Starting point for reactive WebSocket support

Includes basic abstractions and an RxNetty support to start.

Issue: SPR-14527

build.gradle

@@ -802,6 +802,11 @@ project("spring-web-reactive") {
 		optional("org.freemarker:freemarker:${freemarkerVersion}")
 		optional "org.apache.httpcomponents:httpclient:${httpclientVersion}"
 		optional('org.webjars:webjars-locator:0.32')
+		optional("io.reactivex:rxnetty-http:${rxnettyVersion}") {
+			exclude group: 'io.reactivex', module: 'rxjava'
+		}
+		optional("io.reactivex:rxjava:${rxjavaVersion}")
+		optional("io.reactivex:rxjava-reactive-streams:${rxjavaAdapterVersion}")
 		testCompile("io.projectreactor.addons:reactor-test:${reactorCoreVersion}")
 		testCompile("javax.validation:validation-api:${beanvalVersion}")
 		testCompile("org.hibernate:hibernate-validator:${hibval5Version}")
@@ -810,12 +815,7 @@ project("spring-web-reactive") {
 		testCompile("org.eclipse.jetty:jetty-server:${jettyVersion}")
 		testCompile("org.eclipse.jetty:jetty-servlet:${jettyVersion}")
 		testCompile("io.projectreactor.ipc:reactor-netty:${reactorNettyVersion}")
-		testCompile("io.reactivex:rxnetty-http:${rxnettyVersion}") {
-			exclude group: 'io.reactivex', module: 'rxjava'
-		}
-		testCompile("io.reactivex:rxjava:${rxjavaVersion}")
 		testCompile "io.reactivex.rxjava2:rxjava:${rxjava2Version}"
-		testCompile("io.reactivex:rxjava-reactive-streams:${rxjavaAdapterVersion}")
 		testCompile("io.undertow:undertow-core:${undertowVersion}")
 		testCompile("org.jboss.xnio:xnio-api:${xnioVersion}")
 		testCompile("com.fasterxml:aalto-xml:1.0.0")

spring-web-reactive/src/main/java/org/springframework/web/reactive/socket/CloseStatus.java

@@ -0,0 +1,213 @@
+/*
+ * Copyright 2002-2014 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.web.reactive.socket;
+
+import org.springframework.util.Assert;
+import org.springframework.util.ObjectUtils;
+
+/**
+ * Representation of WebSocket "close" status codes and reasons. Status codes
+ * in the 1xxx range are pre-defined by the protocol.
+ *
+ * <p>See <a href="https://tools.ietf.org/html/rfc6455#section-7.4.1">
+ *     RFC 6455, Section 7.4.1 "Defined Status Codes"</a>.
+ *
+ * @author Rossen Stoyanchev
+ * @since 5.0
+ */
+public final class CloseStatus {
+
+	/**
+	 * "1000 indicates a normal closure, meaning that the purpose for which the connection
+	 * was established has been fulfilled."
+	 */
+	public static final CloseStatus NORMAL = new CloseStatus(1000);
+
+	/**
+	 * "1001 indicates that an endpoint is "going away", such as a server going down or a
+	 * browser having navigated away from a page."
+	 */
+	public static final CloseStatus GOING_AWAY = new CloseStatus(1001);
+
+	/**
+	 * "1002 indicates that an endpoint is terminating the connection due to a protocol
+	 * error."
+	 */
+	public static final CloseStatus PROTOCOL_ERROR  = new CloseStatus(1002);
+
+	/**
+	 * "1003 indicates that an endpoint is terminating the connection because it has
+	 * received a type of data it cannot accept (e.g., an endpoint that understands only
+	 * text data MAY send this if it receives a binary message)."
+	 */
+	public static final CloseStatus NOT_ACCEPTABLE = new CloseStatus(1003);
+
+	// 10004: Reserved.
+	// The specific meaning might be defined in the future.
+
+	/**
+	 * "1005 is a reserved value and MUST NOT be set as a status code in a Close control
+	 * frame by an endpoint. It is designated for use in applications expecting a status
+	 * code to indicate that no status code was actually present."
+	 */
+	public static final CloseStatus NO_STATUS_CODE = new CloseStatus(1005);
+
+	/**
+	 * "1006 is a reserved value and MUST NOT be set as a status code in a Close control
+	 * frame by an endpoint. It is designated for use in applications expecting a status
+	 * code to indicate that the connection was closed abnormally, e.g., without sending
+	 * or receiving a Close control frame."
+	 */
+	public static final CloseStatus NO_CLOSE_FRAME = new CloseStatus(1006);
+
+	/**
+	 * "1007 indicates that an endpoint is terminating the connection because it has
+	 * received data within a message that was not consistent with the type of the message
+	 * (e.g., non-UTF-8 [RFC3629] data within a text message)."
