/*
* 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.cpr.Action;
import org.atmosphere.cpr.AtmosphereConfig;
import org.atmosphere.cpr.AtmosphereInterceptor;
import org.atmosphere.cpr.AtmosphereResource;
import org.atmosphere.cpr.AtmosphereResourceEvent;
import org.atmosphere.cpr.AtmosphereResourceImpl;
import org.atmosphere.util.Utils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.io.IOException;
import java.util.concurrent.TimeUnit;
import static org.atmosphere.cpr.ApplicationConfig.ATMOSPHERERESOURCE_INTERCEPTOR_METHOD;
import static org.atmosphere.cpr.ApplicationConfig.ATMOSPHERERESOURCE_INTERCEPTOR_TIMEOUT;
import static org.atmosphere.cpr.AtmosphereResource.TRANSPORT.POLLING;
import static org.atmosphere.cpr.AtmosphereResource.TRANSPORT.UNDEFINED;
import static org.atmosphere.cpr.AtmosphereResourceEventListenerAdapter.OnBroadcast;
/**
* <p>This {@link AtmosphereInterceptor} implementation automatically suspends the intercepted
* {@link AtmosphereResource} and takes care of managing the response's state (flushing, resuming,
* etc.) when a {@link org.atmosphere.cpr.Broadcaster#broadcast} is invoked. When used, {@link org.atmosphere.cpr.AtmosphereHandler} implementations no longer need to make calls to
* {@link AtmosphereResource#suspend}.
* </p>
* If your application doesn't use {@link org.atmosphere.cpr.Broadcaster}, this interceptor will not work and you need to programmatically
* resume, flush, etc.
* <p/>
* <p>By default, intercepted {@link AtmosphereResource} instances are suspended when a GET
* request is received. You can change the triggering http method by configuring
* {@link org.atmosphere.cpr.ApplicationConfig#ATMOSPHERERESOURCE_INTERCEPTOR_METHOD}
* <p/>
* <p/>
* <p>Use this class when you don't want to manage the suspend/resume operation from your
* particular Atmosphere framework implementation classes ({@link org.atmosphere.cpr.AtmosphereHandler},
* {@link org.atmosphere.websocket.WebSocketHandler}, or
* {@link org.atmosphere.cpr.Meteor} instances) or extensions (GWT, Jersey, Wicket, etc...)
* </p>
* <strong>For this mechanism to work properly, each client must set the
* {@link org.atmosphere.cpr.HeaderConfig#X_ATMOSPHERE_TRANSPORT} header. Your AtmosphereHandler must also extends the
* {@link org.atmosphere.handler.AbstractReflectorAtmosphereHandler} or implements the logic defined inside
* {@link org.atmosphere.handler.AbstractReflectorAtmosphereHandler#postStateChange(org.atmosphere.cpr.AtmosphereResourceEvent)} </strong>
*
* @author Jeanfrancois Arcand
*/
public class AtmosphereResourceLifecycleInterceptor implements AtmosphereInterceptor {
private String method = "GET";
// For backward compat.
private Integer timeoutInSeconds = -1;
private static final Logger logger = LoggerFactory.getLogger(AtmosphereResourceLifecycleInterceptor.class);
private final boolean force;
private long timeoutInMilli = -1;
public AtmosphereResourceLifecycleInterceptor(){
this(false);
}
public AtmosphereResourceLifecycleInterceptor(boolean force){
this.force = force;
}
@Override
public void configure(AtmosphereConfig config) {
String s = config.getInitParameter(ATMOSPHERERESOURCE_INTERCEPTOR_METHOD);
if (s != null) {
method = s;
}
s = config.getInitParameter(ATMOSPHERERESOURCE_INTERCEPTOR_TIMEOUT);
if (s != null) {
timeoutInSeconds = Integer.valueOf(s);
timeoutInMilli = TimeUnit.MILLISECONDS.convert(timeoutInSeconds, TimeUnit.SECONDS);
}
}
public String method() {
return method;
}
public int timeoutInSeconds(){
return timeoutInSeconds;
}
public AtmosphereResourceLifecycleInterceptor method(String method){
this.method = method;
return this;
}
public AtmosphereResourceLifecycleInterceptor timeoutInSeconds(int timeoutInSeconds) {
this.timeoutInSeconds = timeoutInSeconds;
timeoutInMilli = TimeUnit.MILLISECONDS.convert(timeoutInSeconds, TimeUnit.SECONDS);
return this;
}
/**
* Automatically suspend the {@link AtmosphereResource} based on {@link AtmosphereResource.TRANSPORT} value.
*
* @param r a {@link AtmosphereResource}
* @return
*/
@Override
public Action inspect(AtmosphereResource r) {
switch (r.transport()) {
case JSONP:
case AJAX:
case LONG_POLLING:
r.resumeOnBroadcast(true);
break;
default:
break;
}
return Action.CONTINUE;
}
@Override
public void postInspect(final AtmosphereResource r) {
if (r.transport().equals(UNDEFINED) || Utils.webSocketMessage(r) || r.transport().equals(POLLING)) return;
AtmosphereResourceImpl impl = AtmosphereResourceImpl.class.cast(r);
if ( (force || impl.getRequest(false).getMethod().equalsIgnoreCase(method))
&& !impl.action().equals(Action.CANCELLED)
&& impl.isInScope()) {
logger.trace("Marking AtmosphereResource {} for suspend operation", r.uuid());
r.addEventListener(new OnBroadcast() {
@Override
public void onBroadcast(AtmosphereResourceEvent event) {
switch (r.transport()) {
case JSONP:
case AJAX:
case LONG_POLLING:
break;
default:
try {
r.getResponse().flushBuffer();
} catch (IOException e) {
logger.trace("", e);
}
break;
}
}
}).suspend(timeoutInMilli);
}
}
public String toString() {
return "Atmosphere LifeCycle";
}
}