wip

server/src/main/java/org/opensearch/transport/InboundAggregator.java

@@ -128,7 +128,7 @@ public ProtocolInboundMessage finishAggregation() throws IOException {
         }
 
         final BreakerControl breakerControl = new BreakerControl(circuitBreaker);
-        final NativeInboundMessage aggregated = new NativeInboundMessage(currentHeader, releasableContent, breakerControl);
+        final ProtocolInboundMessage aggregated = new ProtocolInboundMessage(currentHeader, releasableContent, breakerControl);
         boolean success = false;
         try {
             if (aggregated.getHeader().needsToReadVariableHeader()) {
@@ -143,7 +143,7 @@ public ProtocolInboundMessage finishAggregation() throws IOException {
             if (isShortCircuited()) {
                 aggregated.close();
                 success = true;
-                return new NativeInboundMessage(aggregated.getHeader(), aggregationException);
+                return new ProtocolInboundMessage(aggregated.getHeader(), aggregationException);
             } else {
                 success = true;
                 return aggregated;

server/src/main/java/org/opensearch/transport/InboundBytesHandler.java

@@ -9,24 +9,144 @@
 package org.opensearch.transport;
 
 import org.opensearch.common.bytes.ReleasableBytesReference;
+import org.opensearch.common.lease.Releasable;
+import org.opensearch.common.lease.Releasables;
+import org.opensearch.core.common.bytes.CompositeBytesReference;
+import org.opensearch.transport.nativeprotocol.NativeInboundMessage;
 
-import java.io.Closeable;
 import java.io.IOException;
+import java.util.ArrayDeque;
+import java.util.ArrayList;
 import java.util.function.BiConsumer;
 
 /**
- * Interface for handling inbound bytes. Can be implemented by different transport protocols.
+ * Handler for inbound bytes for the native protocol.
  */
-public interface InboundBytesHandler extends Closeable {
+class InboundBytesHandler {
+
+    private static final ThreadLocal<ArrayList<Object>> fragmentList = ThreadLocal.withInitial(ArrayList::new);
+
+    private final ArrayDeque<ReleasableBytesReference> pending;
+    private final InboundDecoder decoder;
+    private final InboundAggregator aggregator;
+    private final StatsTracker statsTracker;
+    private boolean isClosed = false;
+
+    InboundBytesHandler(
+        ArrayDeque<ReleasableBytesReference> pending,
+        InboundDecoder decoder,
+        InboundAggregator aggregator,
+        StatsTracker statsTracker
+    ) {
+        this.pending = pending;
+        this.decoder = decoder;
+        this.aggregator = aggregator;
+        this.statsTracker = statsTracker;
+    }
+
+    public void close() {
+        isClosed = true;
+    }
 
     public void doHandleBytes(
         TcpChannel channel,
         ReleasableBytesReference reference,
         BiConsumer<TcpChannel, ProtocolInboundMessage> messageHandler
-    ) throws IOException;
+    ) throws IOException {
+        final ArrayList<Object> fragments = fragmentList.get();
+        boolean continueHandling = true;
+
+        while (continueHandling && isClosed == false) {
+            boolean continueDecoding = true;
+            while (continueDecoding && pending.isEmpty() == false) {
+                try (ReleasableBytesReference toDecode = getPendingBytes()) {
+                    final int bytesDecoded = decoder.decode(toDecode, fragments::add);
+                    if (bytesDecoded != 0) {
+                        releasePendingBytes(bytesDecoded);
+                        if (fragments.isEmpty() == false && endOfMessage(fragments.get(fragments.size() - 1))) {
+                            continueDecoding = false;
+                        }
+                    } else {
+                        continueDecoding = false;
+                    }
+                }
+            }
+
+            if (fragments.isEmpty()) {
+                continueHandling = false;
+            } else {
+                try {
+                    forwardFragments(channel, fragments, messageHandler);
+                } finally {
+                    for (Object fragment : fragments) {
+                        if (fragment instanceof ReleasableBytesReference) {
+                            ((ReleasableBytesReference) fragment).close();
+                        }
+                    }
+                    fragments.clear();
+                }
+            }
+        }
+    }
 
