Lokesh Khurana created PHOENIX-7965:
---------------------------------------
Summary: ConnectionQueryServicesImpl.getMetaDataCache() returns
null after connection close, causing a bare NPE during concurrent query
compilation
Key: PHOENIX-7965
URL: https://issues.apache.org/jira/browse/PHOENIX-7965
Project: Phoenix
Issue Type: Bug
Reporter: Lokesh Khurana
Assignee: Lokesh Khurana
Problem
ConnectionQueryServicesImpl.getMetaDataCache() is unguarded:
public PMetaData getMetaDataCache() {
return latestMetaData; // no null check
}
ConnectionQueryServicesImpl.close() sets latestMetaData = null (the field is
private volatile PMetaData latestMetaData). The JDBC compile path reads the
shared cache via
PhoenixConnection.getTableRef() →
getQueryServices().getMetaDataCache().getTableRef(key). If a connection/CQSI is
closed concurrently with an in-flight query compilation (e.g. during a
cluster failover or connection-pool teardown), getMetaDataCache() returns
null and the subsequent .getTableRef(key) throws a bare, causeless
NullPointerException with no message — opaque to
operators and hard to triage. The same exposure exists via
PhoenixConnection.getFunction() and getSchema().
Root cause
Introduced by PHOENIX-6761 ("Phoenix Client Side Metadata Caching
Improvement", commit 9f31c3eca3), which replaced PhoenixConnection's
per-connection metadata snapshot with a read of the
shared, close()-nullable CQSI cache and added the unguarded
getMetaDataCache() accessor. A guard method,
throwConnectionClosedIfNullMetaData(), already exists and is invoked by every
other
cache accessor/mutator (addTable, removeTable, pruneTables, the internal
getTable, etc.) — but not by getMetaDataCache(), which is the one accessor the
compile path uses.
Fix
Invoke throwConnectionClosedIfNullMetaData() inside getMetaDataCache() so a
closed connection surfaces the existing descriptive "Connection to the cluster
is closed" exception instead of a
bare NPE. This makes the failure diagnosable and consistent with the other
accessors. Add a unit test asserting the descriptive exception (not a bare NPE)
when the cache has been nulled by
close().
--
This message was sent by Atlassian Jira
(v8.20.10#820010)
