/*
* 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.core.effector;
import java.util.Map;
import java.util.concurrent.Callable;
import java.util.concurrent.atomic.AtomicReference;
import org.apache.brooklyn.api.effector.Effector;
import org.apache.brooklyn.api.effector.ParameterType;
import org.apache.brooklyn.api.entity.Entity;
import org.apache.brooklyn.api.mgmt.Task;
import org.apache.brooklyn.api.mgmt.TaskAdaptable;
import org.apache.brooklyn.config.ConfigKey;
import org.apache.brooklyn.core.config.ConfigKeys;
import org.apache.brooklyn.core.location.Machines;
import org.apache.brooklyn.core.mgmt.BrooklynTaskTags;
import org.apache.brooklyn.core.mgmt.internal.EffectorUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.apache.brooklyn.location.ssh.SshMachineLocation;
import org.apache.brooklyn.api.location.MachineLocation;
import org.apache.brooklyn.util.core.config.ConfigBag;
import org.apache.brooklyn.util.core.task.DynamicSequentialTask;
import org.apache.brooklyn.util.core.task.DynamicTasks;
import org.apache.brooklyn.util.core.task.TaskBuilder;
import org.apache.brooklyn.util.core.task.Tasks;
import org.apache.brooklyn.util.javalang.Reflections;
import com.google.common.annotations.Beta;
import com.google.common.base.Preconditions;
/**
* Miscellaneous tasks which are useful in effectors.
* @since 0.6.0
*/
@Beta
public class EffectorTasks {
@SuppressWarnings("unused")
private static final Logger log = LoggerFactory.getLogger(EffectorTasks.class);
public interface EffectorTaskFactory<T> {
public abstract TaskAdaptable<T> newTask(Entity entity, Effector<T> effector, ConfigBag parameters);
}
/** wrapper for {@link EffectorBody} which simply runs that body on each invocation;
* the body must be thread safe and ideally stateless */
public static class EffectorBodyTaskFactory<T> implements EffectorTaskFactory<T> {
private final EffectorBody<T> effectorBody;
public EffectorBodyTaskFactory(EffectorBody<T> effectorBody) {
this.effectorBody = effectorBody;
}
@Override
public Task<T> newTask(final Entity entity, final org.apache.brooklyn.api.effector.Effector<T> effector, final ConfigBag parameters) {
final AtomicReference<DynamicSequentialTask<T>> dst = new AtomicReference<DynamicSequentialTask<T>>();
dst.set(new DynamicSequentialTask<T>(
getFlagsForTaskInvocationAt(entity, effector, parameters),
new Callable<T>() {
@Override
public T call() throws Exception {
try {
DynamicTasks.setTaskQueueingContext(dst.get());
return effectorBody.call(parameters);
} finally {
DynamicTasks.removeTaskQueueingContext();
}
}
}) {
@Override
public void handleException(Throwable throwable) throws Exception {
EffectorUtils.handleEffectorException(entity, effector, throwable);
}
});
return dst.get();
};
/** @deprecated since 0.7.0 use {@link #getFlagsForTaskInvocationAt(Entity, Effector, ConfigBag)} */ @Deprecated
protected final Map<Object,Object> getFlagsForTaskInvocationAt(Entity entity, Effector<?> effector) {
return getFlagsForTaskInvocationAt(entity, effector, null);
}
/** subclasses may override to add additional flags, but they should include the flags returned here
* unless there is very good reason not to; default impl returns a MutableMap */
protected Map<Object,Object> getFlagsForTaskInvocationAt(Entity entity, Effector<?> effector, ConfigBag parameters) {
return EffectorUtils.getTaskFlagsForEffectorInvocation(entity, effector, parameters);
}
}
/** wrapper for {@link EffectorTaskFactory} which ensures effector task tags are applied to it if needed
* (wrapping in a task if needed); without this, {@link EffectorBody}-based effectors get it by
* virtue of the call to {@link #getFlagsForTaskInvocationAt(Entity,Effector,ConfigBag)} therein
* but {@link EffectorTaskFactory}-based effectors generate a task without the right tags
* to be able to tell using {@link BrooklynTaskTags} the effector-context of the task
* <p>
* this gets applied automatically so marked as package-private */
static class EffectorMarkingTaskFactory<T> implements EffectorTaskFactory<T> {
private final EffectorTaskFactory<T> effectorTaskFactory;
public EffectorMarkingTaskFactory(EffectorTaskFactory<T> effectorTaskFactory) {
this.effectorTaskFactory = effectorTaskFactory;
}
@Override
public Task<T> newTask(final Entity entity, final org.apache.brooklyn.api.effector.Effector<T> effector, final ConfigBag parameters) {
if (effectorTaskFactory instanceof EffectorBodyTaskFactory)
return effectorTaskFactory.newTask(entity, effector, parameters).asTask();
// if we're in an effector context for this effector already, then also pass through
if (BrooklynTaskTags.isInEffectorTask(Tasks.current(), entity, effector, false))
return effectorTaskFactory.newTask(entity, effector, parameters).asTask();
// otherwise, create the task inside an appropriate effector body so tags, name, etc are set correctly
return new EffectorBodyTaskFactory<T>(new EffectorBody<T>() {
@Override
public T call(ConfigBag parameters) {
TaskAdaptable<T> t = DynamicTasks.queue(effectorTaskFactory.newTask(entity, effector, parameters));
return t.asTask().getUnchecked();
}
}).newTask(entity, effector, parameters);
}
}
public static <T> ConfigKey<T> asConfigKey(ParameterType<T> t) {
return ConfigKeys.newConfigKey(t.getParameterClass(), t.getName());
}
public static <T> ParameterTask<T> parameter(ParameterType<T> t) {
return new ParameterTask<T>(asConfigKey(t)).
