PR cleanups

Author: alextwoods

services/s3/src/main/java/software/amazon/awssdk/services/s3/internal/crt/CrtResponseFileResponseTransformer.java

@@ -27,6 +27,8 @@
 
 /**
  * When the CRT Response File option is used in a request, the body is streamed directly to the file.
+ * The S3CrtResponseHandlerAdapter in this case will never receive a response body but will call onStream
+ * when the request is complete with a publisher that will complete immediately.
  * This transformer is effectively a no-op transformer that waits for the stream to complete and then
  * completes the future with the response.
  *
@@ -62,7 +64,7 @@ public void exceptionOccurred(Throwable throwable) {
         if (cf != null) {
             cf.completeExceptionally(throwable);
         } else {
-            log.warn(() -> "An exception occurred before the call to prepare() was able to instantiate the CompletableFuture."
+            log.warn(() -> "An exception occurred before the call to prepare() was able to instantiate the CompletableFuture. "
                            + "The future cannot be completed exceptionally because it is null");
         }
     }
@@ -85,12 +87,14 @@ public void onSubscribe(Subscription s) {
                 return;
             }
             this.subscription = s;
-            // Request the first chunk to start producing content
-            s.request(1);
+            // do not request data from the subscription since body is written directly to file
         }
 
         @Override
         public void onNext(ByteBuffer byteBuffer) {
+            // The response body is streamed directly to the file - this method should never be called.
+            // ensure the future is completed exceptionally if this occurs
+            onErrorMethod.accept(new IllegalStateException("OnCompleteSubscriber received unexpected call to onNext."));
         }
 
         @Override

services/s3/src/test/java/software/amazon/awssdk/services/s3/internal/crt/CrtResponseFileResponseTransformerTest.java

@@ -24,20 +24,21 @@
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 import org.mockito.Mockito;
+import org.reactivestreams.Subscriber;
 import software.amazon.awssdk.core.SdkResponse;
 import software.amazon.awssdk.core.async.AsyncRequestBody;
 import software.amazon.awssdk.core.async.SdkPublisher;
 
 public class CrtResponseFileResponseTransformerTest {
     private CrtResponseFileResponseTransformer<SdkResponse> transformer;
     private SdkResponse response;
-    private SdkPublisher<ByteBuffer> publisher;
+    private MockCrtPublisher publisher;
 
     @BeforeEach
     public void setUp() throws Exception {
         transformer = new CrtResponseFileResponseTransformer<>();
         response = Mockito.mock(SdkResponse.class);
-        publisher = AsyncRequestBody.fromString("");
+        publisher = new MockCrtPublisher();
     }
 
     @Test
@@ -46,6 +47,7 @@ void successfulResponseAndStream_returnsResponsePublisher() throws Exception {
         transformer.onResponse(response);
         assertThat(responseFuture.isDone()).isFalse();
         transformer.onStream(publisher);
+        publisher.complete();
         assertThat(responseFuture.isDone()).isTrue();
         SdkResponse returnedResponse = responseFuture.get();
         assertThat(returnedResponse).isEqualTo(response);
@@ -74,4 +76,16 @@ void failedStream_completesExceptionally() {
             .hasCauseInstanceOf(RuntimeException.class);
     }
 
+    private static class MockCrtPublisher implements SdkPublisher<ByteBuffer> {
+        private Subscriber<? super ByteBuffer> subscriber;
+        @Override
+        public void subscribe(Subscriber<? super ByteBuffer> s) {
+            subscriber = s;
+        }
+
+        public void complete() {
+            subscriber.onComplete();
+        }
+    }
+
 }

services/s3/src/test/java/software/amazon/awssdk/services/s3/internal/crt/S3CrtAsyncHttpClientTest.java

@@ -571,16 +571,14 @@ public void responseFilePathAndOption_shouldPassToCrt() {
         Path path = RandomTempFile.randomUncreatedFile().toPath();
 
         AsyncExecuteRequest asyncExecuteRequest = getExecuteRequestBuilder()
-            .putHttpExecutionAttribute(OPERATION_NAME,"GetObject")
+            .putHttpExecutionAttribute(OPERATION_NAME, "GetObject")
             .putHttpExecutionAttribute(RESPONSE_FILE_PATH, path)
             .putHttpExecutionAttribute(RESPONSE_FILE_OPTION, S3MetaRequestOptions.ResponseFileOption.CREATE_OR_APPEND)
             .build();
 
         S3MetaRequestOptions actual = makeRequest(asyncExecuteRequest);
         assertThat(actual.getResponseFilePath()).isEqualTo(path);
         assertThat(actual.getResponseFileOption()).isEqualTo(S3MetaRequestOptions.ResponseFileOption.CREATE_OR_APPEND);
-        S3MetaRequestResponseHandler handler = actual.getResponseHandler();
-        System.out.println(handler);
     }
 
     private AsyncExecuteRequest.Builder getExecuteRequestBuilder() {