/*
* Copyright 2014 Jeanfrancois Arcand
*
* 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.atmosphere.interceptor;
import org.atmosphere.client.TrackMessageSizeFilter;
import org.atmosphere.cpr.Action;
import org.atmosphere.cpr.ApplicationConfig;
import org.atmosphere.cpr.AtmosphereConfig;
import org.atmosphere.cpr.AtmosphereFramework;
import org.atmosphere.cpr.AtmosphereInterceptor;
import org.atmosphere.cpr.AtmosphereInterceptorAdapter;
import org.atmosphere.cpr.AtmosphereRequest;
import org.atmosphere.cpr.AtmosphereResource;
import org.atmosphere.cpr.AtmosphereResourceEvent;
import org.atmosphere.cpr.AtmosphereResourceImpl;
import org.atmosphere.cpr.AtmosphereResponse;
import org.atmosphere.cpr.BroadcastFilter;
import org.atmosphere.cpr.HeaderConfig;
import org.atmosphere.util.Utils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.io.IOException;
import java.util.concurrent.atomic.AtomicReference;
import static org.atmosphere.cpr.AtmosphereResourceEventListenerAdapter.OnSuspend;
import static org.atmosphere.cpr.FrameworkConfig.CALLBACK_JAVASCRIPT_PROTOCOL;
import static org.atmosphere.cpr.HeaderConfig.X_ATMOSPHERE_ERROR;
/**
* <p>
* An Interceptor that send back to a websocket and http client the value of {@link HeaderConfig#X_ATMOSPHERE_TRACKING_ID}.
* </p>
* <p/>
* <p>
* Moreover, if any {@link HeartbeatInterceptor} is installed, it provides the configured heartbeat interval in seconds
* and the value to be sent for each heartbeat by the client. If not interceptor is installed, then "0" is sent to tell
* he client to not send any heartbeat.
* </p>
*
* @author Jeanfrancois Arcand
*/
public class JavaScriptProtocol extends AtmosphereInterceptorAdapter {
private final static Logger logger = LoggerFactory.getLogger(JavaScriptProtocol.class);
private String wsDelimiter = "|";
private final TrackMessageSizeFilter f = new TrackMessageSizeFilter();
private AtmosphereFramework framework;
private boolean enforceAtmosphereVersion = true;
@Override
public void configure(final AtmosphereConfig config) {
String s = config.getInitParameter(ApplicationConfig.MESSAGE_DELIMITER);
if (s != null) {
wsDelimiter = s;
}
enforceAtmosphereVersion = Boolean.valueOf(config.getInitParameter(ApplicationConfig.ENFORCE_ATMOSPHERE_VERSION, "true"));
framework = config.framework();
}
@Override
public Action inspect(final AtmosphereResource ar) {
if (Utils.webSocketMessage(ar)) return Action.CONTINUE;
final AtmosphereResourceImpl r = AtmosphereResourceImpl.class.cast(ar);
final AtmosphereRequest request = r.getRequest(false);
final AtmosphereResponse response = r.getResponse(false);
String uuid = request.getHeader(HeaderConfig.X_ATMOSPHERE_TRACKING_ID);
String handshakeUUID = request.getHeader(HeaderConfig.X_ATMO_PROTOCOL);
if (uuid != null && uuid.equals("0") && handshakeUUID != null) {
if (enforceAtmosphereVersion) {
String javascriptVersion = request.getHeader(HeaderConfig.X_ATMOSPHERE_FRAMEWORK);
int version = parseVersion(javascriptVersion.split("-")[0]);
if (version < 221) {
logger.error("Invalid Atmosphere Version {}", javascriptVersion);
response.setStatus(501);
response.addHeader(X_ATMOSPHERE_ERROR, "Atmosphere Protocol version not supported.");
try {
response.flushBuffer();
} catch (IOException e) {
}
return Action.CANCELLED;
}
}
request.header(HeaderConfig.X_ATMO_PROTOCOL, null);
// Extract heartbeat data
int heartbeatInterval = 0;
String heartbeatData = "";
for (final AtmosphereInterceptor interceptor : framework.interceptors()) {
if (HeartbeatInterceptor.class.isAssignableFrom(interceptor.getClass())) {
final HeartbeatInterceptor heartbeatInterceptor = HeartbeatInterceptor.class.cast(interceptor);
heartbeatInterval = heartbeatInterceptor.clientHeartbeatFrequencyInSeconds() * 1000;
heartbeatData = new String(heartbeatInterceptor.getPaddingBytes());
break;
}
}
// Since 1.0.10
final StringBuffer message = new StringBuffer(r.uuid()).append(wsDelimiter);
// since 2.2
if (enforceAtmosphereVersion) {
message.append(heartbeatInterval)
.append(wsDelimiter)
.append(heartbeatData)
.append(wsDelimiter);
}
// https://github.com/Atmosphere/atmosphere/issues/993
final AtomicReference<String> protocolMessage = new AtomicReference<String>(message.toString());
if (r.getBroadcaster().getBroadcasterConfig().hasFilters()) {
for (BroadcastFilter bf : r.getBroadcaster().getBroadcasterConfig().filters()) {
if (TrackMessageSizeFilter.class.isAssignableFrom(bf.getClass())) {
protocolMessage.set((String) f.filter(r.getBroadcaster().getID(), r, protocolMessage.get(), protocolMessage.get()).message());
break;
}
}
}
if (!Utils.resumableTransport(r.transport())) {
OnSuspend a = new OnSuspend() {
@Override
public void onSuspend(AtmosphereResourceEvent event) {
response.write(protocolMessage.get());
try {
response.flushBuffer();
} catch (IOException e) {
logger.trace("", e);
}
r.removeEventListener(this);
}
};
// Pass the information to Servlet Based Framework
request.setAttribute(CALLBACK_JAVASCRIPT_PROTOCOL, a);
r.addEventListener(a);
} else {
response.write(protocolMessage.get());
}
// We don't need to reconnect here
if (r.transport() == AtmosphereResource.TRANSPORT.WEBSOCKET
|| r.transport() == AtmosphereResource.TRANSPORT.STREAMING
|| r.transport() == AtmosphereResource.TRANSPORT.SSE) {
return Action.CONTINUE;
} else {
return Action.CANCELLED;
}
}
return Action.CONTINUE;
}
private static int parseVersion(String version) {
// Remove any qualifier if the version is 1.2.3.qualifier
String[] parts = version.split("\\.");
return Integer.valueOf(parts[0] + parts[1] + parts[2]);
}
public String wsDelimiter() {
return wsDelimiter;
}
public JavaScriptProtocol wsDelimiter(String wsDelimiter) {
this.wsDelimiter = wsDelimiter;
return this;
}
public boolean enforceAtmosphereVersion(){
return enforceAtmosphereVersion;
}
public JavaScriptProtocol enforceAtmosphereVersion(boolean enforceAtmosphereVersion) {
this.enforceAtmosphereVersion = enforceAtmosphereVersion;
return this;
}
@Override
public String toString() {
return "Atmosphere JavaScript Protocol";
}
}