Add "unsafe" AsyncRequestBody constructors for byte[] and ByteBuffers

Author: StephenFlavin

.changes/next-release/feature-AWSSDKforJavav2-5d806ad.json

@@ -0,0 +1,6 @@
+{
+    "type": "feature",
+    "category": "AWS SDK for Java v2",
+    "contributor": "StephenFlavin",
+    "description": "Add \"unsafe\" AsyncRequestBody constructors for byte arrays and ByteBuffers"
+}

core/sdk-core/src/main/java/software/amazon/awssdk/core/async/AsyncRequestBody.java

@@ -22,37 +22,38 @@
 import java.nio.charset.Charset;
 import java.nio.charset.StandardCharsets;
 import java.nio.file.Path;
+import java.util.Arrays;
 import java.util.Optional;
 import java.util.concurrent.ExecutorService;
 import org.reactivestreams.Publisher;
 import org.reactivestreams.Subscriber;
 import software.amazon.awssdk.annotations.SdkPublicApi;
-import software.amazon.awssdk.core.internal.async.ByteArrayAsyncRequestBody;
+import software.amazon.awssdk.core.internal.async.ByteBuffersAsyncRequestBody;
 import software.amazon.awssdk.core.internal.async.FileAsyncRequestBody;
 import software.amazon.awssdk.core.internal.async.InputStreamWithExecutorAsyncRequestBody;
 import software.amazon.awssdk.core.internal.util.Mimetype;
 import software.amazon.awssdk.utils.BinaryUtils;
 
 /**
- * Interface to allow non-blocking streaming of request content. This follows the reactive streams pattern where
- * this interface is the {@link Publisher} of data (specifically {@link ByteBuffer} chunks) and the HTTP client is the Subscriber
- * of the data (i.e. to write that data on the wire).
+ * Interface to allow non-blocking streaming of request content. This follows the reactive streams pattern where this interface is
+ * the {@link Publisher} of data (specifically {@link ByteBuffer} chunks) and the HTTP client is the Subscriber of the data (i.e.
+ * to write that data on the wire).
  *
  * <p>
  * {@link #subscribe(Subscriber)} should be implemented to tie this publisher to a subscriber. Ideally each call to subscribe
- * should reproduce the content (i.e if you are reading from a file each subscribe call should produce a {@link
- * org.reactivestreams.Subscription} that reads the file fully). This allows for automatic retries to be performed in the SDK. If
- * the content is not reproducible,  an exception may be thrown from any subsequent {@link #subscribe(Subscriber)} calls.
+ * should reproduce the content (i.e if you are reading from a file each subscribe call should produce a
+ * {@link org.reactivestreams.Subscription} that reads the file fully). This allows for automatic retries to be performed in the
+ * SDK. If the content is not reproducible,  an exception may be thrown from any subsequent {@link #subscribe(Subscriber)} calls.
  * </p>
  *
  * <p>
- * It is important to only send the number of chunks that the subscriber requests to avoid out of memory situations.
- * The subscriber does it's own buffering so it's usually not needed to buffer in the publisher. Additional permits
- * for chunks will be notified via the {@link org.reactivestreams.Subscription#request(long)} method.
+ * It is important to only send the number of chunks that the subscriber requests to avoid out of memory situations. The
+ * subscriber does it's own buffering so it's usually not needed to buffer in the publisher. Additional permits for chunks will be
+ * notified via the {@link org.reactivestreams.Subscription#request(long)} method.
  * </p>
  *
  * @see FileAsyncRequestBody
- * @see ByteArrayAsyncRequestBody
+ * @see ByteBuffersAsyncRequestBody
  */
 @SdkPublicApi
 public interface AsyncRequestBody extends SdkPublisher<ByteBuffer> {
@@ -70,8 +71,8 @@ default String contentType() {
     }
 
     /**
-     * Creates an {@link AsyncRequestBody} the produces data from the input ByteBuffer publisher.
-     * The data is delivered when the publisher publishes the data.
+     * Creates an {@link AsyncRequestBody} the produces data from the input ByteBuffer publisher. The data is delivered when the
+     * publisher publishes the data.
      *
      * @param publisher Publisher of source data
      * @return Implementation of {@link AsyncRequestBody} that produces data send by the publisher
@@ -124,11 +125,11 @@ static AsyncRequestBody fromFile(File file) {
      * @param string The string to provide.
      * @param cs The {@link Charset} to use.
      * @return Implementation of {@link AsyncRequestBody} that uses the specified string.
-     * @see ByteArrayAsyncRequestBody
+     * @see ByteBuffersAsyncRequestBody
      */
     static AsyncRequestBody fromString(String string, Charset cs) {
-        return new ByteArrayAsyncRequestBody(string.getBytes(cs),
-                                             Mimetype.MIMETYPE_TEXT_PLAIN + "; charset=" + cs.name());
+        return ByteBuffersAsyncRequestBody.from(Mimetype.MIMETYPE_TEXT_PLAIN + "; charset=" + cs.name(),
+                                                string.getBytes(cs));
     }
 
     /**
@@ -143,29 +144,96 @@ static AsyncRequestBody fromString(String string) {
     }
 
     /**
-     * Creates a {@link AsyncRequestBody} from a byte array. The contents of the byte array are copied so modifications to the
-     * original byte array are not reflected in the {@link AsyncRequestBody}.
+     * Creates an {@link AsyncRequestBody} from a byte array. This will copy the contents of the byte array to prevent
+     * modifications to the provided byte array from being reflected in the {@link AsyncRequestBody}.
      *
      * @param bytes The bytes to send to the service.
      * @return AsyncRequestBody instance.
      */
     static AsyncRequestBody fromBytes(byte[] bytes) {
-        return new ByteArrayAsyncRequestBody(bytes, Mimetype.MIMETYPE_OCTET_STREAM);
+        byte[] clonedBytes = bytes.clone();
+        return ByteBuffersAsyncRequestBody.from(clonedBytes);
     }
 
