Polish SockJsClient

This commit is contained in:
Rossen Stoyanchev 2014-07-30 15:29:46 -04:00
parent ba952ca331
commit c68b4c01e1
6 changed files with 113 additions and 53 deletions

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@ -29,8 +29,11 @@ import org.springframework.web.socket.TextMessage;
import org.springframework.web.socket.WebSocketHandler;
import org.springframework.web.socket.WebSocketSession;
import org.springframework.web.socket.sockjs.frame.SockJsFrame;
import org.springframework.web.socket.sockjs.transport.TransportType;
import java.net.URI;
import java.util.Arrays;
import java.util.List;
/**
* Abstract base class for XHR transport implementations to extend.
@ -59,17 +62,32 @@ public abstract class AbstractXhrTransport implements XhrTransport {
private HttpHeaders xhrSendRequestHeaders = new HttpHeaders();
@Override
public List<TransportType> getTransportTypes() {
return (isXhrStreamingDisabled() ?
Arrays.asList(TransportType.XHR) :
Arrays.asList(TransportType.XHR_STREAMING, TransportType.XHR));
}
/**
* Whether to attempt to connect with "xhr_streaming" first before trying
* with "xhr" next, see {@link XhrTransport#isXhrStreamingDisabled()}.
* An {@code XhrTransport} can support both the "xhr_streaming" and "xhr"
* SockJS server transports. From a client perspective there is no
* implementation difference.
*
* <p>Typically an {@code XhrTransport} is used as "XHR streaming" first and
* then, if that fails, as "XHR". In some cases however it may be helpful to
* suppress XHR streaming so that only XHR is attempted.
*
* <p>By default this property is set to {@code false} which means both
* "xhr_streaming" and "xhr" will be tried.
* "XHR streaming" and "XHR" apply.
*/
public void setXhrStreamingDisabled(boolean disabled) {
this.xhrStreamingDisabled = disabled;
}
/**
* Whether XHR streaming is disabled or not.
*/
public boolean isXhrStreamingDisabled() {
return this.xhrStreamingDisabled;
}