name("parameter "+t);
}
public static <T> ParameterTask<T> parameter(Class<T> type, String name) {
return new ParameterTask<T>(ConfigKeys.newConfigKey(type, name)).
name("parameter "+name+" ("+type+")");
}
public static <T> ParameterTask<T> parameter(final ConfigKey<T> p) {
return new ParameterTask<T>(p);
}
public static class ParameterTask<T> implements EffectorTaskFactory<T> {
final ConfigKey<T> p;
private TaskBuilder<T> builder;
public ParameterTask(ConfigKey<T> p) {
this.p = p;
this.builder = Tasks.<T>builder().displayName("parameter "+p);
}
public ParameterTask<T> name(String taskName) {
builder.displayName(taskName);
return this;
}
@Override
public Task<T> newTask(Entity entity, Effector<T> effector, final ConfigBag parameters) {
return builder.body(new Callable<T>() {
@Override
public T call() throws Exception {
return parameters.get(p);
}
}).build();
}
}
public static <T> EffectorTaskFactory<T> of(final Task<T> task) {
return new EffectorTaskFactory<T>() {
@Override
public Task<T> newTask(Entity entity, Effector<T> effector, ConfigBag parameters) {
return task;
}
};
}
/** Finds the entity where this task is running
* @throws NullPointerException if there is none (no task, or no context entity for that task) */
public static Entity findEntity() {
return Preconditions.checkNotNull(BrooklynTaskTags.getTargetOrContextEntity(Tasks.current()),
"This must be executed in a task whose execution context has a target or context entity " +
"(i.e. it must be run from within an effector)");
}
/** Finds the entity where this task is running, casted to the given Entity subtype
* @throws NullPointerException if there is none
* @throws IllegalArgumentException if it is not of the indicated type */
public static <T extends Entity> T findEntity(Class<T> type) {
Entity t = findEntity();
return Reflections.cast(t, type);
}
/** Finds a unique {@link MachineLocation} attached to the entity
* where this task is running
* @throws NullPointerException if {@link #findEntity()} fails
* @throws IllegalStateException if call to {@link #getSshMachine(Entity)} fails */
public static <T extends MachineLocation> T findMachine(Class<T> clazz) {
return getMachine(findEntity(), clazz);
}
/** Finds a unique {@link MachineLocation} attached to the supplied entity
* @throws IllegalStateException if there is not a unique such {@link SshMachineLocation} */
public static <T extends MachineLocation> T getMachine(Entity entity, Class<T> clazz) {
try {
return Machines.findUniqueMachineLocation(entity.getLocations(), clazz).get();
} catch (Exception e) {
throw new IllegalStateException("Entity "+entity+" (in "+Tasks.current()+") requires a single " + clazz.getName() + ", but has "+entity.getLocations(), e);
}
}
/** Finds a unique {@link SshMachineLocation} attached to the entity
* where this task is running
* @throws NullPointerException if {@link #findEntity()} fails
* @throws IllegalStateException if call to {@link #getSshMachine(Entity)} fails */
public static SshMachineLocation findSshMachine() {
return getSshMachine(findEntity());
}
/** Finds a unique {@link SshMachineLocation} attached to the supplied entity
* @throws IllegalStateException if there is not a unique such {@link SshMachineLocation} */
public static SshMachineLocation getSshMachine(Entity entity) {
return getMachine(entity, SshMachineLocation.class);
}
}