CCE when re-throwing "shard not available" exception in TransportShardMultiGetAction

[itsnotv]

ClassCastException can be thrown by callers of TransportActions.isShardNotAvailableException(e) as e is not always an instance of ElasticSearchException

fixes #32173

[elasticmachine]

Pinging @elastic/es-distributed

[bleskes]

Thanks @itsnotv . How about doing it like this:

Index: server/src/main/java/org/elasticsearch/action/get/TransportShardMultiGetAction.java
<+>UTF-8
===================================================================
--- server/src/main/java/org/elasticsearch/action/get/TransportShardMultiGetAction.java	(date 1531906244000)
+++ server/src/main/java/org/elasticsearch/action/get/TransportShardMultiGetAction.java	(date 1531986507000)
@@ -20,7 +20,6 @@
 package org.elasticsearch.action.get;
 
 import org.apache.logging.log4j.message.ParameterizedMessage;
-import org.elasticsearch.ElasticsearchException;
 import org.elasticsearch.action.support.ActionFilters;
 import org.elasticsearch.action.support.TransportActions;
 import org.elasticsearch.action.support.single.shard.TransportSingleShardAction;
@@ -90,9 +89,9 @@
                 GetResult getResult = indexShard.getService().get(item.type(), item.id(), item.storedFields(), request.realtime(), item.version(),
                     item.versionType(), item.fetchSourceContext());
                 response.add(request.locations.get(i), new GetResponse(getResult));
-            } catch (Exception e) {
+            } catch (RuntimeException e) {
                 if (TransportActions.isShardNotAvailableException(e)) {
-                    throw (ElasticsearchException) e;
+                    throw e;
                 } else {
                     logger.debug(() -> new ParameterizedMessage("{} failed to execute multi_get for [{}]/[{}]", shardId,
                         item.type(), item.id()), e);

Also note that there are other places in the code that do this (see last comment on #32173 ).

Last - do you mind adapting the issue description to be more complete?

Thanks again for working on this.

[itsnotv]

@bleskes updated the PR.

[bleskes]

@elasticmachine test this please

[dnhatn]

[ant:checkstyle] Running Checkstyle 8.10.1 on 2864 files
[ant:checkstyle] [ERROR] /var/lib/jenkins/workspace/elastic+elasticsearch+pull-request/server/src/main/java/org/elasticsearch/action/get/TransportShardMultiGetAction.java:23:8: Unused import - org.elasticsearch.ElasticsearchException. [UnusedImports]
[ant:checkstyle] [ERROR] /var/lib/jenkins/workspace/elastic+elasticsearch+pull-request/server/src/main/java/org/elasticsearch/action/termvectors/TransportShardMultiTermsVectorAction.java:23:8: Unused import - org.elasticsearch.ElasticsearchException. [UnusedImports]

@itsnotv Can you please remove unused imports in TransportShardMultiGetAction.java and TransportShardMultiTermsVectorAction.java? It would be great if you run ./gradlew precommit before pushing :).

[itsnotv]

@dnhatn done.

$ gradle precommit
BUILD SUCCESSFUL in 1h 6m 58s
2053 actionable tasks: 2053 executed

[dnhatn]

Thanks @itsnotv.

@elasticmachine test this please.

[bleskes]

LGTM. Thx @itsnotv