+	 */
+	public static final CloseStatus BAD_DATA = new CloseStatus(1007);
+
+	/**
+	 * "1008 indicates that an endpoint is terminating the connection because it has
+	 * received a message that violates its policy. This is a generic status code that can
+	 * be returned when there is no other more suitable status code (e.g., 1003 or 1009)
+	 * or if there is a need to hide specific details about the policy."
+	 */
+	public static final CloseStatus POLICY_VIOLATION = new CloseStatus(1008);
+
+	/**
+	 * "1009 indicates that an endpoint is terminating the connection because it has
+	 * received a message that is too big for it to process."
+	 */
+	public static final CloseStatus TOO_BIG_TO_PROCESS = new CloseStatus(1009);
+
+	/**
+	 * "1010 indicates that an endpoint (client) is terminating the connection because it
+	 * has expected the server to negotiate one or more extension, but the server didn't
+	 * return them in the response message of the WebSocket handshake. The list of
+	 * extensions that are needed SHOULD appear in the /reason/ part of the Close frame.
+	 * Note that this status code is not used by the server, because it can fail the
+	 * WebSocket handshake instead."
+	 */
+	public static final CloseStatus REQUIRED_EXTENSION = new CloseStatus(1010);
+
+	/**
+	 * "1011 indicates that a server is terminating the connection because it encountered
+	 * an unexpected condition that prevented it from fulfilling the request."
+	 */
+	public static final CloseStatus SERVER_ERROR = new CloseStatus(1011);
+
+	/**
+	 * "1012 indicates that the service is restarted. A client may reconnect, and if it
+	 * chooses to do, should reconnect using a randomized delay of 5 - 30s."
+	 */
+	public static final CloseStatus SERVICE_RESTARTED = new CloseStatus(1012);
+
+	/**
+	 * "1013 indicates that the service is experiencing overload. A client should only
+	 * connect to a different IP (when there are multiple for the target) or reconnect to
+	 * the same IP upon user action."
+	 */
+	public static final CloseStatus SERVICE_OVERLOAD = new CloseStatus(1013);
+
+	/**
+	 * "1015 is a reserved value and MUST NOT be set as a status code in a Close control
+	 * frame by an endpoint. It is designated for use in applications expecting a status
+	 * code to indicate that the connection was closed due to a failure to perform a TLS
+	 * handshake (e.g., the server certificate can't be verified)."
+	 */
+	public static final CloseStatus TLS_HANDSHAKE_FAILURE = new CloseStatus(1015);
+
+
+	private final int code;
+
+	private final String reason;
+
+
+	/**
+	 * Create a new {@link CloseStatus} instance.
+	 * @param code the status code
+	 */
+	public CloseStatus(int code) {
+		this(code, null);
+	}
+
+	/**
+	 * Create a new {@link CloseStatus} instance.
+	 * @param code the status code
+	 * @param reason the reason
+	 */
+	public CloseStatus(int code, String reason) {
+		Assert.isTrue((code >= 1000 && code < 5000), "Invalid status code");
+		this.code = code;
+		this.reason = reason;
+	}
+
+
+	/**
+	 * Return the status code.
+	 */
+	public int getCode() {
+		return this.code;
+	}
+
+	/**
+	 * Return the reason, or {@code null} if none.
+	 */
+	public String getReason() {
+		return this.reason;
+	}
+
+	/**
+	 * Create a new {@link CloseStatus} from this one with the specified reason.
+	 * @param reason the reason
+	 * @return a new {@link CloseStatus} instance
+	 */
+	public CloseStatus withReason(String reason) {
+		Assert.hasText(reason, "Reason must not be empty");
+		return new CloseStatus(this.code, reason);
+	}
+
+
+	public boolean equalsCode(CloseStatus other) {
+		return (this.code == other.code);
+	}
+
+	@Override
+	public boolean equals(Object other) {
+		if (this == other) {
+			return true;
+		}
+		if (!(other instanceof CloseStatus)) {
+			return false;
+		}
+		CloseStatus otherStatus = (CloseStatus) other;
+		return (this.code == otherStatus.code &&
+				ObjectUtils.nullSafeEquals(this.reason, otherStatus.reason));
+	}
+
+	@Override
+	public int hashCode() {
+		return this.code * 29 + ObjectUtils.nullSafeHashCode(this.reason);
+	}
+
+	@Override
+	public String toString() {
+		return "CloseStatus[code=" + this.code + ", reason=" + this.reason + "]";
+	}
+
+}

