == '@list' && !list?(expanded_value)
+        if active_context.container(key) == %w(@list) && !list?(expanded_value)
           #log_debug(" => ") { "convert #{expanded_value.inspect} to list"}
           expanded_value = [expanded_value] unless expanded_value.is_a?(Array)
           expanded_value = {'@list' => expanded_value}
@@ -431,7 +431,7 @@ def expand_object(input, active_property, context, output_object, ordered: false
 
         # convert expanded value to @graph if container specifies it
         # FIXME value may be a named graph, as well as a simple graph.
-        if active_context.container(key) == '@graph' && !graph?(expanded_value)
+        if active_context.container(key) == %w(@graph) && !graph?(expanded_value)
           #log_debug(" => ") { "convert #{expanded_value.inspect} to list"}
           expanded_value = [expanded_value] unless expanded_value.is_a?(Array)
           expanded_value = {'@graph' => expanded_value}