Multisite: Better invalidation

See: #37

include/invalidate.php

@@ -98,6 +98,13 @@
  expire( sprintf( 'post:%d:%d', $blog_id, $post_id ) );
 }, 10, 2 );
 
+// Multisite network/blog flags.
+add_action( 'init', function() {
+ if ( is_multisite() ) {
+ flag( sprintf( 'network:%d:%d', get_current_network_id(), get_current_blog_id() ) );
+ }
+} );
+
 // Last-minute expirations, save flags.
 add_action( 'shutdown', function() {
  $flush_actions = [
@@ -117,13 +124,28 @@
  'update_option_page_for_posts',
  'update_option_posts_per_page',
  'update_option_woocommerce_permalinks',
- 'automatic_updates_complete',
- '_core_updated_successfully',
  ];
 
  $flush_actions = apply_filters( 'surge_flush_actions', $flush_actions );
 
+ $ms_flush_actions = [
+ '_core_updated_successfully',
+ 'automatic_updates_complete',
+ ];
+
+ $expire_flag = is_multisite()
+ ? sprintf( 'network:%d:%d', get_current_network_id(), get_current_blog_id() )
+ : '/';
+
  foreach ( $flush_actions as $action ) {
+ if ( did_action( $action ) ) {
+ expire( $expire_flag );
+ break;
+ }
+ }
+
+ // Multisite flush actions expire the entire network.
+ foreach ( $ms_flush_actions as $action ) {
  if ( did_action( $action ) ) {
  expire( '/' );
  break;