Optimize user_get_all_accessible_projects()

dregad · dregad · commit cc7703acc8d0 · 2013-05-01T16:54:39.000+02:00
On instances having a large number of projects, this function would
consume significant resources while processing all the subprojects to
determine if one is accessible to the user (about 25 seconds to load
main_page.php for 5'000 projects, without subprojects).

The performance bottleneck was the array_merge() call in the loop. This
has been replaced by a foreach working on an associative array. The same
page now loads under 1 second.

Fixes #9876
diff --git a/core/user_api.php b/core/user_api.php
@@ -1008,12 +1008,18 @@ function user_get_all_accessible_subprojects( $p_user_id, $p_project_id ) {
 
 function user_get_all_accessible_projects( $p_user_id, $p_project_id ) {
 	if( ALL_PROJECTS == $p_project_id ) {
-		$t_topprojects = $t_project_ids = user_get_accessible_projects( $p_user_id );
+		$t_topprojects = user_get_accessible_projects( $p_user_id );
+
+		# Create a combined array where key = value
+		$t_project_ids = array_combine( $t_topprojects, $t_topprojects );
+
+		# Add all subprojects user has access to
 		foreach( $t_topprojects as $t_project ) {
-			$t_project_ids = array_merge( $t_project_ids, user_get_all_accessible_subprojects( $p_user_id, $t_project ) );
+			$t_subprojects_ids = user_get_all_accessible_subprojects( $p_user_id, $t_project );
+			foreach( $t_subprojects_ids as $t_id ) {
+				$t_project_ids[$t_id] = $t_id;
+			}
 		}
-
-		$t_project_ids = array_unique( $t_project_ids );
 	} else {
 		access_ensure_project_level( VIEWER, $p_project_id );
 		$t_project_ids = user_get_all_accessible_subprojects( $p_user_id, $p_project_id );
