From aafe132c9beacd487d859d2d674ee5268c22a49a Mon Sep 17 00:00:00 2001
From: Vivek <vivekmiyaniofficial@gmail.com>
Date: Sat, 15 Jun 2024 01:01:11 +0530
Subject: [PATCH] Add PreloadExtension

---
 lib/phantom/graphql.rb                  |  5 +++-
 lib/phantom/graphql/authorization.rb    | 23 -----------------
 lib/phantom/graphql/field_extensions.rb | 34 +++++++++++++++++++++++++
 phantom.gemspec                         |  2 +-
 4 files changed, 39 insertions(+), 25 deletions(-)
 delete mode 100644 lib/phantom/graphql/authorization.rb
 create mode 100644 lib/phantom/graphql/field_extensions.rb

diff --git a/lib/phantom/graphql.rb b/lib/phantom/graphql.rb
index 2756ed9..3039eb8 100644
--- a/lib/phantom/graphql.rb
+++ b/lib/phantom/graphql.rb
@@ -1,14 +1,17 @@
 # frozen_string_literal: true
 
 require "graphql"
+require "batch-loader"
 
 module Phantom::Graphql
 end
 
-require "phantom/graphql/authorization"
+require "phantom/graphql/field_extensions"
 require "phantom/graphql/enum"
 require "phantom/graphql/response"
 
+GraphQL::Schema.use(BatchLoader::GraphQL)
+
 GraphQL::Schema::InputObject.extend(Phantom::Graphql::Enum)
 GraphQL::Schema::Object.extend(Phantom::Graphql::Enum)
 GraphQL::Schema::RelayClassicMutation.extend(Phantom::Graphql::Enum)
diff --git a/lib/phantom/graphql/authorization.rb b/lib/phantom/graphql/authorization.rb
deleted file mode 100644
index da9e170..0000000
--- a/lib/phantom/graphql/authorization.rb
+++ /dev/null
@@ -1,23 +0,0 @@
-# frozen_string_literal: true
-
-module Phantom::Graphql::Authorization
-  class AuthorizeExtension < GraphQL::Schema::FieldExtension
-    def resolve(context:, object:, arguments:, **_rest)
-      name, action = options.split("#")
-
-      authorized = name.constantize.new(context[:current_session]).send(action)
-
-      raise GraphQL::ExecutionError, "Unauthorized" unless authorized
-
-      yield object, arguments
-    end
-  end
-
-  def initialize(*args, authorize: nil, **kwargs, &block)
-    extensions = (kwargs[:extensions] ||= [])
-
-    extensions << { Phantom::Graphql::Authorization::AuthorizeExtension => authorize } if authorize.present?
-
-    super(*args, **kwargs, &block)
-  end
-end
diff --git a/lib/phantom/graphql/field_extensions.rb b/lib/phantom/graphql/field_extensions.rb
new file mode 100644
index 0000000..161c9f5
--- /dev/null
+++ b/lib/phantom/graphql/field_extensions.rb
@@ -0,0 +1,34 @@
+# frozen_string_literal: true
+
+module Phantom::Graphql::FieldExtensions
+  class AuthorizeExtension < GraphQL::Schema::FieldExtension
+    def resolve(context:, object:, arguments:, **_rest)
+      name, action = options.split("#")
+
+      authorized = name.constantize.new(context[:current_session]).send(action)
+
+      raise GraphQL::ExecutionError, "Unauthorized" unless authorized
+
+      yield object, arguments
+    end
+  end
+
+  class PreloadExtension < GraphQL::Schema::FieldExtension
+    def resolve(context:, object:, arguments:, **rest)
+      BatchLoader::GraphQL.for(object).batch(key: field) do |records, loader|
+        scope = options[:scope].constantize.new(context[:current_session]).scope if options[:scope].present?
+        ActiveRecord::Associations::Preloader.new(records: records.map(&:object), associations: options[:preload]).call
+        records.each { |r| loader.call(r, super(context: context, object: r, arguments: arguments, **rest)) }
+      end
+    end
+  end
+
+  def initialize(*args, authorize: nil, preload: nil, scope: nil, **kwargs, &block)
+    extensions = (kwargs[:extensions] ||= [])
+
+    extensions << { Phantom::Graphql::FieldExtensions::AuthorizeExtension => authorize } if authorize.present?
+    extensions << { Phantom::Graphql::FieldExtensions::PreloadExtension => { preload: preload, scope: scope } } if preload.present?
+
+    super(*args, **kwargs, &block)
+  end
+end
diff --git a/phantom.gemspec b/phantom.gemspec
index fe7041f..3082791 100644
--- a/phantom.gemspec
+++ b/phantom.gemspec
@@ -14,6 +14,6 @@ Gem::Specification.new do |s|
   s.metadata["rubygems_mfa_required"] = "true"
 
   s.required_ruby_version = ">= 3.1"
+  s.add_dependency "batch-loader"
   s.add_dependency "graphql"
-  s.add_dependency "minitest"
 end