Merge pull request #1131 from beauby/jsonapi-include-tree

Extended format for JSONAPI `include` option

lib/active_model/serializer.rb

@@ -10,6 +10,7 @@ module ActiveModel
     autoload :Lint
     autoload :Associations
     autoload :Fieldset
+    autoload :Utils
     include Configuration
     include Associations
 

lib/active_model/serializer/adapter/json_api.rb

@@ -7,11 +7,7 @@ class ActiveModel::Serializer::Adapter::JsonApi < ActiveModel::Serializer::Adapt
           super
           @hash = { data: [] }
 
-          @options[:include] ||= []
-          if @options[:include].is_a?(String)
-            @options[:include] = @options[:include].split(',')
-          end
-
+          @included = ActiveModel::Serializer::Utils.include_args_to_hash(@options[:include])
           fields = options.delete(:fields)
           if fields
             @fieldset = ActiveModel::Serializer::Fieldset.new(fields, serializer.json_key)
@@ -117,48 +113,38 @@ class ActiveModel::Serializer::Adapter::JsonApi < ActiveModel::Serializer::Adapt
         end
 
         def included_for(serializer)
-          serializer.associations.flat_map { |assoc| _included_for(assoc.key, assoc.serializer) }.uniq
+          included = @included.flat_map do |inc|
+            association = serializer.associations.find { |assoc| assoc.key == inc.first }
+            _included_for(association.serializer, inc.second) if association
+          end
+
+          included.uniq
         end
 
-        def _included_for(resource_name, serializer, parent = nil)
+        def _included_for(serializer, includes)
           if serializer.respond_to?(:each)
-            serializer.flat_map { |s| _included_for(resource_name, s, parent) }.uniq
+            serializer.flat_map { |s| _included_for(s, includes) }.uniq
           else
             return [] unless serializer && serializer.object
-            result = []
-            resource_path = [parent, resource_name].compact.join('.')
 
-            if include_assoc?(resource_path)
-              primary_data = primary_data_for(serializer, @options)
-              relationships = relationships_for(serializer)
-              primary_data[:relationships] = relationships if relationships.any?
-              result.push(primary_data)
-            end
+            primary_data = primary_data_for(serializer, @options)
+            relationships = relationships_for(serializer)
+            primary_data[:relationships] = relationships if relationships.any?
 
-            if include_nested_assoc?(resource_path)
-              non_empty_associations = serializer.associations.select(&:serializer)
+            included = [primary_data]
 
-              non_empty_associations.each do |association|
-                result.concat(_included_for(association.key, association.serializer, resource_path))
-                result.uniq!
+            includes.each do |inc|
+              association = serializer.associations.find { |assoc| assoc.key == inc.first }
+              if association
+                included.concat(_included_for(association.serializer, inc.second))
+                included.uniq!
               end
             end
-            result
+
+            included
           end
         end
 
-        def include_assoc?(assoc)
-          check_assoc("#{assoc}$")
-        end
-
-        def include_nested_assoc?(assoc)
-          check_assoc("#{assoc}.")
-        end
-
-        def check_assoc(assoc)
-          @options[:include].any? { |s| s.match(/^#{assoc.gsub('.', '\.')}/) }
-        end
-
         def add_links(options)
           links = @hash.fetch(:links) { {} }
           collection = serializer.object

lib/active_model/serializer/utils.rb

@@ -0,0 +1,35 @@
+module ActiveModel::Serializer::Utils
+  module_function
+
+  # Translates a comma separated list of dot separated paths (JSONAPI format) into a Hash.
+  # Example: `'posts.author, posts.comments.upvotes, posts.comments.author'` would become `{ posts: { author: {}, comments: { author: {}, upvotes: {} } } }`.
+  #
+  # @param [String] included
+  # @return [Hash] a Hash representing the same tree structure
+  def include_string_to_hash(included)
+    included.delete(' ').split(',').inject({}) do |hash, path|
+      hash.deep_merge!(path.split('.').reverse_each.inject({}) { |a, e| { e.to_sym => a } })
+    end
+  end
+
+  # Translates the arguments passed to the include option into a Hash. The format can be either
+  # a String (see #include_string_to_hash), an Array of Symbols and Hashes, or a mix of both.
+  # Example: `posts: [:author, comments: [:author, :upvotes]]` would become `{ posts: { author: {}, comments: { author: {}, upvotes: {} } } }`.
+  #
+  # @param [Symbol, Hash, Array, String] included
+  # @return [Hash] a Hash representing the same tree structure
+  def include_args_to_hash(included)
+    case included
+    when Symbol
+      { included => {} }
+    when Hash
+      included.each_with_object({}) { |(key, value), hash| hash[key] = include_args_to_hash(value) }
+    when Array
+      included.inject({}) { |a, e| a.merge!(include_args_to_hash(e)) }
+    when String
+      include_string_to_hash(included)
+    else
+      {}
+    end
+  end
+end