-    public boolean canHandleBytes(ReleasableBytesReference reference);
+    private ReleasableBytesReference getPendingBytes() {
+        if (pending.size() == 1) {
+            return pending.peekFirst().retain();
+        } else {
+            final ReleasableBytesReference[] bytesReferences = new ReleasableBytesReference[pending.size()];
+            int index = 0;
+            for (ReleasableBytesReference pendingReference : pending) {
+                bytesReferences[index] = pendingReference.retain();
+                ++index;
+            }
+            final Releasable releasable = () -> Releasables.closeWhileHandlingException(bytesReferences);
+            return new ReleasableBytesReference(CompositeBytesReference.of(bytesReferences), releasable);
+        }
+    }
+
+    private void releasePendingBytes(int bytesConsumed) {
+        int bytesToRelease = bytesConsumed;
+        while (bytesToRelease != 0) {
+            try (ReleasableBytesReference reference = pending.pollFirst()) {
+                assert reference != null;
+                if (bytesToRelease < reference.length()) {
+                    pending.addFirst(reference.retainedSlice(bytesToRelease, reference.length() - bytesToRelease));
+                    bytesToRelease -= bytesToRelease;
+                } else {
+                    bytesToRelease -= reference.length();
+                }
+            }
+        }
+    }
+
+    private boolean endOfMessage(Object fragment) {
+        return fragment == InboundDecoder.PING || fragment == InboundDecoder.END_CONTENT || fragment instanceof Exception;
+    }
+
+    private void forwardFragments(
+        TcpChannel channel,
+        ArrayList<Object> fragments,
+        BiConsumer<TcpChannel, ProtocolInboundMessage> messageHandler
+    ) throws IOException {
+        for (Object fragment : fragments) {
+            if (fragment instanceof Header) {
+                assert aggregator.isAggregating() == false;
+                aggregator.headerReceived((Header) fragment);
+            } else if (fragment == InboundDecoder.PING) {
+                assert aggregator.isAggregating() == false;
+                messageHandler.accept(channel, ProtocolInboundMessage.PING);
+            } else if (fragment == InboundDecoder.END_CONTENT) {
+                assert aggregator.isAggregating();
+                try (ProtocolInboundMessage aggregated = aggregator.finishAggregation()) {
+                    statsTracker.markMessageReceived();
+                    messageHandler.accept(channel, aggregated);
+                }
+            } else {
+                assert aggregator.isAggregating();
+                assert fragment instanceof ReleasableBytesReference;
+                aggregator.aggregate((ReleasableBytesReference) fragment);
+            }
+        }
+    }
 
-    @Override
-    void close();
 }

server/src/main/java/org/opensearch/transport/InboundPipeline.java

@@ -38,11 +38,9 @@
 import org.opensearch.common.lease.Releasables;
 import org.opensearch.common.util.PageCacheRecycler;
 import org.opensearch.core.common.breaker.CircuitBreaker;
-import org.opensearch.transport.nativeprotocol.NativeInboundBytesHandler;
 
 import java.io.IOException;
 import java.util.ArrayDeque;
-import java.util.List;
 import java.util.function.BiConsumer;
 import java.util.function.Function;
 import java.util.function.LongSupplier;
@@ -94,7 +92,7 @@ public InboundPipeline(
         this.statsTracker = statsTracker;
         this.decoder = decoder;
         this.aggregator = aggregator;
-        this.bytesHandler = new NativeInboundBytesHandler(pending, decoder, aggregator, statsTracker);
+        this.bytesHandler = new InboundBytesHandler(pending, decoder, aggregator, statsTracker);
         this.messageHandler = messageHandler;
     }
 

server/src/main/java/org/opensearch/transport/NativeMessageHandler.java

@@ -119,18 +119,17 @@ public void messageReceived(
         long slowLogThresholdMs,
         TransportMessageListener messageListener
     ) throws IOException {
-        NativeInboundMessage inboundMessage = (NativeInboundMessage) message;
-        TransportLogger.logInboundMessage(channel, inboundMessage);
-        if (inboundMessage.isPing()) {
+        TransportLogger.logInboundMessage(channel, message);
+        if (message.isPing()) {
             keepAlive.receiveKeepAlive(channel);
         } else {
-            handleMessage(channel, inboundMessage, startTime, slowLogThresholdMs, messageListener);
+            handleMessage(channel, message, startTime, slowLogThresholdMs, messageListener);
         }
     }
 
     private void handleMessage(
         TcpChannel channel,
-        NativeInboundMessage message,
+        ProtocolInboundMessage message,
         long startTime,
         long slowLogThresholdMs,
         TransportMessageListener messageListener
@@ -202,7 +201,7 @@ private Map<String, Collection<String>> extractHeaders(Map<String, String> heade
     private <T extends TransportRequest> void handleRequest(
         TcpChannel channel,
         Header header,
-        NativeInboundMessage message,
+        ProtocolInboundMessage message,
         TransportMessageListener messageListener
     ) throws IOException {
         final String action = header.getActionName();

server/src/main/java/org/opensearch/transport/ProtocolInboundMessage.java

@@ -8,63 +8,64 @@
 
 package org.opensearch.transport;
 