spring-web-reactive/src/main/java/org/springframework/web/reactive/socket/WebSocketHandler.java

@@ -0,0 +1,46 @@
+/*
+ * Copyright 2002-2016 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.web.reactive.socket;
+
+import java.util.Collections;
+import java.util.List;
+
+import reactor.core.publisher.Mono;
+
+/**
+ * Handler for a WebSocket-style session interaction.
+ *
+ * @author Rossen Stoyanchev
+ * @since 5.0
+ */
+public interface WebSocketHandler {
+
+	/**
+	 * Return the list of sub-protocols supported by this handler.
+	 * <p>By default an empty list is returned.
+	 */
+	default List<String> getSubProtocols() {
+		return Collections.emptyList();
+	}
+
+	/**
+	 * Handle the given WebSocket session.
+	 * @param session the session
+	 * @return signals completion for session handling
+	 */
+	Mono<Void> handle(WebSocketSession session);
+
+}

spring-web-reactive/src/main/java/org/springframework/web/reactive/socket/WebSocketMessage.java

@@ -0,0 +1,122 @@
+/*
+ * Copyright 2002-2016 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.web.reactive.socket;
+
+import org.springframework.core.io.buffer.DataBuffer;
+import org.springframework.util.Assert;
+import org.springframework.util.ObjectUtils;
+
+/**
+ * Representation of a WebSocket message.
+ * Use one of the static factory methods in this class to create a message.
+ *
+ * @author Rossen Stoyanchev
+ * @since 5.0
+ */
+public class WebSocketMessage {
+
+	private final Type type;
+
+	private final DataBuffer payload;
+
+
+	/**
+	 * Private constructor. See static factory methods.
+	 */
+	private WebSocketMessage(Type type, DataBuffer payload) {
+		Assert.notNull(type, "'type' must not be null");
+		Assert.notNull(payload, "'payload' must not be null");
+		this.type = type;
+		this.payload = payload;
+	}
+
+
+	/**
+	 * Return the message type (text, binary, etc).
+	 */
+	public Type getType() {
+		return this.type;
+	}
+
+	/**
+	 * Return the message payload.
+	 */
+	public DataBuffer getPayload() {
+		return this.payload;
+	}
+
+
+	@Override
+	public boolean equals(Object other) {
+		if (this == other) {
+			return true;
+		}
+		if (!(other instanceof WebSocketMessage)) {
+			return false;
+		}
+		WebSocketMessage otherMessage = (WebSocketMessage) other;
+		return (this.type.equals(otherMessage.type) &&
+				ObjectUtils.nullSafeEquals(this.payload, otherMessage.payload));
+	}
+
+	@Override
+	public int hashCode() {
+		return this.type.hashCode() * 29 + this.payload.hashCode();
+	}
+
+
+	/**
+	 * Factory method to create a text WebSocket message.
+	 */
+	public static WebSocketMessage text(DataBuffer payload) {
+		return create(Type.TEXT, payload);
+	}
+
+	/**
+	 * Factory method to create a binary WebSocket message.
+	 */
+	public static WebSocketMessage binary(DataBuffer payload) {
+		return create(Type.BINARY, payload);
+	}
+
+	/**
+	 * Factory method to create a ping WebSocket message.
+	 */
+	public static WebSocketMessage ping(DataBuffer payload) {
+		return create(Type.PING, payload);
+	}
+
+	/**
+	 * Factory method to create a pong WebSocket message.
+	 */
+	public static WebSocketMessage pong(DataBuffer payload) {
+		return create(Type.PONG, payload);
+	}
+
+	/**
+	 * Factory method to create a WebSocket message of the given type.
+	 */
+	public static WebSocketMessage create(Type type, DataBuffer payload) {
+		return new WebSocketMessage(type, payload);
+	}
+
+
+	/**
+	 * WebSocket message types.
+	 */
+	public enum Type { TEXT, BINARY, PING, PONG }
+
+}

spring-web-reactive/src/main/java/org/springframework/web/reactive/socket/WebSocketSession.java

@@ -0,0 +1,72 @@
+/*
+ * Copyright 2002-2016 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.web.reactive.socket;
+
+import java.net.URI;
+
+import org.reactivestreams.Publisher;
+import reactor.core.publisher.Flux;
+import reactor.core.publisher.Mono;
+
+import org.springframework.core.io.buffer.DataBuffer;
+
+/**
+ * Representation for a WebSocket session.
+ *
+ * @author Rossen Stoyanchev
+ * @since 5.0
+ */
+public interface WebSocketSession {
+
+	/**
+	 * Return the id for the session.
+	 */
+	String getId();
+
+	/**
+	 * Return the WebSocket endpoint URI.
+	 */
+	URI getUri();
+
+	/**
+	 * Get the flux of incoming messages.
+	 * <p><strong>Note:</strong> the caller of this method is responsible for
+	 * releasing the DataBuffer payload of each message after consuming it
+	 * on runtimes where a {@code PooledByteBuffer} is used such as Netty.
+	 * @see org.springframework.core.io.buffer.DataBufferUtils#release(DataBuffer)
+	 */
+	Flux<WebSocketMessage> receive();
+
+	/**
+	 * Write the given messages to the WebSocket connection.
+	 * @param messages the messages to write
+	 */
+	Mono<Void> send(Publisher<WebSocketMessage> messages);
+
+	/**
+	 * Close the WebSocket session with {@link CloseStatus#NORMAL}.
+	 */
+	default Mono<Void> close() {
+		return close(CloseStatus.NORMAL);
+	}
+
+	/**
+	 * Close the WebSocket session with the given status.
+	 * @param status the close status
+	 */
+	Mono<Void> close(CloseStatus status);
+
+}

spring-web-reactive/src/main/java/org/springframework/web/reactive/socket/adapter/RxNettyWebSocketHandlerAdapter.java

@@ -0,0 +1,71 @@
+/*
+ * Copyright 2002-2016 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.web.reactive.socket.adapter;
+
+import java.net.URI;
+
+import io.reactivex.netty.protocol.http.ws.WebSocketConnection;
+import reactor.core.publisher.Mono;
+import rx.Observable;
+import rx.RxReactiveStreams;
+
+import org.springframework.core.io.buffer.NettyDataBufferFactory;
+import org.springframework.http.server.reactive.ServerHttpRequest;
+import org.springframework.http.server.reactive.ServerHttpResponse;
+import org.springframework.util.Assert;
+import org.springframework.web.reactive.socket.WebSocketHandler;
+
+/**
+ * RxNetty {@code WebSocketHandler} implementation adapting and delegating to a
+ * Spring {@link WebSocketHandler}.
+ *
+ * @author Rossen Stoyanchev
+ * @since 5.0
+ */
+public class RxNettyWebSocketHandlerAdapter
+		implements io.reactivex.netty.protocol.http.ws.server.WebSocketHandler {
+
+	private final URI uri;
+
+	private final NettyDataBufferFactory bufferFactory;
+
+	private final WebSocketHandler handler;
+
+
+	public RxNettyWebSocketHandlerAdapter(ServerHttpRequest request, ServerHttpResponse response,
+			WebSocketHandler handler) {
+
+		Assert.notNull("'request' is required");
+		Assert.notNull("'response' is required");
+		Assert.notNull("'handler' handler is required");
+
+		this.uri = request.getURI();
+		this.bufferFactory = (NettyDataBufferFactory) response.bufferFactory();
+		this.handler = handler;
+	}
+
+
+	@Override
+	public Observable<Void> handle(WebSocketConnection connection) {
+		Mono<Void> result = this.handler.handle(createSession(connection));
+		return RxReactiveStreams.toObservable(result);
+	}
+
+	private RxNettyWebSocketSession createSession(WebSocketConnection conn) {
+		return new RxNettyWebSocketSession(conn, this.uri, this.bufferFactory);
+	}
+
+}

spring-web-reactive/src/main/java/org/springframework/web/reactive/socket/adapter/RxNettyWebSocketSession.java