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@ -43,7 +43,11 @@ import java.util.concurrent.ConcurrentHashMap;
/**
* A SockJS implementation of
* {@link org.springframework.web.socket.client.WebSocketClient WebSocketClient}
* with HTTP-based fallback alternative simulating a WebSocket interaction.
* with fallback alternatives that simulate a WebSocket interaction through plain
* HTTP streaming and long polling techniques..
*
* <p>Implements {@link Lifecycle} in order to propagate lifecycle events to
* the transports it is configured with.
*
* @author Rossen Stoyanchev
* @since 4.1
@ -59,27 +63,33 @@ public class SockJsClient extends AbstractWebSocketClient implements Lifecycle {
private static final Log logger = LogFactory.getLog(SockJsClient.class);
private final List<Transport> transports;
private InfoReceiver infoReceiver;
private final List<Transport> transports;
private SockJsMessageCodec messageCodec;
private TaskScheduler taskScheduler;
private TaskScheduler connectTimeoutScheduler;
private final Map<URI, ServerInfo> infoCache = new ConcurrentHashMap<URI, ServerInfo>();
private final Map<URI, ServerInfo> serverInfoCache = new ConcurrentHashMap<URI, ServerInfo>();
private volatile boolean running = false;
/**
* Create a {@code SockJsClient} with the given transports.
* @param transports the transports to use
*
* <p>If the list includes an {@link XhrTransport} (or more specifically an
* implementation of {@link InfoReceiver}) the instance is used to initialize
* the {@link #setInfoReceiver(InfoReceiver) infoReceiver} property, or
* otherwise is defaulted to {@link RestTemplateXhrTransport}.
*
* @param transports the (non-empty) list of transports to use
*/
public SockJsClient(List<Transport> transports) {
Assert.notEmpty(transports, "No transports provided");
this.transports = new ArrayList<Transport>(transports);
this.infoReceiver = initInfoReceiver(transports);
this.transports = new ArrayList<Transport>(transports);
if (jackson2Present) {
this.messageCodec = new Jackson2SockJsMessageCodec();
}
@ -99,16 +109,21 @@ public class SockJsClient extends AbstractWebSocketClient implements Lifecycle {
* Configure the {@code InfoReceiver} to use to perform the SockJS "Info"
* request before the SockJS session starts.
*
* <p>By default this is initialized either by looking through the configured
* transports to find the first {@code XhrTransport} or by creating an
* instance of {@code RestTemplateXhrTransport}.
* <p>If the list of transports provided to the constructor contained an
* {@link XhrTransport} or an implementation of {@link InfoReceiver} that
* instance would have been used to initialize this property, or otherwise
* it defaults to {@link RestTemplateXhrTransport}.
*
* @param infoReceiver the transport to use for the SockJS "Info" request
*/
public void setInfoReceiver(InfoReceiver infoReceiver) {
Assert.notNull(infoReceiver, "'infoReceiver' is required");
this.infoReceiver = infoReceiver;
}
/**
* Return the configured {@code InfoReceiver}, never {@code null}.
*/
public InfoReceiver getInfoReceiver() {
return this.infoReceiver;
}
@ -133,22 +148,19 @@ public class SockJsClient extends AbstractWebSocketClient implements Lifecycle {
/**
* Configure a {@code TaskScheduler} for scheduling a connect timeout task
* where the timeout value is calculated based on the duration of the initial
* SockJS info request. Having a connect timeout task is optional but can
* improve the speed with which the client falls back to alternative
* transport options.
*
* <p>By default no task scheduler is configured in which case it may take
* longer before a fallback transport can be used.
*
* @param taskScheduler the scheduler to use
* SockJS "Info" request. The connect timeout task ensures a more timely
* fallback but is otherwise entirely optional.
* <p>By default this is not configured in which case a fallback may take longer.
* @param connectTimeoutScheduler the task scheduler to use
*/
public void setTaskScheduler(TaskScheduler taskScheduler) {
this.taskScheduler = taskScheduler;
public void setConnectTimeoutScheduler(TaskScheduler connectTimeoutScheduler) {
this.connectTimeoutScheduler = connectTimeoutScheduler;
}
@Override
public void start() {
if (!isRunning()) {
this.running = true;
for (Transport transport : this.transports) {
if (transport instanceof Lifecycle) {
if (!((Lifecycle) transport).isRunning()) {
@ -162,6 +174,7 @@ public class SockJsClient extends AbstractWebSocketClient implements Lifecycle {
@Override
public void stop() {
if (!isRunning()) {
this.running = false;
for (Transport transport : this.transports) {
if (transport instanceof Lifecycle) {
if (((Lifecycle) transport).isRunning()) {
@ -177,8 +190,14 @@ public class SockJsClient extends AbstractWebSocketClient implements Lifecycle {
return this.running;
}
/**
* By default the result of a SockJS "Info" request, including whether the
* server has WebSocket disabled and how long the request took (used for
* calculating transport timeout time) is cached. This method can be used to
* clear that cache hence causing it to re-populate.
*/
public void clearServerInfoCache() {
this.infoCache.clear();
this.serverInfoCache.clear();
}
@Override
@ -198,7 +217,7 @@ public class SockJsClient extends AbstractWebSocketClient implements Lifecycle {
try {
SockJsUrlInfo sockJsUrlInfo = new SockJsUrlInfo(url);
ServerInfo serverInfo = getServerInfo(sockJsUrlInfo);
createFallbackChain(sockJsUrlInfo, handshakeHeaders, serverInfo).connect(handler, connectFuture);
createRequest(sockJsUrlInfo, handshakeHeaders, serverInfo).connect(handler, connectFuture);
}
catch (Throwable exception) {
if (logger.isErrorEnabled()) {
@ -211,52 +230,39 @@ public class SockJsClient extends AbstractWebSocketClient implements Lifecycle {
private ServerInfo getServerInfo(SockJsUrlInfo sockJsUrlInfo) {
URI infoUrl = sockJsUrlInfo.getInfoUrl();
ServerInfo info = this.infoCache.get(infoUrl);
ServerInfo info = this.serverInfoCache.get(infoUrl);
if (info == null) {
long start = System.currentTimeMillis();
String response = this.infoReceiver.executeInfoRequest(infoUrl);
long infoRequestTime = System.currentTimeMillis() - start;
info = new ServerInfo(response, infoRequestTime);
this.infoCache.put(infoUrl, info);
this.serverInfoCache.put(infoUrl, info);
}
return info;
}
private DefaultTransportRequest createFallbackChain(SockJsUrlInfo urlInfo, HttpHeaders headers, ServerInfo serverInfo) {
private DefaultTransportRequest createRequest(SockJsUrlInfo urlInfo, HttpHeaders headers, ServerInfo serverInfo) {
List<DefaultTransportRequest> requests = new ArrayList<DefaultTransportRequest>(this.transports.size());
for (Transport transport : this.transports) {
if (transport instanceof XhrTransport) {
XhrTransport xhrTransport = (XhrTransport) transport;
if (!xhrTransport.isXhrStreamingDisabled()) {
addRequest(requests, urlInfo, headers, serverInfo, transport, TransportType.XHR_STREAMING);
for (TransportType type : transport.getTransportTypes()) {
if (serverInfo.isWebSocketEnabled() || !TransportType.WEBSOCKET.equals(type)) {
requests.add(new DefaultTransportRequest(urlInfo, headers, transport, type, getMessageCodec()));
}
addRequest(requests, urlInfo, headers, serverInfo, transport, TransportType.XHR);
}
else if (serverInfo.isWebSocketEnabled()) {
addRequest(requests, urlInfo, headers, serverInfo, transport, TransportType.WEBSOCKET);
}
}
Assert.notEmpty(requests,
"0 transports for request to " + urlInfo + " . Configured transports: " +
this.transports + ". SockJS server webSocketEnabled=" + serverInfo.isWebSocketEnabled());
Assert.notEmpty(requests, "No transports, " + urlInfo + ", wsEnabled=" + serverInfo.isWebSocketEnabled());
for (int i = 0; i < requests.size() - 1; i++) {
requests.get(i).setFallbackRequest(requests.get(i + 1));
DefaultTransportRequest request = requests.get(i);
request.setUser(getUser());
if (this.connectTimeoutScheduler != null) {
request.setTimeoutValue(serverInfo.getRetransmissionTimeout());
request.setTimeoutScheduler(this.connectTimeoutScheduler);
}
request.setFallbackRequest(requests.get(i + 1));
}
return requests.get(0);
}
private void addRequest(List<DefaultTransportRequest> requests, SockJsUrlInfo info, HttpHeaders headers,
ServerInfo serverInfo, Transport transport, TransportType type) {
DefaultTransportRequest request = new DefaultTransportRequest(info, headers, transport, type, getMessageCodec());
request.setUser(getUser());
if (this.taskScheduler != null) {
request.setTimeoutValue(serverInfo.getRetransmissionTimeout());
request.setTimeoutScheduler(this.taskScheduler);
}
requests.add(request);
}
/**
* Return the user to associate with the SockJS session and make available via
* {@link org.springframework.web.socket.WebSocketSession#getPrincipal()
@ -269,6 +275,9 @@ public class SockJsClient extends AbstractWebSocketClient implements Lifecycle {
}
/**
* A simple value object holding the result from a SockJS "Info" request.
*/
private static class ServerInfo {
private final boolean webSocketEnabled;

