Properly release underlying buffer before passing it to WebSocket han…

…dler (#2715)

* Properly release underlying buffer before passing it to handler.

* Releases data chunks after passing them to Tyrus without any copying. Reports an error and closes connection if Tyrus is unable to handle the data. Finally, fixed a problem related to subscription requests.

Signed-off-by: Santiago Pericasgeertsen <santiago.pericasgeertsen@oracle.com>

* Removed unused logger.

Signed-off-by: Santiago Pericasgeertsen <santiago.pericasgeertsen@oracle.com>

* Fixed checkstyle.

Signed-off-by: Santiago Pericasgeertsen <santiago.pericasgeertsen@oracle.com>

webserver/tyrus/src/main/java/io/helidon/webserver/tyrus/TyrusReaderSubscriber.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2020 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021 Oracle and/or its affiliates. All rights reserved.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -19,7 +19,6 @@
 import java.nio.ByteBuffer;
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Flow;
-import java.util.logging.Logger;
 
 import javax.websocket.CloseReason;
 
@@ -34,7 +33,6 @@
  * Class TyrusReaderSubscriber.
  */
 public class TyrusReaderSubscriber implements Flow.Subscriber<DataChunk> {
-    private static final Logger LOGGER = Logger.getLogger(TyrusSupport.class.getName());
 
     private static final int MAX_RETRIES = 5;
     private static final CloseReason CONNECTION_CLOSED = new CloseReason(NORMAL_CLOSURE, "Connection closed");
@@ -63,34 +61,55 @@ public void onSubscribe(Flow.Subscription subscription) {
 
     @Override
     public void onNext(DataChunk item) {
-        if (executorService == null) {
+        if (subscription != null) {
+            if (executorService == null) {
+                submitDataChunk(item);
+            } else {
+                executorService.submit(() -> submitDataChunk(item));
+            }
+        } else {
+            item.release();
+        }
+    }
+
+    /**
+     * Submits all data in a chunk and requests one more if successful.
+     *
+     * @param item a data chunk
+     */
+    private void submitDataChunk(DataChunk item) {
+        try {
             for (ByteBuffer byteBuffer : item.data()) {
                 submitBuffer(byteBuffer);
             }
-        } else {
-            executorService.submit(() -> {
-                for (ByteBuffer byteBuffer : item.data()) {
-                    submitBuffer(byteBuffer);
-                }
-            });
+        } finally {
+            item.release();
+        }
+        if (subscription != null) {
+            subscription.request(1L);
         }
     }
 
     /**
-     * Submits data buffer to Tyrus. Retries a few times to make sure the entire buffer
-     * is consumed or logs an error.
+     * Submits single buffer to Tyrus. Retries a few times to make sure the entire buffer
+     * is consumed.
      *
      * @param data Data buffer.
      */
     private void submitBuffer(ByteBuffer data) {
+        // Pass all data to Tyrus spi
         int retries = MAX_RETRIES;
         while (data.remaining() > 0 && retries-- > 0) {
             connection.getReadHandler().handle(data);
         }
+
+        // If we can't push all data to Tyrus, cancel and report problem
         if (retries == 0) {
-            LOGGER.warning("Tyrus did not consume all data buffer after " + MAX_RETRIES + " retries");
+            subscription.cancel();
+            subscription = null;
+            connection.close(new CloseReason(UNEXPECTED_CONDITION, "Tyrus did not "
+                    + "consume all data after " + MAX_RETRIES + " retries"));
         }
-        subscription.request(1L);
     }
 
     @Override