@@ -0,0 +1,143 @@
+/*
+ * Copyright 2002-2016 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.web.reactive.socket.adapter;
+
+import java.net.URI;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+import io.netty.buffer.ByteBuf;
+import io.netty.handler.codec.http.websocketx.BinaryWebSocketFrame;
+import io.netty.handler.codec.http.websocketx.CloseWebSocketFrame;
+import io.netty.handler.codec.http.websocketx.PingWebSocketFrame;
+import io.netty.handler.codec.http.websocketx.PongWebSocketFrame;
+import io.netty.handler.codec.http.websocketx.TextWebSocketFrame;
+import io.netty.handler.codec.http.websocketx.WebSocketFrame;
+import io.reactivex.netty.protocol.http.ws.WebSocketConnection;
+import org.reactivestreams.Publisher;
+import reactor.core.publisher.Flux;
+import reactor.core.publisher.Mono;
+import rx.Observable;
+import rx.RxReactiveStreams;
+
+import org.springframework.core.io.buffer.NettyDataBuffer;
+import org.springframework.core.io.buffer.NettyDataBufferFactory;
+import org.springframework.util.Assert;
+import org.springframework.util.ObjectUtils;
+import org.springframework.web.reactive.socket.CloseStatus;
+import org.springframework.web.reactive.socket.WebSocketMessage;
+
+/**
+ *
+ * @author Rossen Stoyanchev
+ * @since 5.0
+ */
+public class RxNettyWebSocketSession extends WebSocketSessionSupport<WebSocketConnection> {
+
+	private static final Map<Class<?>, WebSocketMessage.Type> MESSAGE_TYPES;
+
+	static {
+		MESSAGE_TYPES = new HashMap<>(4);
+		MESSAGE_TYPES.put(TextWebSocketFrame.class, WebSocketMessage.Type.TEXT);
+		MESSAGE_TYPES.put(BinaryWebSocketFrame.class, WebSocketMessage.Type.BINARY);
+		MESSAGE_TYPES.put(PingWebSocketFrame.class, WebSocketMessage.Type.PING);
+		MESSAGE_TYPES.put(PongWebSocketFrame.class, WebSocketMessage.Type.PONG);
+	}
+
+
+	private final String id;
+
+	private final URI uri;
+
+	private final NettyDataBufferFactory bufferFactory;
+
+
+	public RxNettyWebSocketSession(WebSocketConnection conn, URI uri, NettyDataBufferFactory factory) {
+		super(conn);
+		Assert.notNull(uri, "'uri' is required.");
+		Assert.notNull(uri, "'bufferFactory' is required.");
+		this.id = ObjectUtils.getIdentityHexString(getDelegate());
+		this.uri = uri;
+		this.bufferFactory = factory;
+	}
+
+
+	@Override
+	public String getId() {
+		return this.id;
+	}
+
+	@Override
+	public URI getUri() {
+		return this.uri;
+	}
+
+	@Override
+	public Flux<WebSocketMessage> receive() {
+		return Flux.from(RxReactiveStreams.toPublisher(getDelegate().getInput()))
+				.filter(frame -> !(frame instanceof CloseWebSocketFrame))
+				.window()
+				.concatMap(flux -> flux.takeUntil(WebSocketFrame::isFinalFragment).buffer())
+				.map(this::toMessage);
+	}
+
+	@SuppressWarnings("OptionalGetWithoutIsPresent")
+	private WebSocketMessage toMessage(List<WebSocketFrame> frames) {
+		Class<?> frameType = frames.get(0).getClass();
+		if (frames.size() == 1) {
+			NettyDataBuffer buffer = this.bufferFactory.wrap(frames.get(0).content());
+			return WebSocketMessage.create(MESSAGE_TYPES.get(frameType), buffer);
+		}
+		return frames.stream()
+				.map(socketFrame -> bufferFactory.wrap(socketFrame.content()))
+				.reduce(NettyDataBuffer::write)
+				.map(buffer -> WebSocketMessage.create(MESSAGE_TYPES.get(frameType), buffer))
+				.get();
+	}
+
+	@Override
+	public Mono<Void> send(Publisher<WebSocketMessage> messages) {
+		Observable<WebSocketFrame> frames = RxReactiveStreams.toObservable(messages).map(this::toFrame);
+		Observable<Void> completion = getDelegate().write(frames);
+		return Mono.from(RxReactiveStreams.toPublisher(completion));
+	}
+
+	private WebSocketFrame toFrame(WebSocketMessage message) {
+		ByteBuf byteBuf = NettyDataBufferFactory.toByteBuf(message.getPayload());
+		if (WebSocketMessage.Type.TEXT.equals(message.getType())) {
+			return new TextWebSocketFrame(byteBuf);
+		}
+		else if (WebSocketMessage.Type.BINARY.equals(message.getType())) {
+			return new BinaryWebSocketFrame(byteBuf);
+		}
+		else if (WebSocketMessage.Type.PING.equals(message.getType())) {
+			return new PingWebSocketFrame(byteBuf);
+		}
+		else if (WebSocketMessage.Type.BINARY.equals(message.getType())) {
+			return new PongWebSocketFrame(byteBuf);
+		}
+		else {
+			throw new IllegalArgumentException("Unexpected message type: " + message.getType());
+		}
+	}
+
+	@Override
+	protected Mono<Void> closeInternal(CloseStatus status) {
+		return Mono.from(RxReactiveStreams.toPublisher(getDelegate().close()));
+	}
+
+}

spring-web-reactive/src/main/java/org/springframework/web/reactive/socket/adapter/WebSocketSessionSupport.java

