/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.apache.brooklyn.policy.ha;
import org.apache.brooklyn.api.entity.EntityLocal;
import org.apache.brooklyn.api.policy.Policy;
import org.apache.brooklyn.api.sensor.Sensor;
import org.apache.brooklyn.api.sensor.SensorEvent;
import org.apache.brooklyn.api.sensor.SensorEventListener;
import org.apache.brooklyn.config.ConfigKey;
import org.apache.brooklyn.core.config.ConfigKeys;
import org.apache.brooklyn.core.policy.AbstractPolicy;
import org.apache.brooklyn.util.core.flags.SetFromFlag;
import org.apache.brooklyn.util.javalang.JavaClassNames;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.google.common.base.Preconditions;
public class ConditionalSuspendPolicy extends AbstractPolicy {
private static final Logger LOG = LoggerFactory.getLogger(ConditionalSuspendPolicy.class);
@SetFromFlag("suppressSensor")
@SuppressWarnings({ "rawtypes", "unchecked" })
public static final ConfigKey<Sensor<?>> SUSPEND_SENSOR = (ConfigKey) ConfigKeys.newConfigKey(Sensor.class,
"suppressSensor", "Sensor which will suppress the target policy", HASensors.CONNECTION_FAILED);
@SetFromFlag("resetSensor")
@SuppressWarnings({ "rawtypes", "unchecked" })
public static final ConfigKey<Sensor<?>> RESUME_SENSOR = (ConfigKey) ConfigKeys.newConfigKey(Sensor.class,
"resetSensor", "Resume target policy when this sensor is observed", HASensors.CONNECTION_RECOVERED);
@SetFromFlag("target")
public static final ConfigKey<Object> SUSPEND_TARGET = ConfigKeys.newConfigKey(Object.class,
"target", "The target policy to suspend. Either direct reference or the value of the suspendTarget config on a policy from the same entity.");
@Override
public void setEntity(EntityLocal entity) {
super.setEntity(entity);
Object target = config().get(SUSPEND_TARGET);
Preconditions.checkNotNull(target, "Suspend target required");
Preconditions.checkNotNull(getTargetPolicy(), "Can't find target policy set in " + SUSPEND_TARGET.getName() + ": " + target);
subscribe();
uniqueTag = JavaClassNames.simpleClassName(getClass())+":"+getConfig(SUSPEND_SENSOR).getName()+":"+getConfig(RESUME_SENSOR).getName();
}
private void subscribe() {
subscriptions().subscribe(entity, getConfig(SUSPEND_SENSOR), new SensorEventListener<Object>() {
@Override public void onEvent(final SensorEvent<Object> event) {
if (isRunning()) {
Policy target = getTargetPolicy();
target.suspend();
LOG.debug("Suspended policy " + target + ", triggered by " + event.getSensor() + " = " + event.getValue());
}
}
});
subscriptions().subscribe(entity, getConfig(RESUME_SENSOR), new SensorEventListener<Object>() {
@Override public void onEvent(final SensorEvent<Object> event) {
if (isRunning()) {
Policy target = getTargetPolicy();
target.resume();
LOG.debug("Resumed policy " + target + ", triggered by " + event.getSensor() + " = " + event.getValue());
}
}
});
}
private Policy getTargetPolicy() {
Object target = config().get(SUSPEND_TARGET);
if (target instanceof Policy) {
return (Policy)target;
} else if (target instanceof String) {
for (Policy policy : entity.policies()) {
// No way to set config values for keys NOT declared in the policy,
// so must use displayName as a generally available config value.
if (target.equals(policy.getDisplayName()) || target.equals(policy.getClass().getName())) {
return policy;
}
}
} else {
throw new IllegalStateException("Unexpected type " + target.getClass() + " for target " + target);
}
return null;
}
}