/*
* 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.container;
import org.atmosphere.cpr.Action;
import org.atmosphere.cpr.ApplicationConfig;
import org.atmosphere.cpr.AsyncSupport;
import org.atmosphere.cpr.AsynchronousProcessor;
import org.atmosphere.cpr.AtmosphereConfig;
import org.atmosphere.cpr.AtmosphereRequest;
import org.atmosphere.cpr.AtmosphereResource;
import org.atmosphere.cpr.AtmosphereResourceImpl;
import org.atmosphere.cpr.AtmosphereResponse;
import org.jboss.servlet.http.HttpEvent;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import javax.servlet.ServletException;
import java.io.IOException;
import static org.atmosphere.cpr.ApplicationConfig.MAX_INACTIVE;
/**
* Comet Portable Runtime implementation on top of Tomcat AIO.
*
* @author Jeanfrancois Arcand
*/
public class JBossWebCometSupport extends AsynchronousProcessor {
private static final Logger logger = LoggerFactory.getLogger(JBossWebCometSupport.class);
public static final String HTTP_EVENT = "HttpEvent";
private final static String SUSPENDED = JBossWebCometSupport.class.getName() + ".suspended";
private static final IllegalStateException unableToDetectComet = new IllegalStateException(unableToDetectComet());
private final Boolean closeConnectionOnInputStream;
public JBossWebCometSupport(AtmosphereConfig config) {
super(config);
Object b = config.getInitParameter(ApplicationConfig.TOMCAT_CLOSE_STREAM) ;
closeConnectionOnInputStream = b == null ? true : Boolean.parseBoolean(b.toString());
try {
Class.forName(HttpEvent.class.getName());
} catch (Throwable e) {
throw new IllegalStateException(unableToDetectComet());
}
}
/**
* Invoked by the Tomcat AIO when a Comet request gets detected.
*
* @param req the {@link org.atmosphere.cpr.AtmosphereRequest}
* @param res the {@link org.atmosphere.cpr.AtmosphereResponse}
* @throws java.io.IOException
* @throws javax.servlet.ServletException
*/
public Action service(AtmosphereRequest req, AtmosphereResponse res) throws IOException, ServletException {
HttpEvent event = (HttpEvent) req.getAttribute(HTTP_EVENT);
// Comet is not enabled.
if (event == null) {
logger.error("HttpEvent is null, JBoss APR Not Properly installed");
throw unableToDetectComet;
}
if (logger.isTraceEnabled()) {
logger.trace("Event Type {} for {}", event.getType(), req.getRequestURL().toString());
}
Action action = null;
// For now, we are just interested in HttpEvent.REA
AtmosphereResource r = req.resource();
if (event.getType() == HttpEvent.EventType.BEGIN) {
action = suspended(req, res);
if (action.type() == Action.TYPE.SUSPEND) {
// Do nothing except setting the times out
try {
if (action.timeout() != -1) {
event.setTimeout((int) action.timeout());
} else {
event.setTimeout(Integer.MAX_VALUE);
}
req.setAttribute(SUSPENDED, true);
} catch (UnsupportedOperationException ex) {
// Swallow s Tomcat APR isn't supporting time out
// TODO: Must implement the same functionality using a Scheduler
}
} else if (action.type() == Action.TYPE.RESUME) {
event.close();
} else {
event.close();
}
} else if (event.getType() == HttpEvent.EventType.READ) {
// Not implemented
logger.debug("Receiving bytes, unable to process them.");
} else if (event.getType() == HttpEvent.EventType.EOF
|| event.getType() == HttpEvent.EventType.ERROR
|| event.getType() == HttpEvent.EventType.END) {
if (r != null && r.isResumed()) {
AtmosphereResourceImpl.class.cast(req.resource()).cancel();
} else if (req.getAttribute(SUSPENDED) != null && closeConnectionOnInputStream) {
req.setAttribute(SUSPENDED, null);
action = cancelled(req, res);
} else {
event.close();
}
} else if (event.getType() == HttpEvent.EventType.TIMEOUT) {
action = timedout(req, res);
event.close();
}
return action;
}
@Override
public Action cancelled(AtmosphereRequest req, AtmosphereResponse res) throws IOException, ServletException {
Action action = super.cancelled(req, res);
if (req.getAttribute(MAX_INACTIVE) != null && Long.class.cast(req.getAttribute(MAX_INACTIVE)) == -1) {
HttpEvent event = (HttpEvent) req.getAttribute(HTTP_EVENT);
if (event == null) {
return action;
}
event.close();
}
return action;
}
@Override
public void action(AtmosphereResourceImpl r) {
super.action(r);
if (r.action().type() == Action.TYPE.RESUME && r.isInScope()) {
complete(r);
}
}
@Override
public AsyncSupport complete(AtmosphereResourceImpl r) {
try {
HttpEvent event = (HttpEvent) r.getRequest(false).getAttribute(HTTP_EVENT);
// Resume without closing the underlying suspended connection.
if (event != null) {
event.close();
}
} catch (IOException ex) {
logger.debug("", ex);
}
return this;
}
/**
* Tomcat was unable to detect Atmosphere's CometProcessor implementation.
*
* @return an error message describing how to fix the issue.
*/
private static String unableToDetectComet() {
StringBuilder sb = new StringBuilder();
sb.append("JBoss failed to detect this is a Comet application because the APR Connector is not enabled. ");
sb.append("\nMake sure atmosphere-compat-jboss.jar is not under your WEB-INF/lib and ");
sb.append("You must use the atmosphere-native-runtime dependency in order to use native Comet Support");
sb.append("\nthere is no context.xml under WEB-INF");
return sb.toString();
}
}