     /**
-     * Creates a {@link AsyncRequestBody} from a {@link ByteBuffer}. Buffer contents are copied so any modifications
-     * made to the original {@link ByteBuffer} are not reflected in the {@link AsyncRequestBody}.
+     * Creates an {@link AsyncRequestBody} from a byte array <b>without</b> copying the contents of the byte array. This
+     * introduces concurrency risks, allowing: (1) the caller to modify the byte array stored in this {@code AsyncRequestBody}
+     * implementation AND (2) any users of {@link #fromBytesUnsafe(byte[])} to modify the byte array passed into this
+     * {@code AsyncRequestBody} implementation.
+     *
+     * <p>As the method name implies, this is unsafe. Use {@link #fromBytes(byte[])} unless you're sure you know the risks.
+     *
+     * @param bytes The bytes to send to the service.
+     * @return AsyncRequestBody instance.
+     */
+    static AsyncRequestBody fromBytesUnsafe(byte[] bytes) {
+        return ByteBuffersAsyncRequestBody.from(bytes);
+    }
+
+    /**
+     * Creates an {@link AsyncRequestBody} from a {@link ByteBuffer}. This will copy the contents of the {@link ByteBuffer} to
+     * prevent modifications to the provided {@link ByteBuffer} from being reflected in the {@link AsyncRequestBody}.
+     * <p> The position is set to 0 in the copied {@link ByteBuffer} and the mark if defined is discarded.
      *
      * @param byteBuffer ByteBuffer to send to the service.
      * @return AsyncRequestBody instance.
      */
     static AsyncRequestBody fromByteBuffer(ByteBuffer byteBuffer) {
-        return fromBytes(BinaryUtils.copyAllBytesFrom(byteBuffer));
+        ByteBuffer immutableCopy = BinaryUtils.immutableCopyOf(byteBuffer);
+        immutableCopy.rewind();
+        return ByteBuffersAsyncRequestBody.of(null, immutableCopy);
+    }
+
+    /**
+     * Creates an {@link AsyncRequestBody} from a {@link ByteBuffer} <b>without</b> copying the contents of the
+     * {@link ByteBuffer}. This introduces concurrency risks, allowing: (1) the caller to modify the {@link ByteBuffer} stored in
+     * this {@code AsyncRequestBody} implementation AND (2) any users of {@link #fromByteBufferUnsafe(ByteBuffer)} to modify the
+     * {@link ByteBuffer} passed into this {@code AsyncRequestBody} implementation.
+     *
+     * <p>As the method name implies, this is unsafe. Use {@link #fromByteBuffer(ByteBuffer)}} unless you're sure you know the
+     * risks.
+     *
+     * @param byteBuffer ByteBuffer to send to the service.
+     * @return AsyncRequestBody instance.
+     */
+    static AsyncRequestBody fromByteBufferUnsafe(ByteBuffer byteBuffer) {
+        return ByteBuffersAsyncRequestBody.of(null, byteBuffer);
+    }
+
+    /**
+     * Creates an {@link AsyncRequestBody} from a {@link ByteBuffer} array. This will copy the contents of each {@link ByteBuffer}
+     * to prevent modifications to any provided {@link ByteBuffer} from being reflected in the {@link AsyncRequestBody}.
+     * <p> The position is set to 0 in each copied {@link ByteBuffer} and the mark if defined is discarded.
+     *
+     * @param byteBuffers ByteBuffer array to send to the service.
+     * @return AsyncRequestBody instance.
+     */
+    static AsyncRequestBody fromByteBuffers(ByteBuffer... byteBuffers) {
+        ByteBuffer[] immutableCopy = Arrays.stream(byteBuffers)
+                                           .map(BinaryUtils::immutableCopyOf)
+                                           .peek(ByteBuffer::rewind)
+                                           .toArray(ByteBuffer[]::new);
+        return ByteBuffersAsyncRequestBody.of(null, immutableCopy);
+    }
+
+    /**
+     * Creates an {@link AsyncRequestBody} from a {@link ByteBuffer} array <b>without</b> copying the contents of each
+     * {@link ByteBuffer}. This introduces concurrency risks, allowing: (1) the caller to modify any {@link ByteBuffer} stored in
+     * this {@code AsyncRequestBody} implementation AND (2) any users of {@link #fromByteBufferUnsafe(ByteBuffer)} to modify any
+     * {@link ByteBuffer} passed into this {@code AsyncRequestBody} implementation.
+     *
+     * <p>As the method name implies, this is unsafe. Use {@link #fromByteBuffers(ByteBuffer...)} unless you're sure you know the
+     * risks.
+     *
+     * @param byteBuffers ByteBuffer array to send to the service.
+     * @return AsyncRequestBody instance.
+     */
+    static AsyncRequestBody fromByteBuffersUnsafe(ByteBuffer... byteBuffers) {
+        return ByteBuffersAsyncRequestBody.of(null, byteBuffers);
     }
 
     /**
-     * Creates a {@link AsyncRequestBody} from a {@link InputStream}.
+     * Creates an {@link AsyncRequestBody} from an {@link InputStream}.
      *
      * <p>An {@link ExecutorService} is required in order to perform the blocking data reads, to prevent blocking the
      * non-blocking event loop threads owned by the SDK.
@@ -239,7 +307,7 @@ static BlockingOutputStreamAsyncRequestBody forBlockingOutputStream(Long content
     }
 
     /**
-     * Creates a {@link AsyncRequestBody} with no content.
+     * Creates an {@link AsyncRequestBody} with no content.
      *
      * @return AsyncRequestBody instance.
      */