[Logging] added trace logging to TransportShardSingleOperationAction

And enabled them on SimpleRecoveryTests.testSimpleRecovery

src/main/java/org/elasticsearch/action/get/GetRequest.java

@@ -305,6 +305,6 @@ public class GetRequest extends SingleShardOperationRequest<GetRequest> {
 
     @Override
     public String toString() {
-        return "[" + index + "][" + type + "][" + id + "]: routing [" + routing + "]";
+        return "get [" + index + "][" + type + "][" + id + "]: routing [" + routing + "]";
     }
 }

src/main/java/org/elasticsearch/action/support/single/shard/TransportShardSingleOperationAction.java

@@ -107,6 +107,9 @@ public abstract class TransportShardSingleOperationAction<Request extends Single
             this.listener = listener;
 
             ClusterState clusterState = clusterService.state();
+            if (logger.isTraceEnabled()) {
+                logger.trace("executing [{}] based on cluster state version [{}]", request, clusterState.version());
+            }
             nodes = clusterState.nodes();
             ClusterBlockException blockException = checkGlobalBlock(clusterState, request);
             if (blockException != null) {
@@ -151,8 +154,10 @@ public abstract class TransportShardSingleOperationAction<Request extends Single
                 listener.onFailure(failure);
                 return;
             }
-
             if (shardRouting.currentNodeId().equals(nodes.localNodeId())) {
+                if (logger.isTraceEnabled()) {
+                    logger.trace("executing [{}] on shard [{}]", request, shardRouting.shardId());
+                }
                 try {
                     if (request.operationThreaded()) {
                         request.beforeLocalFork();
@@ -260,6 +265,9 @@ public abstract class TransportShardSingleOperationAction<Request extends Single
 
         @Override
         public void messageReceived(final ShardSingleOperationRequest request, final TransportChannel channel) throws Exception {
+            if (logger.isTraceEnabled()) {
+                logger.trace("executing [{}] on shard [{}]", request.request(), request.shardId());
+            }
             Response response = shardOperation(request.request(), request.shardId());
             channel.sendResponse(response);
         }

src/test/java/org/elasticsearch/recovery/SimpleRecoveryTests.java

@@ -25,6 +25,7 @@ import org.elasticsearch.action.get.GetResponse;
 import org.elasticsearch.common.settings.ImmutableSettings;
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.test.ElasticsearchIntegrationTest;
+import org.elasticsearch.test.junit.annotations.TestLogging;
 import org.junit.Test;
 
 import static org.elasticsearch.client.Requests.*;
@@ -49,6 +50,7 @@ public class SimpleRecoveryTests extends ElasticsearchIntegrationTest {
     }
 
     @Test
+    @TestLogging(value = "cluster.service:TRACE,action.get:TRACE")
     public void testSimpleRecovery() throws Exception {
         assertAcked(prepareCreate("test", 1).execute().actionGet(5000));