1 files changed, 73 insertions, 0 deletions

diff --git a/app/graphql/mutations/discussions/toggle_resolve.rb b/app/graphql/mutations/discussions/toggle_resolve.rb
new file mode 100644
index 00000000000..41fd22c6b55
--- /dev/null
+++ b/app/graphql/mutations/discussions/toggle_resolve.rb
@@ -0,0 +1,73 @@
+# frozen_string_literal: true
+
+module Mutations
+  module Discussions
+    class ToggleResolve < BaseMutation
+      graphql_name 'DiscussionToggleResolve'
+
+      description 'Toggles the resolved state of a discussion'
+
+      argument :id,
+                GraphQL::ID_TYPE,
+                required: true,
+                description: 'The global id of the discussion'
+
+      argument :resolve,
+               GraphQL::BOOLEAN_TYPE,
+               required: true,
+               description: 'Will resolve the discussion when true, and unresolve the discussion when false'
+
+      field :discussion,
+            Types::Notes::DiscussionType,
+            null: true,
+            description: 'The discussion after mutation'
+
+      def resolve(id:, resolve:)
+        discussion = authorized_find_discussion!(id: id)
+        errors = []
+
+        begin
+          if resolve
+            resolve!(discussion)
+          else
+            unresolve!(discussion)
+          end
+        rescue ActiveRecord::RecordNotSaved
+          errors << "Discussion failed to be #{'un' unless resolve}resolved"
+        end
+
+        {
+          discussion: discussion,
+          errors: errors
+        }
+      end
+
+      private
+
+      # `Discussion` permissions are checked through `Discussion#can_resolve?`,
+      # so we use this method of checking permissions rather than by defining
+      # an `authorize` permission and calling `authorized_find!`.
+      def authorized_find_discussion!(id:)
+        find_object(id: id).tap do |discussion|
+          raise_resource_not_available_error! unless discussion&.can_resolve?(current_user)
+        end
+      end
+
+      def find_object(id:)
+        GitlabSchema.object_from_id(id, expected_type: ::Discussion)
+      end
+
+      def resolve!(discussion)
+        ::Discussions::ResolveService.new(
+          discussion.project,
+          current_user,
+          one_or_more_discussions: discussion
+        ).execute
+      end
+
+      def unresolve!(discussion)
+        discussion.unresolve!
+      end
+    end
+  end
+end