@@ -0,0 +1,77 @@
+/*
+ * Copyright 2002-2016 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.web.reactive.socket.adapter;
+
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+import reactor.core.publisher.Mono;
+
+import org.springframework.util.Assert;
+import org.springframework.web.reactive.socket.CloseStatus;
+import org.springframework.web.reactive.socket.WebSocketSession;
+
+/**
+ * Base class for {@link WebSocketSession} implementations wrapping and
+ * delegating to the native WebSocket session (or connection) of the underlying
+ * WebSocket runtime.
+ *
+ * @author Rossen Stoyanchev
+ * @since 5.0
+ */
+public abstract class WebSocketSessionSupport<T> implements WebSocketSession {
+
+	protected final Log logger = LogFactory.getLog(getClass());
+
+
+	private final T delegate;
+
+
+	/**
+	 * Create a new instance and associate the given attributes with it.
+	 * @param delegate the underlying WebSocket connection
+	 */
+	protected WebSocketSessionSupport(T delegate) {
+		Assert.notNull(delegate, "'delegate' session is required.");
+		this.delegate = delegate;
+	}
+
+
+	/**
+	 * Return the native session of the underlying runtime.
+	 */
+	public T getDelegate() {
+		return this.delegate;
+	}
+
+
+	@Override
+	public final Mono<Void> close(CloseStatus status) {
+		if (logger.isDebugEnabled()) {
+			logger.debug("Closing " + this);
+		}
+		return closeInternal(status);
+	}
+
+	protected abstract Mono<Void> closeInternal(CloseStatus status);
+
+
+	@Override
+	public String toString() {
+		return getClass().getSimpleName() + "[id=" + getId() + ", uri=" + getUri() + "]";
+	}
+
+}

spring-web-reactive/src/main/java/org/springframework/web/reactive/socket/adapter/package-info.java

@@ -0,0 +1,4 @@
+/**
+ * Classes adapting Spring's Reactive WebSocket API to and from WebSocket runtimes.
+ */
+package org.springframework.web.reactive.socket.adapter;

spring-web-reactive/src/main/java/org/springframework/web/reactive/socket/package-info.java

@@ -0,0 +1,4 @@
+/**
+ * Abstractions and support classes for WebSocket interactions.
+ */
+package org.springframework.web.reactive.socket;

spring-web-reactive/src/main/java/org/springframework/web/reactive/socket/server/RequestUpgradeStrategy.java

@@ -0,0 +1,51 @@
+/*
+ * Copyright 2002-2016 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.web.reactive.socket.server;
+
+import java.util.Map;
+
+import reactor.core.publisher.Mono;
+
+import org.springframework.http.server.reactive.ServerHttpRequest;
+import org.springframework.http.server.reactive.ServerHttpResponse;
+import org.springframework.web.reactive.socket.WebSocketHandler;
+import org.springframework.web.server.ServerWebExchange;
+
+/**
+ * A strategy for upgrading an HTTP request to a WebSocket interaction depending
+ * on the underlying HTTP runtime.
+ *
+ * <p>Typically there is one such strategy for every {@link ServerHttpRequest}
+ * and {@link ServerHttpResponse} implementation type except in the case of
+ * Servlet containers for which there is no standard API to upgrade a request.
+ * JSR-356 does have programmatic endpoint registration but that is only
+ * intended for use on startup and not per request.
+ *
+ * @author Rossen Stoyanchev
+ * @since 5.0
+ */
+public interface RequestUpgradeStrategy {
+
+	/**
+	 * Upgrade the request to a WebSocket interaction and adapt the given
+	 * Spring {@link WebSocketHandler} to the underlying runtime WebSocket API.
+	 * @param exchange the current exchange
+	 * @param webSocketHandler handler for WebSocket session
+	 * @return a completion Mono for the WebSocket session handling
+	 */
+	Mono<Void> upgrade(ServerWebExchange exchange, WebSocketHandler webSocketHandler);
+
+}

spring-web-reactive/src/main/java/org/springframework/web/reactive/socket/server/WebSocketService.java

@@ -0,0 +1,45 @@
+/*
+ * Copyright 2002-2016 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.web.reactive.socket.server;
+
+import reactor.core.publisher.Mono;
+
+import org.springframework.web.reactive.socket.WebSocketHandler;
+import org.springframework.web.reactive.socket.server.support.HandshakeWebSocketService;
+import org.springframework.web.server.ServerWebExchange;
+
+/**
+ * A service to delegate WebSocket-related HTTP requests to.
+ *
+ * <p>For a straight-up WebSocket endpoint this means handling the initial
+ * handshake request but for a SockJS endpoint this means handling all HTTP
+ * requests defined in the SockJS protocol.
+ *
+ * @author Rossen Stoyanchev
+ * @since 5.0
+ * @see HandshakeWebSocketService
+ */
+public interface WebSocketService {
+
+	/**
+	 * Handle the HTTP request and use the given {@link WebSocketHandler}.
+	 * @param exchange the current exchange
+	 * @param webSocketHandler handler for WebSocket session
+	 * @return a completion Mono for the WebSocket session handling
+	 */
+	Mono<Void> handleRequest(ServerWebExchange exchange, WebSocketHandler webSocketHandler);
+
+}

spring-web-reactive/src/main/java/org/springframework/web/reactive/socket/server/package-info.java

@@ -0,0 +1,4 @@
+/**
+ * Server support for WebSocket interactions.
+ */
+package org.springframework.web.reactive.socket.server;

spring-web-reactive/src/main/java/org/springframework/web/reactive/socket/server/support/HandshakeWebSocketService.java

