[Backport] [3.x] Detect Apache5HttpClient in AWS SDK transport body-method guardrail (#1970)

CHANGELOG.md

@@ -3,6 +3,7 @@ Inspired from [Keep a Changelog](https://keepachangelog.com/en/1.0.0/)
 
 ## [Unreleased 3.x]
 ### Added
+- Detect AWS SDK `Apache5HttpClient` in `AwsSdk2Transport` body-method guardrail ([#1903](https://github.com/opensearch-project/opensearch-java/pull/1970))
 
 ### Dependencies
 

java-client/build.gradle.kts

@@ -228,6 +228,7 @@ dependencies {
     testImplementation("software.amazon.awssdk", "http-auth-aws", "[2.21,3.0)")
     testImplementation("software.amazon.awssdk", "aws-crt-client", "[2.21,3.0)")
     testImplementation("software.amazon.awssdk", "apache-client", "[2.21,3.0)")
+    testImplementation("software.amazon.awssdk", "apache5-client", "[2.34,3.0)")
     testImplementation("software.amazon.awssdk", "netty-nio-client", "[2.21,3.0)")
     testImplementation("software.amazon.awssdk", "url-connection-client", "[2.21,3.0)")
     testImplementation("software.amazon.awssdk", "sts", "[2.21,3.0)")

java-client/src/main/java/org/opensearch/client/transport/aws/AwsSdk2Transport.java

@@ -22,10 +22,14 @@
 import java.net.URLEncoder;
 import java.time.Clock;
 import java.util.AbstractMap;
+import java.util.Arrays;
 import java.util.Collection;
+import java.util.Collections;
+import java.util.HashSet;
 import java.util.Map;
 import java.util.Objects;
 import java.util.Optional;
+import java.util.Set;
 import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.ExecutionException;
 import java.util.function.Function;
@@ -85,6 +89,23 @@ public class AwsSdk2Transport implements OpenSearchTransport {
     public static final Integer DEFAULT_REQUEST_COMPRESSION_SIZE = 8192;
 
     private static final byte[] NO_BYTES = new byte[0];
+
+    /**
+     * FQCNs of Apache-backed AWS SDK HTTP clients (v4, v5) that share the body-on-GET/DELETE limitation.
+     */
+    private static final Set<String> APACHE_HTTP_CLIENT_CLASS_NAMES = Collections.unmodifiableSet(
+        new HashSet<>(
+            Arrays.asList("software.amazon.awssdk.http.apache.ApacheHttpClient", "software.amazon.awssdk.http.apache5.Apache5HttpClient")
+        )
+    );
+
+    /**
+     * Package-private to allow assertions in unit tests.
+     */
+    static boolean isAwsSdkApacheHttpClient(SdkAutoCloseable httpClient) {
+        return httpClient instanceof SdkHttpClient && APACHE_HTTP_CLIENT_CLASS_NAMES.contains(httpClient.getClass().getName());
+    }
+
     private final SdkAutoCloseable httpClient;
     private final boolean isApacheHttpClient;
     private final String host;
@@ -196,8 +217,7 @@ private AwsSdk2Transport(
     ) {
         Objects.requireNonNull(host, "Target OpenSearch service host must not be null");
         this.httpClient = httpClient;
-        this.isApacheHttpClient = httpClient instanceof SdkHttpClient
-            && httpClient.getClass().getName().equals("software.amazon.awssdk.http.apache.ApacheHttpClient");
+        this.isApacheHttpClient = isAwsSdkApacheHttpClient(httpClient);
         this.host = host;
         this.signingServiceName = signingServiceName;
         this.signingRegion = signingRegion;

java-client/src/test/java/org/opensearch/client/transport/aws/AwsSdk2TransportApacheDetectionTests.java

@@ -0,0 +1,54 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+
+package org.opensearch.client.transport.aws;
+
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+
+import org.junit.Test;
+import software.amazon.awssdk.http.SdkHttpClient;
+import software.amazon.awssdk.http.apache.ApacheHttpClient;
+import software.amazon.awssdk.http.apache5.Apache5HttpClient;
+import software.amazon.awssdk.http.urlconnection.UrlConnectionHttpClient;
+import software.amazon.awssdk.utils.SdkAutoCloseable;
+
+public class AwsSdk2TransportApacheDetectionTests {
+
+    @Test
+    public void nullReturnsFalse() {
+        assertFalse(AwsSdk2Transport.isAwsSdkApacheHttpClient(null));
+    }
+
+    @Test
+    public void urlConnectionReturnsFalse() {
+        try (SdkHttpClient client = UrlConnectionHttpClient.builder().build()) {
+            assertFalse(AwsSdk2Transport.isAwsSdkApacheHttpClient(client));
+        }
+    }
+
+    @Test
+    public void apacheV4ReturnsTrue() {
+        try (SdkHttpClient client = ApacheHttpClient.builder().build()) {
+            assertTrue(AwsSdk2Transport.isAwsSdkApacheHttpClient(client));
+        }
+    }
+
+    @Test
+    public void apacheV5ReturnsTrue() {
+        try (SdkHttpClient client = Apache5HttpClient.builder().build()) {
+            assertTrue(AwsSdk2Transport.isAwsSdkApacheHttpClient(client));
+        }
+    }
+
+    @Test
+    public void nonHttpClientWithMatchingNameReturnsFalse() {
+        SdkAutoCloseable notAnHttpClient = () -> {};
+        assertFalse(AwsSdk2Transport.isAwsSdkApacheHttpClient(notAnHttpClient));
+    }
+}