create link class

lib/fast_jsonapi/link.rb

@@ -0,0 +1,29 @@
+module FastJsonapi
+  class Link
+    attr_reader :key, :method, :conditional_proc
+
+    def initialize(key:, method:, options: {})
+      @key = key
+      @method = method
+      @conditional_proc = options[:if]
+    end
+
+    def serialize(record, serialization_params, output_hash)
+      if include_link?(record, serialization_params)
+        output_hash[key] = if method.is_a?(Proc)
+          method.arity == 1 ? method.call(record) : method.call(record, serialization_params)
+        else
+          record.public_send(method)
+        end
+      end
+    end
+
+    def include_link?(record, serialization_params)
+      if conditional_proc.present?
+        conditional_proc.call(record, serialization_params)
+      else
+        true
+      end
+    end
+  end
+end

lib/fast_jsonapi/object_serializer.rb

@@ -5,6 +5,7 @@ require 'active_support/concern'
 require 'active_support/inflector'
 require 'fast_jsonapi/attribute'
 require 'fast_jsonapi/relationship'
+require 'fast_jsonapi/link'
 require 'fast_jsonapi/serialization_core'
 
 module FastJsonapi
@@ -238,11 +239,16 @@ module FastJsonapi
         {}
       end
 
-      def link(link_name, link_method_name = nil, &block)
+      def link(link_name, link_method_name = nil, options = {}, &block)
         self.data_links = {} if self.data_links.nil?
         link_method_name = link_name if link_method_name.nil?
         key = run_key_transform(link_name)
-        self.data_links[key] = block || link_method_name
+
+        self.data_links[key] = Link.new(
+          key: key,
+          method: block || link_method_name,
+          options: options
+        )
       end
 
       def validate_includes!(includes)

lib/fast_jsonapi/serialization_core.rb

@@ -35,18 +35,14 @@ module FastJsonapi
       end
 
       def links_hash(record, params = {})
-        data_links.each_with_object({}) do |(key, method), link_hash|
-          link_hash[key] = if method.is_a?(Proc)
-            method.arity == 1 ? method.call(record) : method.call(record, params)
-          else
-            record.public_send(method)
-          end
+        data_links.each_with_object({}) do |(_k, link), hash|
+          link.serialize(record, params, hash)
         end
       end
 
       def attributes_hash(record, params = {})
-        attributes_to_serialize.each_with_object({}) do |(key, attribute), attr_hash|
-          attribute.serialize(record, params, attr_hash)
+        attributes_to_serialize.each_with_object({}) do |(_k, attribute), hash|
+          attribute.serialize(record, params, hash)
         end
       end