@@ -0,0 +1,155 @@
+/*
+ * Copyright 2002-2016 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.web.reactive.socket.server.support;
+
+import java.util.Collections;
+import java.util.List;
+
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+import reactor.core.publisher.Mono;
+
+import org.springframework.http.HttpMethod;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.server.reactive.ServerHttpRequest;
+import org.springframework.http.server.reactive.ServerHttpResponse;
+import org.springframework.util.Assert;
+import org.springframework.util.ClassUtils;
+import org.springframework.util.ReflectionUtils;
+import org.springframework.web.reactive.socket.WebSocketHandler;
+import org.springframework.web.reactive.socket.server.RequestUpgradeStrategy;
+import org.springframework.web.reactive.socket.server.WebSocketService;
+import org.springframework.web.server.MethodNotAllowedException;
+import org.springframework.web.server.ServerWebExchange;
+
+/**
+ * A {@code WebSocketService} implementation that handles a WebSocket handshake
+ * and upgrades to a WebSocket interaction through the configured or
+ * auto-detected {@link RequestUpgradeStrategy}.
+ *
+ * @author Rossen Stoyanchev
+ * @since 5.0
+ */
+public class HandshakeWebSocketService implements WebSocketService {
+
+	private static final String SEC_WEBSOCKET_KEY = "Sec-WebSocket-Key";
+
+
+	private static final boolean rxNettyPresent = ClassUtils.isPresent(
+			"io.reactivex.netty.protocol.http.ws.WebSocketConnection",
+			HandshakeWebSocketService.class.getClassLoader());
+
+
+	protected static final Log logger = LogFactory.getLog(HandshakeWebSocketService.class);
+
+
+	private final RequestUpgradeStrategy upgradeStrategy;
+
+
+	/**
+	 * Default constructor automatic, classpath detection based discovery of the
+	 * {@link RequestUpgradeStrategy} to use.
+	 */
+	public HandshakeWebSocketService() {
+		this(initUpgradeStrategy());
+	}
+
+	/**
+	 * Alternative constructor with the {@link RequestUpgradeStrategy} to use.
+	 * @param upgradeStrategy the strategy to use
+	 */
+	public HandshakeWebSocketService(RequestUpgradeStrategy upgradeStrategy) {
+		Assert.notNull(upgradeStrategy, "'upgradeStrategy' is required");
+		this.upgradeStrategy = upgradeStrategy;
+	}
+
+	private static RequestUpgradeStrategy initUpgradeStrategy() {
+		String className;
+		if (rxNettyPresent) {
+			className = "RxNettyRequestUpgradeStrategy";
+		}
+		else {
+			throw new IllegalStateException("No suitable default RequestUpgradeStrategy found");
+		}
+
+		try {
+			className = HandshakeWebSocketService.class.getPackage().getName() + "." + className;
+			Class<?> clazz = ClassUtils.forName(className, HandshakeWebSocketService.class.getClassLoader());
+			return (RequestUpgradeStrategy) ReflectionUtils.accessibleConstructor(clazz).newInstance();
+		}
+		catch (Throwable ex) {
+			throw new IllegalStateException(
+					"Failed to instantiate RequestUpgradeStrategy: " + className, ex);
+		}
+	}
+
+
+	/**
+	 * Return the {@link RequestUpgradeStrategy} for WebSocket requests.
+	 */
+	public RequestUpgradeStrategy getUpgradeStrategy() {
+		return this.upgradeStrategy;
+	}
+
+
+	@Override
+	public Mono<Void> handleRequest(ServerWebExchange exchange, WebSocketHandler webSocketHandler) {
+
+		ServerHttpRequest request = exchange.getRequest();
+		ServerHttpResponse response = exchange.getResponse();
+
+		if (logger.isTraceEnabled()) {
+			logger.trace("Processing " + request.getMethod() + " " + request.getURI());
+		}
+
+		if (HttpMethod.GET != request.getMethod()) {
+			return Mono.error(new MethodNotAllowedException(
+					request.getMethod().name(), Collections.singleton("GET")));
+		}
+
+		if (!isWebSocketUpgrade(request)) {
+			response.setStatusCode(HttpStatus.BAD_REQUEST);
+			return response.setComplete();
+		}
+
+		return getUpgradeStrategy().upgrade(exchange, webSocketHandler);
+	}
+
+	private boolean isWebSocketUpgrade(ServerHttpRequest request) {
+		if (!"WebSocket".equalsIgnoreCase(request.getHeaders().getUpgrade())) {
+			if (logger.isErrorEnabled()) {
+				logger.error("Invalid 'Upgrade' header: " + request.getHeaders());
+			}
+			return false;
+		}
+		List<String> connectionValue = request.getHeaders().getConnection();
+		if (!connectionValue.contains("Upgrade") && !connectionValue.contains("upgrade")) {
+			if (logger.isErrorEnabled()) {
+				logger.error("Invalid 'Connection' header: " + request.getHeaders());
+			}
+			return false;
+		}
+		String key = request.getHeaders().getFirst(SEC_WEBSOCKET_KEY);
+		if (key == null) {
+			if (logger.isErrorEnabled()) {
+				logger.error("Missing \"Sec-WebSocket-Key\" header");
+			}
+			return false;
+		}
+		return true;
+	}
+
+}

spring-web-reactive/src/main/java/org/springframework/web/reactive/socket/server/support/WebSocketHandlerAdapter.java

