[IGNITE-15396] TableManager#table(UUID) could return null value even though the required table is already created

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 3.0.0-alpha4
• Labels: ignite-3
• Assignee: Vladislav Pyatkov
• Reporter: Vyacheslav Koptilin
• Reviewer: Alexander Lapin
• Created: 30/Aug/21 19:16
• Updated: 13/Oct/21 18:48
• Resolved: 12/Oct/21 15:52

Description

It seems that the following code introduced by IGNITE-14970 can lead to an error if a required table already exists in the cluster but the current node has not seen this event:

if (tbl != null && getTblFut.complete(tbl) || getTblFut.complete(null))
    removeListener(TableEvent.CREATE, clo, null);

 

https://github.com/apache/ignite-3/blob/main/modules/table/src/main/java/org/apache/ignite/internal/table/distributed/TableManager.java#L832

Looks like it should be something as follows:

if (tbl != null && getTblFut.complete(tbl) || 
    !isTableConfigured(id) && getTblFut.complete(null))
    removeListener(TableEvent.CREATE, clo, null);

 UPD 1

 Besides mention above it's also required to check whether table is present in meta storage, instead of just checking it locally

As-Is:

var tbl = tablesById.get(id);

if (tbl != null)
    return tbl;

To-Be:

if (!tableIdsConfigured().values().contains(id))
    return null;
    
var tbl = tablesById.get(id);

if (tbl != null)
    return tbl;

However proper retrieval of distributed state is not implemented yet IGNITE-15412

There's a hack solution

    private Map</* table name*/String, /* table id*/IgniteUuid> tableCoordinatesConfigured() {
        IgniteBiTuple<ByteArray, ByteArray> range = toRange(new ByteArray(PUBLIC_PREFIX));        var tableCoordinates = new HashMap<String, IgniteUuid>();
        String tblName = null;
        String innerTblId = null;        try (Cursor<Entry> cursor = metaStorageMgr.range(range.get1(), range.get2())) {
            while (cursor.hasNext()) {
                Entry entry = cursor.next();                List<String> keySplit = ConfigurationUtil.split(entry.key().toString());                if (keySplit.size() == 5 && NamedListNode.NAME.equals(keySplit.get(4))) {
                    @Nullable byte[] value = entry.value();
                    if (value != null) {
                        tblName = ByteUtils.fromBytes(value).toString();
                        innerTblId = keySplit.get(3);
                    }
                }                if (keySplit.size() == 5 && "id".equals(keySplit.get(4)) && keySplit.get(3).equals(innerTblId))
                    tableCoordinates.put(tblName, IgniteUuid.fromString(ByteUtils.fromBytes(entry.value()).toString()));
            }
        }
        catch (Exception e) {
            LOG.error("Can't get table names.", e);
        }        return tableCoordinates;
    }

However it's extremely horrible, so we'd better wait for IGNITE-15412

 

Issue Links

• is blocked by: IGNITE-15412 Configuration registry: add ability to retreive distributed value
• links to: GitHub Pull Request #388