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@ -19,6 +19,9 @@ package org.springframework.web.socket.sockjs.client;
import org.springframework.util.concurrent.ListenableFuture;
import org.springframework.web.socket.WebSocketHandler;
import org.springframework.web.socket.WebSocketSession;
import org.springframework.web.socket.sockjs.transport.TransportType;
import java.util.List;
/**
* A client-side implementation for a SockJS transport.
@ -28,6 +31,13 @@ import org.springframework.web.socket.WebSocketSession;
*/
public interface Transport {
/**
* Return the SockJS transport types that this transport can be used for.
* In particular since from a client perspective there is no difference
* between XHR and XHR streaming, an {@code XhrTransport} could do both.
*/
List<TransportType> getTransportTypes();
/**
* Connect the transport.
*

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@ -30,8 +30,11 @@ import org.springframework.web.socket.WebSocketHttpHeaders;
import org.springframework.web.socket.WebSocketSession;
import org.springframework.web.socket.client.WebSocketClient;
import org.springframework.web.socket.handler.TextWebSocketHandler;
import org.springframework.web.socket.sockjs.transport.TransportType;
import java.net.URI;
import java.util.Arrays;
import java.util.List;
import java.util.concurrent.atomic.AtomicInteger;
/**
@ -56,6 +59,11 @@ public class WebSocketTransport implements Transport, Lifecycle {
}
@Override
public List<TransportType> getTransportTypes() {
return Arrays.asList(TransportType.WEBSOCKET);
}
/**
* Return the configured {@code WebSocketClient}.
*/

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@ -218,7 +218,7 @@ public abstract class AbstractSockJsIntegrationTests {
this.errorFilter.sleepDelayMap.put("/xhr_streaming", 10000L);
this.errorFilter.responseStatusMap.put("/xhr_streaming", 503);
initSockJsClient(createXhrTransport());
this.sockJsClient.setTaskScheduler(this.wac.getBean(ThreadPoolTaskScheduler.class));
this.sockJsClient.setConnectTimeoutScheduler(this.wac.getBean(ThreadPoolTaskScheduler.class));
WebSocketSession clientSession = sockJsClient.doHandshake(clientHandler, this.baseUrl + "/echo").get();
assertEquals("Fallback didn't occur", XhrClientSockJsSession.class, clientSession.getClass());
TextMessage message = new TextMessage("message1");

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@ -22,8 +22,11 @@ import org.springframework.util.concurrent.ListenableFutureCallback;
import org.springframework.web.socket.TextMessage;
import org.springframework.web.socket.WebSocketHandler;
import org.springframework.web.socket.WebSocketSession;
import org.springframework.web.socket.sockjs.transport.TransportType;
import java.net.URI;
import java.util.Arrays;
import java.util.List;
import static org.mockito.Mockito.mock;
import static org.mockito.Mockito.verify;
@ -46,6 +49,11 @@ class TestTransport implements Transport {
this.name = name;
}
@Override
public List<TransportType> getTransportTypes() {
return Arrays.asList(TransportType.WEBSOCKET);
}
public TransportRequest getRequest() {
return this.request;
}
@ -84,6 +92,13 @@ class TestTransport implements Transport {
super(name);
}
@Override
public List<TransportType> getTransportTypes() {
return (isXhrStreamingDisabled() ?
Arrays.asList(TransportType.XHR) :
Arrays.asList(TransportType.XHR_STREAMING, TransportType.XHR));
}
public void setStreamingDisabled(boolean streamingDisabled) {
this.streamingDisabled = streamingDisabled;
}