[7.17] More verbose logging in IndicesSegmentsRestCancellationIT (#113844) (#120025)

* More verbose logging in `IndicesSegmentsRestCancellationIT` (#113844)

Relates #88201

(cherry picked from commit cd42719)

* Fix logger reference

* Use String instead of Strings

---------

Co-authored-by: David Turner <[email protected]>

Author: ywangd

qa/smoke-test-http/src/javaRestTest/java/org/elasticsearch/http/BlockedSearcherRestCancellationTestCase.java

@@ -8,6 +8,9 @@
 
 package org.elasticsearch.http;
 
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+import org.elasticsearch.ElasticsearchException;
 import org.elasticsearch.action.support.PlainActionFuture;
 import org.elasticsearch.client.Cancellable;
 import org.elasticsearch.client.Request;
@@ -34,6 +37,7 @@
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.List;
+import java.util.Locale;
 import java.util.Optional;
 import java.util.concurrent.CancellationException;
 import java.util.concurrent.Semaphore;
@@ -134,6 +138,12 @@ public List<Setting<?>> getSettings() {
 
     private static class SearcherBlockingEngine extends ReadOnlyEngine {
 
+        // using a specialized logger for this case because and "logger" means "Engine#logger"
+        // (relates investigation into https://github.com/elastic/elasticsearch/issues/88201)
+        private static final Logger blockedSearcherRestCancellationTestCaseLogger = LogManager.getLogger(
+            BlockedSearcherRestCancellationTestCase.class
+        );
+
         final Semaphore searcherBlock = new Semaphore(1);
 
         SearcherBlockingEngine(EngineConfig config) {
@@ -142,12 +152,38 @@ private static class SearcherBlockingEngine extends ReadOnlyEngine {
 
         @Override
         public Searcher acquireSearcher(String source, SearcherScope scope, Function<Searcher, Searcher> wrapper) throws EngineException {
+            if (blockedSearcherRestCancellationTestCaseLogger.isDebugEnabled()) {
+                blockedSearcherRestCancellationTestCaseLogger.debug(
+                    String.format(
+                        Locale.ROOT,
+                        "in acquireSearcher for shard [%s] on thread [%s], availablePermits=%d",
+                        config().getShardId(),
+                        Thread.currentThread().getName(),
+                        searcherBlock.availablePermits()
+                    ),
+                    new ElasticsearchException("stack trace")
+                );
+            }
+
             try {
                 searcherBlock.acquire();
             } catch (InterruptedException e) {
                 throw new AssertionError(e);
             }
             searcherBlock.release();
+
+            if (blockedSearcherRestCancellationTestCaseLogger.isDebugEnabled()) {
+                blockedSearcherRestCancellationTestCaseLogger.debug(
+                    String.format(
+                        Locale.ROOT,
+                        "continuing in acquireSearcher for shard [%s] on thread [%s], availablePermits=%d",
+                        config().getShardId(),
+                        Thread.currentThread().getName(),
+                        searcherBlock.availablePermits()
+                    )
+                );
+            }
+
             return super.acquireSearcher(source, scope, wrapper);
         }
     }

qa/smoke-test-http/src/javaRestTest/java/org/elasticsearch/http/IndicesSegmentsRestCancellationIT.java

@@ -11,12 +11,23 @@
 import org.apache.http.client.methods.HttpGet;
 import org.elasticsearch.action.admin.indices.segments.IndicesSegmentsAction;
 import org.elasticsearch.client.Request;
+import org.elasticsearch.test.junit.annotations.TestIssueLogging;
 
 public class IndicesSegmentsRestCancellationIT extends BlockedSearcherRestCancellationTestCase {
+    @TestIssueLogging(
+        issueUrl = "https://github.com/elastic/elasticsearch/issues/88201",
+        value = "org.elasticsearch.http.BlockedSearcherRestCancellationTestCase:DEBUG"
+            + ",org.elasticsearch.transport.TransportService:TRACE"
+    )
     public void testIndicesSegmentsRestCancellation() throws Exception {
         runTest(new Request(HttpGet.METHOD_NAME, "/_segments"), IndicesSegmentsAction.NAME);
     }
 
+    @TestIssueLogging(
+        issueUrl = "https://github.com/elastic/elasticsearch/issues/88201",
+        value = "org.elasticsearch.http.BlockedSearcherRestCancellationTestCase:DEBUG"
+            + ",org.elasticsearch.transport.TransportService:TRACE"
+    )
     public void testCatSegmentsRestCancellation() throws Exception {
         runTest(new Request(HttpGet.METHOD_NAME, "/_cat/segments"), IndicesSegmentsAction.NAME);
     }