Add support for lambda and callables for allow_include?

Author: lgebhardt

lib/jsonapi/relationship.rb

@@ -102,11 +102,19 @@ def polymorphic_type
         "#{name}_type" if polymorphic?
       end
 
-      def allow_include?
-        if @allow_include.nil?
-          JSONAPI.configuration.default_allow_include_to_one
+      def allow_include?(context = nil)
+        strategy = if @allow_include.nil?
+                     JSONAPI.configuration.default_allow_include_to_one
+                   else
+                     @allow_include
+                   end
+
+        if !!strategy == strategy #check for boolean
+          return strategy
+        elsif strategy.is_a?(Symbol) || strategy.is_a?(String)
+          parent_resource.send(strategy, context)
         else
-          @allow_include
+          strategy.call(context)
         end
       end
     end
@@ -124,12 +132,21 @@ def initialize(name, options = {})
         end
       end
 
-      def allow_include?
-        if @allow_include.nil?
-          JSONAPI.configuration.default_allow_include_to_one
+      def allow_include?(context = nil)
+        strategy = if @allow_include.nil?
+                     JSONAPI.configuration.default_allow_include_to_one
+                   else
+                     @allow_include
+                   end
+
+        if !!strategy == strategy #check for boolean
+          return strategy
+        elsif strategy.is_a?(Symbol) || strategy.is_a?(String)
+          parent_resource.send(strategy, context)
         else
-          @allow_include
+          strategy.call(context)
         end
+
       end
     end
   end

lib/jsonapi/request_parser.rb

@@ -330,7 +330,7 @@ def check_include(resource_klass, include_parts)
 
       relationship = resource_klass._relationship(relationship_name)
       if relationship && format_key(relationship_name) == include_parts.first
-        unless relationship.allow_include?
+        unless relationship.allow_include?(context)
           fail JSONAPI::Exceptions::InvalidInclude.new(format_key(resource_klass._type), include_parts.first)
         end
 

test/unit/resource/relationship_test.rb

@@ -1,5 +1,23 @@
 require File.expand_path('../../../test_helper', __FILE__)
 
+class LambdaBlogPostsResource < JSONAPI::Resource
+  model_name 'Post'
+
+  has_one :author, allow_include: -> (context) { context[:admin] }
+  has_many :comments, allow_include: -> (context) { context[:admin] }
+end
+
+class CallableBlogPostsResource < JSONAPI::Resource
+  model_name 'Post'
+
+  has_one :author, allow_include: :is_admin
+  has_many :comments, allow_include: :is_admin
+
+  def self.is_admin(context)
+    context[:admin]
+  end
+end
+
 class HasOneRelationshipTest < ActiveSupport::TestCase
 
   def test_polymorphic_type
@@ -72,4 +90,21 @@ def test_allow_include_set_overrides_to_config_to_many
   ensure
     JSONAPI.configuration = original_config
   end
+
+  def test_allow_include_set_by_lambda
+    assert LambdaBlogPostsResource._relationship(:author).allow_include?(admin: true)
+    refute LambdaBlogPostsResource._relationship(:author).allow_include?(admin: false)
+
+    assert LambdaBlogPostsResource._relationship(:comments).allow_include?(admin: true)
+    refute LambdaBlogPostsResource._relationship(:comments).allow_include?(admin: false)
+  end
+
+  def test_allow_include_set_by_callable
+    assert CallableBlogPostsResource._relationship(:author).allow_include?(admin: true)
+    refute CallableBlogPostsResource._relationship(:author).allow_include?(admin: false)
+
+    assert CallableBlogPostsResource._relationship(:comments).allow_include?(admin: true)
+    refute CallableBlogPostsResource._relationship(:comments).allow_include?(admin: false)
+  end
+
 end