Eager-load and update BasicEnterpriseSerializer

app/controllers/admin/enterprise_relationships_controller.rb

@@ -1,9 +1,13 @@
 module Admin
   class EnterpriseRelationshipsController < ResourceController
     def index
-      @my_enterprises = Enterprise.managed_by(spree_current_user).by_name
-      @all_enterprises = Enterprise.by_name
-      @enterprise_relationships = EnterpriseRelationship.by_name.involving_enterprises @my_enterprises
+      @my_enterprises = Enterprise.
+        includes(:shipping_methods, :payment_methods).
+        managed_by(spree_current_user).by_name
+      @all_enterprises = Enterprise.includes(:shipping_methods, :payment_methods).by_name
+      @enterprise_relationships = EnterpriseRelationship.
+        includes(:parent, :child).
+        by_name.involving_enterprises @my_enterprises
     end
 
     def create

app/serializers/api/admin/basic_enterprise_serializer.rb

@@ -1,4 +1,12 @@
 class Api::Admin::BasicEnterpriseSerializer < ActiveModel::Serializer
   attributes :name, :id, :is_primary_producer, :is_distributor, :sells, :category,
              :payment_method_ids, :shipping_method_ids, :producer_profile_only, :permalink
+
+  def payment_method_ids
+    object.payment_methods.map(&:id)
+  end
+
+  def shipping_method_ids
+    object.shipping_methods.map(&:id)
+  end
 end