@@ -0,0 +1,75 @@
+/*
+ * Copyright 2002-2016 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.web.reactive.socket.server.support;
+
+import reactor.core.publisher.Mono;
+
+import org.springframework.util.Assert;
+import org.springframework.web.reactive.DispatcherHandler;
+import org.springframework.web.reactive.HandlerAdapter;
+import org.springframework.web.reactive.HandlerResult;
+import org.springframework.web.reactive.socket.WebSocketHandler;
+import org.springframework.web.reactive.socket.server.WebSocketService;
+import org.springframework.web.server.ServerWebExchange;
+
+/**
+ * {@code HandlerAdapter} that allows using a {@link WebSocketHandler} contract
+ * with the generic {@link DispatcherHandler} mapping URLs directly to such
+ * handlers. Requests are handled through the configured {@link WebSocketService}.
+ *
+ * @author Rossen Stoyanchev
+ * @since 5.0
+ */
+public class WebSocketHandlerAdapter implements HandlerAdapter {
+
+	private final WebSocketService webSocketService;
+
+
+	/**
+	 * Default constructor that creates and uses a
+	 * {@link HandshakeWebSocketService} for a straight-up WebSocket interaction,
+	 * i.e. treating incoming requests as WebSocket handshake requests.
+	 */
+	public WebSocketHandlerAdapter() {
+		this(new HandshakeWebSocketService());
+	}
+
+	/**
+	 * Alternative constructor with the {@link WebSocketService} to use.
+	 */
+	public WebSocketHandlerAdapter(WebSocketService webSocketService) {
+		Assert.notNull(webSocketService, "'webSocketService' is required");
+		this.webSocketService = webSocketService;
+	}
+
+
+	public WebSocketService getWebSocketService() {
+		return this.webSocketService;
+	}
+
+
+	@Override
+	public boolean supports(Object handler) {
+		return WebSocketHandler.class.isAssignableFrom(handler.getClass());
+	}
+
+	@Override
+	public Mono<HandlerResult> handle(ServerWebExchange exchange, Object handler) {
+		WebSocketHandler webSocketHandler = (WebSocketHandler) handler;
+		return getWebSocketService().handleRequest(exchange, webSocketHandler).then(Mono.empty());
+	}
+
+}

spring-web-reactive/src/main/java/org/springframework/web/reactive/socket/server/support/package-info.java

@@ -0,0 +1,4 @@
+/**
+ * Server-side support classes for WebSocket requests.
+ */
+package org.springframework.web.reactive.socket.server.support;

spring-web-reactive/src/main/java/org/springframework/web/reactive/socket/server/upgrade/RxNettyRequestUpgradeStrategy.java

@@ -0,0 +1,61 @@
+/*
+ * Copyright 2002-2016 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.web.reactive.socket.server.upgrade;
+
+import java.util.List;
+import java.util.Map;
+
+import reactor.core.publisher.Mono;
+import rx.Observable;
+import rx.RxReactiveStreams;
+
+import org.springframework.http.server.reactive.RxNettyServerHttpRequest;
+import org.springframework.http.server.reactive.RxNettyServerHttpResponse;
+import org.springframework.web.reactive.socket.WebSocketHandler;
+import org.springframework.web.reactive.socket.adapter.RxNettyWebSocketHandlerAdapter;
+import org.springframework.web.reactive.socket.server.RequestUpgradeStrategy;
+import org.springframework.web.server.ServerWebExchange;
+
+/**
+ * A {@link RequestUpgradeStrategy} for use with RxNetty.
+ *
+ * @author Rossen Stoyanchev
+ * @since 5.0
+ */
+public class RxNettyRequestUpgradeStrategy implements RequestUpgradeStrategy {
+
+	@Override
+	public Mono<Void> upgrade(ServerWebExchange exchange, WebSocketHandler webSocketHandler) {
+
+		RxNettyServerHttpRequest request = (RxNettyServerHttpRequest) exchange.getRequest();
+		RxNettyServerHttpResponse response = (RxNettyServerHttpResponse) exchange.getResponse();
+
+		RxNettyWebSocketHandlerAdapter rxNettyHandler =
+				new RxNettyWebSocketHandlerAdapter(request, response, webSocketHandler);
+
+		Observable<Void> completion = response.getRxNettyResponse()
+				.acceptWebSocketUpgrade(rxNettyHandler)
+				.subprotocol(getSubProtocols(webSocketHandler));
+
+		return Mono.from(RxReactiveStreams.toPublisher(completion));
+	}
+
+	private static String[] getSubProtocols(WebSocketHandler webSocketHandler) {
+		List<String> subProtocols = webSocketHandler.getSubProtocols();
+		return subProtocols.toArray(new String[subProtocols.size()]);
+	}
+
+}

spring-web-reactive/src/main/java/org/springframework/web/reactive/socket/server/upgrade/package-info.java

@@ -0,0 +1,5 @@
+/**
+ * Holds implementations of
+ * {@link org.springframework.web.reactive.socket.server.RequestUpgradeStrategy}.
+ */
+package org.springframework.web.reactive.socket.server.upgrade;

spring-web-reactive/src/test/java/org/springframework/web/reactive/socket/server/AbstractWebSocketHandlerIntegrationTests.java

