You are viewing a plain text version of this content. The canonical link for it is here.
Posted to dev@curator.apache.org by "Cameron McKenzie (JIRA)" <ji...@apache.org> on 2018/08/14 00:17:00 UTC
[jira] [Resolved] (CURATOR-476) PathChildrenCache never gets
initialized if a child dies even before a data watch is registered for it
[ https://issues.apache.org/jira/browse/CURATOR-476?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Cameron McKenzie resolved CURATOR-476.
--------------------------------------
Resolution: Fixed
Fix Version/s: 4.1.0
> PathChildrenCache never gets initialized if a child dies even before a data watch is registered for it
> ------------------------------------------------------------------------------------------------------
>
> Key: CURATOR-476
> URL: https://issues.apache.org/jira/browse/CURATOR-476
> Project: Apache Curator
> Issue Type: Bug
> Components: Recipes
> Reporter: Rohan Suri
> Priority: Major
> Fix For: 4.1.0
>
>
> h5. What's happening:
> When PathChildrenCache is started with PathChildrenCache.StartMode.POST_INITIALIZED_EVENT there could be the following scenario:
> 1. PCC calls getChildren("../parent") and gets the list of it's children
> 2. PCC calls processChildren(...) where it puts them into it's \{initialSet} – set of children whose data it will fetch and cache
> 3. Later in the same method it calls getDataAndStat(..."/parent/somechild") where it calls getData(...) on this child and registers a dataWatcher for this child
> Midst of step 2&3, child node could get deleted – but since step 3 hasn't completed yet, the dataWatcher isn't triggered (since it is not even registered) and we miss the NodeDeleted event.
> Since our \{initialSet} still contains the child path, the initialized event is never fired.
> h5. The fix:
> As of now there's only one codepath to removing a path from the \{initialSet} (done from the data watcher)
> The remove should also be called in the callback of our getData(..."/parent/somechild") being done in Step 3 if the resultCode=-101(KeeperException.NoNode)
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)