Ticket #14766: meta_filters.patch

meta.php

@@ -45 +45 @@
         // expected_slashed ($meta_key)
         $meta_key = stripslashes($meta_key);
 
+        $check = apply_filters( "add_{$meta_type}_metadata" , false, $object_id, $meta_key, $meta_value, $unique );
+        if ( false !== $check )
+                return true;
+
         if ( $unique && $wpdb->get_var( $wpdb->prepare(
                 "SELECT COUNT(*) FROM $table WHERE meta_key = %s AND $column = %d",
                 $meta_key, $object_id ) ) )
@@ -106 +110 @@
         // expected_slashed ($meta_key)
         $meta_key = stripslashes($meta_key);
 
+        $check = apply_filters( "update_{$meta_type}_metadata" , false, $object_id, $meta_key, $meta_value, $prev_value );
+        if ( false !== $check )
+                return true;
+
         if ( ! $meta_id = $wpdb->get_var( $wpdb->prepare( "SELECT $id_column FROM $table WHERE meta_key = %s AND $column = %d", $meta_key, $object_id ) ) )
                 return add_metadata($meta_type, $object_id, $meta_key, $meta_value);
 
@@ -178 +186 @@
         $meta_key = stripslashes($meta_key);
         $meta_value = maybe_serialize( stripslashes_deep($meta_value) );
 
+        $check = apply_filters( "delete_{$meta_type}_metadata" , false, $object_id, $meta_key, $meta_value, $delete_all );
+        if ( false !== $check )
+                return true;
+
         $query = $wpdb->prepare( "SELECT $id_column FROM $table WHERE meta_key = %s", $meta_key );
 
         if ( !$delete_all )
@@ -227 +239 @@
         if ( !$object_id = absint($object_id) )
                 return false;
 
+        $check = apply_filters( "get_{$meta_type}_metadata" , false, $object_id, $meta_key, $single );
+        if ( false !== $check ) {
+                if ( !is_array( $check ) )
+                        return $check;
+                elseif ( $single )
+                        return maybe_unserialize( $check[0] );
+                else
+                        return array_map('maybe_unserialize', $check);
+        }
+
         $meta_cache = wp_cache_get($object_id, $meta_type . '_meta');
 
         if ( !$meta_cache ) {