Fix NullPointerException when publishing an SNS batch without a topic ARN

Author: anjeongkyun

dd-java-agent/instrumentation/aws-java/aws-java-sns-1.0/src/main/java/datadog/trace/instrumentation/aws/v1/sns/SnsInterceptor.java

@@ -90,6 +90,9 @@ public AmazonWebServiceRequest beforeMarshalling(AmazonWebServiceRequest request
       PublishBatchRequest pmbRequest = (PublishBatchRequest) request;
       // Extract the topic name from the ARN for DSM
       String topicName = pmbRequest.getTopicArn();
+      if (null == topicName) {
+        return request; // no topic to attribute the batch to, leave it untouched
+      }
       topicName = topicName.substring(topicName.lastIndexOf(':') + 1);
 
       final ByteBuffer bytebuffer = this.getMessageAttributeValueToInject(request, topicName);

dd-java-agent/instrumentation/aws-java/aws-java-sns-1.0/src/test/groovy/SnsClientTest.groovy

@@ -1,9 +1,12 @@
+import com.amazonaws.AmazonClientException
 import com.amazonaws.auth.AWSStaticCredentialsProvider
 import com.amazonaws.auth.BasicAWSCredentials
 import com.amazonaws.client.builder.AwsClientBuilder
 import com.amazonaws.services.sns.AmazonSNSClient
 import com.amazonaws.services.sns.AmazonSNSClientBuilder
 import com.amazonaws.services.sns.model.MessageAttributeValue
+import com.amazonaws.services.sns.model.PublishBatchRequest
+import com.amazonaws.services.sns.model.PublishBatchRequestEntry
 import com.amazonaws.services.sns.model.PublishRequest
 import datadog.trace.agent.test.naming.VersionedNamingTestBase
 import datadog.trace.agent.test.utils.TraceUtils
@@ -235,6 +238,15 @@ abstract class SnsClientTest extends VersionedNamingTestBase {
     then:
     noExceptionThrown()
   }
+
+  def "SNS batch without topic ARN doesn't leak exception"() {
+    when:
+    snsClient.publishBatch(new PublishBatchRequest()
+      .withPublishBatchRequestEntries(new PublishBatchRequestEntry().withId("1").withMessage('sometext')))
+
+    then:
+    thrown(AmazonClientException)
+  }
 }
 
 class SnsClientV0Test extends SnsClientTest {

dd-java-agent/instrumentation/aws-java/aws-java-sns-2.0/src/main/java/datadog/trace/instrumentation/aws/v2/sns/SnsInterceptor.java

@@ -81,6 +81,9 @@ public SdkRequest modifyRequest(ModifyRequest context, ExecutionAttributes execu
       PublishBatchRequest request = (PublishBatchRequest) context.request();
       // Get topic name for DSM
       String snsTopicArn = request.topicArn();
+      if (null == snsTopicArn) {
+        return request; // no topic to attribute the batch to, leave it untouched
+      }
       String snsTopicName = snsTopicArn.substring(snsTopicArn.lastIndexOf(':') + 1);
       ArrayList<PublishBatchRequestEntry> entries = new ArrayList<>();
       SdkBytes value = this.getMessageAttributeValueToInject(executionAttributes, snsTopicName);

dd-java-agent/instrumentation/aws-java/aws-java-sns-2.0/src/test/groovy/SnsClientTest.groovy

@@ -13,6 +13,8 @@ import software.amazon.awssdk.auth.credentials.AwsBasicCredentials
 import software.amazon.awssdk.auth.credentials.StaticCredentialsProvider
 import software.amazon.awssdk.regions.Region
 import software.amazon.awssdk.services.sns.SnsClient
+import software.amazon.awssdk.core.exception.SdkException
+import software.amazon.awssdk.services.sns.model.PublishBatchRequestEntry
 import software.amazon.awssdk.services.sns.model.PublishResponse
 import software.amazon.awssdk.services.sqs.SqsClient
 import software.amazon.awssdk.services.sqs.model.QueueAttributeName
@@ -184,6 +186,16 @@ abstract class SnsClientTest extends VersionedNamingTestBase {
     noExceptionThrown()
   }
 
+  def "SNS batch without topic ARN doesn't leak exception"() {
+    when:
+    snsClient.publishBatch {
+      it.publishBatchRequestEntries(PublishBatchRequestEntry.builder().id("1").message("sometext").build())
+    }
+
+    then:
+    thrown(SdkException)
+  }
+
   def "test propagation styles"() {
     when:
     TEST_WRITER.clear()