[jira] [Resolved] (HADOOP-16433) S3Guard: Filter expired entries and tombstones when listing with MetadataStore#listChildren

["Steve Loughran (JIRA)" <ji...@apache.org>]

     [ https://issues.apache.org/jira/browse/HADOOP-16433?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Steve Loughran resolved HADOOP-16433.
-------------------------------------
    Resolution: Fixed

+1, committed to trunk.

Thanks!

> S3Guard: Filter expired entries and tombstones when listing with MetadataStore#listChildren
> -------------------------------------------------------------------------------------------
>
>                 Key: HADOOP-16433
>                 URL: https://issues.apache.org/jira/browse/HADOOP-16433
>             Project: Hadoop Common
>          Issue Type: Sub-task
>          Components: fs/s3
>    Affects Versions: 3.3.0
>            Reporter: Gabor Bota
>            Assignee: Gabor Bota
>            Priority: Blocker
>
> Currently, we don't filter out entries in {{listChildren}} implementations.
> This can cause bugs and inconsistencies, so this should be fixed.
> It can lead to a status where we can't recover from the following:
> {{guarded and raw (OOB op) clients are doing ops to S3}}
> {noformat}
> Guarded: touch /AAAA
> Guarded: touch /ZZZZ
> Guarded: rm /AAAA {{-> tombstone in MS}}
> RAW: touch /AAAA/file.ext {{-> file is hidden with a tombstone}}
> Guarded: ls / {{-> only ZZZZ will show up in the listing. }}
> {noformat}
> After we change the following code
> {code:java}
>           final List<PathMetadata> metas = new ArrayList<>();
>           for (Item item : items) {
>             DDBPathMetadata meta = itemToPathMetadata(item, username);
>             metas.add(meta);
>           }
> {code}
> to 
> {code:java}
>             // handle expiry - only add not expired entries to listing.
>             if (meta.getLastUpdated() == 0 ||
>                 !meta.isExpired(ttlTimeProvider.getMetadataTtl(),
>                 ttlTimeProvider.getNow())) {
>               metas.add(meta);
>             }
> {code}
> we will filter out expired entries from the listing, so we can recover form these kind of OOB ops.
> Note:  we have to handle the lastUpdated == 0 case, where the lastUpdated field is not filled in!
> Note: this can only be fixed cleanly after HADOOP-16383 is fixed because we need to have the TTLtimeProvider in MS to handle this internally.



--
This message was sent by Atlassian JIRA
(v7.6.14#76016)

---------------------------------------------------------------------
To unsubscribe, e-mail: common-dev-unsubscribe@hadoop.apache.org
For additional commands, e-mail: common-dev-help@hadoop.apache.org