@@ -0,0 +1,122 @@
+/*
+ * Copyright 2002-2016 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.web.reactive.socket.server;
+
+import org.junit.After;
+import org.junit.Before;
+import org.junit.runner.RunWith;
+import org.junit.runners.Parameterized;
+import org.junit.runners.Parameterized.Parameter;
+import org.junit.runners.Parameterized.Parameters;
+
+import org.springframework.context.annotation.AnnotationConfigApplicationContext;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.http.server.reactive.HttpHandler;
+import org.springframework.http.server.reactive.bootstrap.HttpServer;
+import org.springframework.http.server.reactive.bootstrap.RxNettyHttpServer;
+import org.springframework.util.SocketUtils;
+import org.springframework.web.reactive.DispatcherHandler;
+import org.springframework.web.reactive.socket.server.support.HandshakeWebSocketService;
+import org.springframework.web.reactive.socket.server.support.WebSocketHandlerAdapter;
+import org.springframework.web.reactive.socket.server.upgrade.RxNettyRequestUpgradeStrategy;
+
+/**
+ * Base class for WebSocket integration tests involving a server-side
+ * {@code WebSocketHandler}. Sub-classes to return a Spring configuration class
+ * via {@link #getWebConfigClass()} containing a SimpleUrlHandlerMapping with
+ * pattern-to-WebSocketHandler mappings.
+ *
+ * @author Rossen Stoyanchev
+ */
+@RunWith(Parameterized.class)
+@SuppressWarnings({"unused", "WeakerAccess"})
+public abstract class AbstractWebSocketHandlerIntegrationTests {
+
+	protected int port;
+
+	@Parameter(0)
+	public HttpServer server;
+
+	@Parameter(1)
+	public Class<?> handlerAdapterConfigClass;
+
+
+	@Parameters
+	public static Object[][] arguments() {
+		return new Object[][] {
+				{new RxNettyHttpServer(), RxNettyConfig.class}
+		};
+	}
+
+
+	@Before
+	public void setup() throws Exception {
+		this.port = SocketUtils.findAvailableTcpPort();
+		this.server.setPort(this.port);
+		this.server.setHandler(createHttpHandler());
+		this.server.afterPropertiesSet();
+		this.server.start();
+	}
+
+	private HttpHandler createHttpHandler() {
+		AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext();
+		context.register(DispatcherConfig.class, this.handlerAdapterConfigClass);
+		context.register(getWebConfigClass());
+		context.refresh();
+		return DispatcherHandler.toHttpHandler(context);
+	}
+
+	protected abstract Class<?> getWebConfigClass();
+
+	@After
+	public void tearDown() throws Exception {
+		this.server.stop();
+	}
+
+
+	@Configuration
+	static class DispatcherConfig {
+
+		@Bean
+		public DispatcherHandler webHandler() {
+			return new DispatcherHandler();
+		}
+	}
+
+	static abstract class AbstractHandlerAdapterConfig {
+
+		@Bean
+		public WebSocketHandlerAdapter handlerAdapter() {
+			RequestUpgradeStrategy strategy = createUpgradeStrategy();
+			WebSocketService service = new HandshakeWebSocketService(strategy);
+			return new WebSocketHandlerAdapter(service);
+		}
+
+		protected abstract RequestUpgradeStrategy createUpgradeStrategy();
+
+	}
+
+	@Configuration
+	static class RxNettyConfig extends AbstractHandlerAdapterConfig {
+
+		@Override
+		protected RequestUpgradeStrategy createUpgradeStrategy() {
+			return new RxNettyRequestUpgradeStrategy();
+		}
+	}
+
+}

spring-web-reactive/src/test/java/org/springframework/web/reactive/socket/server/BasicWebSocketHandlerIntegrationTests.java

@@ -0,0 +1,101 @@
+/*
+ * Copyright 2002-2016 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.web.reactive.socket.server;
+
+import java.nio.charset.StandardCharsets;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+import io.netty.handler.codec.http.websocketx.CloseWebSocketFrame;
+import io.netty.handler.codec.http.websocketx.TextWebSocketFrame;
+import io.netty.handler.codec.http.websocketx.WebSocketFrame;
+import io.reactivex.netty.protocol.http.client.HttpClient;
+import io.reactivex.netty.protocol.http.ws.client.WebSocketResponse;
+import org.junit.Test;
+import reactor.core.publisher.Mono;
+import rx.Observable;
+
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.web.reactive.HandlerMapping;
+import org.springframework.web.reactive.handler.SimpleUrlHandlerMapping;
+import org.springframework.web.reactive.socket.WebSocketHandler;
+import org.springframework.web.reactive.socket.WebSocketSession;
+
+import static org.junit.Assert.assertEquals;
+
+/**
+ * Basic WebSocket integration
+ * @author Rossen Stoyanchev
+ */
+@SuppressWarnings({"unused", "WeakerAccess"})
+public class BasicWebSocketHandlerIntegrationTests extends AbstractWebSocketHandlerIntegrationTests {
+
+
+	@Override
+	protected Class<?> getWebConfigClass() {
+		return WebConfig.class;
+	}
+
+
+	@Test
+	public void echo() throws Exception {
+		Observable<String> messages = Observable.range(1, 10).map(i -> "Interval " + i);
+		List<String> actual = HttpClient.newClient("localhost", this.port)
+				.createGet("/echo")
+				.requestWebSocketUpgrade()
+				.flatMap(WebSocketResponse::getWebSocketConnection)
+				.flatMap(conn -> conn.write(messages
+						.map(TextWebSocketFrame::new)
+						.cast(WebSocketFrame.class)
+						.concatWith(Observable.just(new CloseWebSocketFrame())))
+						.cast(WebSocketFrame.class)
+						.mergeWith(conn.getInput())
+				)
+				.take(10)
+				.map(frame -> frame.content().toString(StandardCharsets.UTF_8))
+				.toList().toBlocking().first();
+		List<String> expected = messages.toList().toBlocking().first();
+		assertEquals(expected, actual);
+	}
+
+
+	@Configuration
+	static class WebConfig {
+
+		@Bean
+		public HandlerMapping handlerMapping() {
+
+			Map<String, WebSocketHandler> map = new HashMap<>();
+			map.put("/echo", new EchoWebSocketHandler());
+
+			SimpleUrlHandlerMapping mapping = new SimpleUrlHandlerMapping();
+			mapping.setUrlMap(map);
+			return mapping;
+		}
+
+	}
+
+	private static class EchoWebSocketHandler implements WebSocketHandler {
+
+		@Override
+		public Mono<Void> handle(WebSocketSession session) {
+			return session.send(session.receive());
+		}
+	}
+
+}