+import java.io.IOException;
+
 import org.opensearch.common.annotation.PublicApi;
 import org.opensearch.common.bytes.ReleasableBytesReference;
 import org.opensearch.common.lease.Releasable;
 import org.opensearch.common.lease.Releasables;
+import org.opensearch.common.util.io.IOUtils;
+import org.opensearch.core.common.io.stream.StreamInput;
 
 /**
- * Base class for inbound data as a message.
- * Different implementations are used for different protocols.
+ * Inbound data as a message.
  *
  * @opensearch.internal
  */
 @PublicApi(since = "2.14.0")
-public abstract class ProtocolInboundMessage implements Releasable {
+public class ProtocolInboundMessage implements Releasable {
+
+    static final ProtocolInboundMessage PING = new ProtocolInboundMessage(null, null, null, true, null);
 
     protected final Header header;
     protected final ReleasableBytesReference content;
     protected final Exception exception;
     protected final boolean isPing;
     private Releasable breakerRelease;
+    private StreamInput streamInput;
 
-    public ProtocolInboundMessage(Header header, ReleasableBytesReference content, Releasable breakerRelease) {
-        this.header = header;
-        this.content = content;
-        this.breakerRelease = breakerRelease;
-        this.exception = null;
-        this.isPing = false;
+    ProtocolInboundMessage(Header header, ReleasableBytesReference content, Releasable breakerRelease) {
+        this(header,content, null, false, breakerRelease);
     }
 
-    public ProtocolInboundMessage(Header header, Exception exception) {
-        this.header = header;
-        this.content = null;
-        this.breakerRelease = null;
-        this.exception = exception;
-        this.isPing = false;
+    ProtocolInboundMessage(Header header, Exception exception) {
+        this(header, null, exception, false, null);
     }
 
-    public ProtocolInboundMessage(Header header, boolean isPing) {
+    private ProtocolInboundMessage(Header header, ReleasableBytesReference content, Exception exception, boolean isPing, Releasable breakerRelease) {
         this.header = header;
-        this.content = null;
-        this.breakerRelease = null;
-        this.exception = null;
+        this.content = content;
+        this.exception = exception;
         this.isPing = isPing;
+        this.breakerRelease = breakerRelease;
     }
 
     TransportProtocol getTransportProtocol() {
+        if (isPing) {
+            return TransportProtocol.NATIVE;
+        }
         return header.getTransportProtocol();
     }
 
     public String getProtocol() {
         return header.getTransportProtocol().toString();
     }
 
-    public Header getHeader() {
+    Header getHeader() {
         return header;
     }
 
-    public int getContentLength() {
+    int getContentLength() {
         if (content == null) {
             return 0;
         } else {
@@ -76,15 +77,15 @@ public Exception getException() {
         return exception;
     }
 
-    public boolean isPing() {
+    boolean isPing() {
         return isPing;
     }
 
-    public boolean isShortCircuit() {
+    boolean isShortCircuit() {
         return exception != null;
     }
 
-    public Releasable takeBreakerReleaseControl() {
+    Releasable takeBreakerReleaseControl() {
         final Releasable toReturn = breakerRelease;
         breakerRelease = null;
         if (toReturn != null) {
@@ -94,15 +95,23 @@ public Releasable takeBreakerReleaseControl() {
         }
     }
 
-
+    StreamInput openOrGetStreamInput() throws IOException {
+        assert isPing == false && content != null;
+        if (streamInput == null) {
+            streamInput = content.streamInput();
+            streamInput.setVersion(header.getVersion());
+        }
+        return streamInput;
+    }
 
     @Override
     public void close() {
+        IOUtils.closeWhileHandlingException(streamInput);
         Releasables.closeWhileHandlingException(content, breakerRelease);
     }
 
     @Override
     public String toString() {
-        return "InboundMessage{" + header + "}";
+        return "ProtocolInboundMessage{" + header + "}";
     }
 }

server/src/main/java/org/opensearch/transport/TransportLogger.java

@@ -65,7 +65,7 @@ static void logInboundMessage(TcpChannel channel, BytesReference message) {
         }
     }
 
-    static void logInboundMessage(TcpChannel channel, NativeInboundMessage message) {
+    static void logInboundMessage(TcpChannel channel, ProtocolInboundMessage message) {
         if (logger.isTraceEnabled()) {
             try {
                 String logMessage = format(channel, message, "READ");
@@ -137,7 +137,7 @@ private static String format(TcpChannel channel, BytesReference message, String
         return sb.toString();
     }
 
-    private static String format(TcpChannel channel, NativeInboundMessage message, String event) throws IOException {
+    private static String format(TcpChannel channel, ProtocolInboundMessage message, String event) throws IOException {
         final StringBuilder sb = new StringBuilder();
         sb.append(channel);