GraphQL - anime custom feed connection

app/graphql/analysis/max_node_limit.rb

@@ -87,7 +87,7 @@ def max_possible_nodes
 
     # We are checking if a field is a connection or custom type
     def allowed_type?(node, field_definition)
-      return true if field_definition.connection?
+      return true if connection?(field_definition)
       return false if field_definition.name == 'nodes'
       # I am not sure if there is a better way to identify these.
       # but this will get the custom type
@@ -96,8 +96,18 @@ def allowed_type?(node, field_definition)
       false
     end
 
+    def connection?(field_definition)
+      return true if field_definition.connection?
+
+      field_definition.extensions.any? do |extension|
+        # HACK: I am not sure how to handle custom connections
+        # that set connection: false and just use extensions.
+        extension.class.name.downcase.include?('connection')
+      end
+    end
+
     def node_type(node, visitor)
-      prefix = visitor.field_definition.connection? ? 'Connection' : 'Custom'
+      prefix = connection?(visitor.field_definition) ? 'Connection' : 'Custom'
 
       "Analysis::MaxNodeLimit::#{prefix}ScopeType".safe_constantize.new(
         visitor.query,

app/graphql/connections/base_connection.rb

@@ -0,0 +1,2 @@
+class Connections::BaseConnection < GraphQL::Pagination::Connection
+end

app/graphql/connections/feed_item_union_connection.rb

@@ -0,0 +1,47 @@
+class Connections::FeedItemUnionConnection < Connections::BaseConnection
+  attr_reader :mark, :user
+
+  def initialize(items, **args)
+    super(items, args)
+
+    @mark = args[:mark]
+    @user = User.current
+  end
+
+  def nodes
+    @nodes ||= list.to_a
+  end
+
+  def has_next_page
+    @has_next_page = nodes.count == first
+  end
+
+  # There is no backwards check for feeds.
+  def has_previous_page
+    false
+  end
+
+  def cursor_for(item)
+    item&.id
+  end
+
+  private
+
+  def list
+    return @list if @list
+
+    list = items
+    list = list.per(first_value)
+    list = list.page(id_lt: after_value) if after_value
+    list = list.sfw if sfw_filter?
+    list = list.mark if mark
+
+    @list = list
+  end
+
+  def sfw_filter?
+    return true if user.blank?
+
+    user.sfw_filter?
+  end
+end

app/graphql/feed_connection_extension.rb

@@ -0,0 +1,12 @@
+class FeedConnectionExtension < GraphQL::Schema::Field::ConnectionExtension
+  def apply
+    field.argument :first, 'Int', 'Returns the specific amount of elements', required: true
+    field.argument :after, 'String', 'Returns the elements in the list that come after the specified cursor.', required: false
+  end
+
+  def resolve(object:, arguments:, context:)
+    next_args = arguments.dup
+
+    yield(object, next_args)
+  end
+end

app/graphql/kitsu_schema.rb

@@ -4,6 +4,7 @@ class KitsuSchema < GraphQL::Schema
   use GraphQL::Execution::Interpreter
   use GraphQL::Analysis::AST
   use GraphQL::Execution::Errors
+  use GraphQL::Pagination::Connections
 
   default_max_page_size 100
 
@@ -15,6 +16,9 @@ class KitsuSchema < GraphQL::Schema
 
   query_analyzer Analysis::MaxNodeLimit
 
+  # Hook up a custom wrappers
+  connections.add(Types::Union::FeedItem, Connections::FeedItemUnionConnection)
+
   def self.resolve_type(_type, object, _context)
     "Types::#{object.class.name}".safe_constantize
   end

app/graphql/types/anime.rb

@@ -20,4 +20,12 @@ class Types::Anime < Types::BaseObject
   def streaming_links
     AssociationLoader.for(object.class, :streaming_links).scope(object)
   end
+
+  field :feed, Types::Feed,
+    null: false,
+    description: 'The feed for an anime'
+
+  def feed
+    AnimeFeed.new(object.id)
+  end
 end

app/graphql/types/feed.rb

@@ -0,0 +1,16 @@
+class Types::Feed < Types::BaseObject
+  field :activities, Types::Union::FeedItem.connection_type,
+    null: true,
+    connection: false,
+    extensions: [FeedConnectionExtension],
+    description: 'Feed activities based on the type supplied.'
+
+  def activities(first:, after: nil)
+    Connections::FeedItemUnionConnection.new(
+      object.activities,
+      first: first,
+      after: after,
+      context: context
+    )
+  end
+end

app/graphql/types/union/feed_item.rb

@@ -0,0 +1,5 @@
+class Types::Union::FeedItem < Types::Union::Base
+  description 'Objects which are part of a Feed'
+
+  possible_types Types::Post, Types::Profile
+end