org.elasticsearch.persistent.PersistentTasksNodeService Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of elasticsearch Show documentation
Show all versions of elasticsearch Show documentation
Elasticsearch subproject :server
/*
* Licensed to Elasticsearch under one or more contributor
* license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright
* ownership. Elasticsearch 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.elasticsearch.persistent;
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
import org.apache.logging.log4j.message.ParameterizedMessage;
import org.elasticsearch.action.ActionListener;
import org.elasticsearch.action.admin.cluster.node.tasks.cancel.CancelTasksResponse;
import org.elasticsearch.cluster.ClusterChangedEvent;
import org.elasticsearch.cluster.ClusterStateListener;
import org.elasticsearch.common.Strings;
import org.elasticsearch.common.io.stream.StreamInput;
import org.elasticsearch.common.io.stream.StreamOutput;
import org.elasticsearch.common.xcontent.XContentBuilder;
import org.elasticsearch.gateway.GatewayService;
import org.elasticsearch.tasks.Task;
import org.elasticsearch.tasks.TaskAwareRequest;
import org.elasticsearch.tasks.TaskId;
import org.elasticsearch.tasks.TaskManager;
import org.elasticsearch.persistent.PersistentTasksCustomMetaData.PersistentTask;
import java.io.IOException;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Map;
import java.util.Objects;
import java.util.Set;
import static java.util.Objects.requireNonNull;
/**
* This component is responsible for coordination of execution of persistent tasks on individual nodes. It runs on all
* non-transport client nodes in the cluster and monitors cluster state changes to detect started commands.
*/
public class PersistentTasksNodeService implements ClusterStateListener {
private static final Logger logger = LogManager.getLogger(PersistentTasksNodeService.class);
private final Map runningTasks = new HashMap<>();
private final PersistentTasksService persistentTasksService;
private final PersistentTasksExecutorRegistry persistentTasksExecutorRegistry;
private final TaskManager taskManager;
private final NodePersistentTasksExecutor nodePersistentTasksExecutor;
public PersistentTasksNodeService(PersistentTasksService persistentTasksService,
PersistentTasksExecutorRegistry persistentTasksExecutorRegistry,
TaskManager taskManager, NodePersistentTasksExecutor nodePersistentTasksExecutor) {
this.persistentTasksService = persistentTasksService;
this.persistentTasksExecutorRegistry = persistentTasksExecutorRegistry;
this.taskManager = taskManager;
this.nodePersistentTasksExecutor = nodePersistentTasksExecutor;
}
@Override
public void clusterChanged(ClusterChangedEvent event) {
if (event.state().blocks().hasGlobalBlock(GatewayService.STATE_NOT_RECOVERED_BLOCK)) {
// wait until the gateway has recovered from disk, otherwise if the only master restarts
// we start cancelling all local tasks before cluster has a chance to recover.
return;
}
PersistentTasksCustomMetaData tasks = event.state().getMetaData().custom(PersistentTasksCustomMetaData.TYPE);
PersistentTasksCustomMetaData previousTasks = event.previousState().getMetaData().custom(PersistentTasksCustomMetaData.TYPE);
// Cluster State Local State Local Action
// STARTED NULL Create as STARTED, Start
// STARTED STARTED Noop - running
// STARTED COMPLETED Noop - waiting for notification ack
// NULL NULL Noop - nothing to do
// NULL STARTED Remove locally, Mark as PENDING_CANCEL, Cancel
// NULL COMPLETED Remove locally
// Master states:
// NULL - doesn't exist in the cluster state
// STARTED - exist in the cluster state
// Local state:
// NULL - we don't have task registered locally in runningTasks
// STARTED - registered in TaskManager, requires master notification when finishes
// PENDING_CANCEL - registered in TaskManager, doesn't require master notification when finishes
// COMPLETED - not registered in TaskManager, notified, waiting for master to remove it from CS so we can remove locally
// When task finishes if it is marked as STARTED or PENDING_CANCEL it is marked as COMPLETED and unregistered,
// If the task was STARTED, the master notification is also triggered (this is handled by unregisterTask() method, which is
// triggered by PersistentTaskListener
if (Objects.equals(tasks, previousTasks) == false || event.nodesChanged()) {
// We have some changes let's check if they are related to our node
String localNodeId = event.state().getNodes().getLocalNodeId();
Set notVisitedTasks = new HashSet<>(runningTasks.keySet());
if (tasks != null) {
for (PersistentTask taskInProgress : tasks.tasks()) {
if (localNodeId.equals(taskInProgress.getExecutorNode())) {
Long allocationId = taskInProgress.getAllocationId();
AllocatedPersistentTask persistentTask = runningTasks.get(allocationId);
if (persistentTask == null) {
// New task - let's start it
startTask(taskInProgress);
} else {
// The task is still running
notVisitedTasks.remove(allocationId);
}
}
}
}
for (Long id : notVisitedTasks) {
AllocatedPersistentTask task = runningTasks.get(id);
if (task.isCompleted()) {
// Result was sent to the caller and the caller acknowledged acceptance of the result
logger.trace("Found completed persistent task [{}] with id [{}] and allocation id [{}] - removing",
task.getAction(), task.getPersistentTaskId(), task.getAllocationId());
runningTasks.remove(id);
} else {
// task is running locally, but master doesn't know about it - that means that the persistent task was removed
// cancel the task without notifying master
logger.trace("Found unregistered persistent task [{}] with id [{}] and allocation id [{}] - cancelling",
task.getAction(), task.getPersistentTaskId(), task.getAllocationId());
cancelTask(id);
}
}
}
}
private void startTask(PersistentTask taskInProgress) {
PersistentTasksExecutor executor =
persistentTasksExecutorRegistry.getPersistentTaskExecutorSafe(taskInProgress.getTaskName());
TaskAwareRequest request = new TaskAwareRequest() {
TaskId parentTaskId = new TaskId("cluster", taskInProgress.getAllocationId());
@Override
public void setParentTask(TaskId taskId) {
throw new UnsupportedOperationException("parent task if for persistent tasks shouldn't change");
}
@Override
public TaskId getParentTask() {
return parentTaskId;
}
@Override
public Task createTask(long id, String type, String action, TaskId parentTaskId, Map headers) {
return executor.createTask(id, type, action, parentTaskId, taskInProgress, headers);
}
};
AllocatedPersistentTask task = (AllocatedPersistentTask) taskManager.register("persistent", taskInProgress.getTaskName() + "[c]",
request);
boolean processed = false;
try {
task.init(persistentTasksService, taskManager, logger, taskInProgress.getId(), taskInProgress.getAllocationId());
logger.trace("Persistent task [{}] with id [{}] and allocation id [{}] was created", task.getAction(),
task.getPersistentTaskId(), task.getAllocationId());
try {
runningTasks.put(taskInProgress.getAllocationId(), task);
nodePersistentTasksExecutor.executeTask(taskInProgress.getParams(), taskInProgress.getState(), task, executor);
} catch (Exception e) {
// Submit task failure
task.markAsFailed(e);
}
processed = true;
} finally {
if (processed == false) {
// something went wrong - unregistering task
logger.warn("Persistent task [{}] with id [{}] and allocation id [{}] failed to create", task.getAction(),
task.getPersistentTaskId(), task.getAllocationId());
taskManager.unregister(task);
}
}
}
/**
* Unregisters and then cancels the locally running task using the task manager. No notification to master will be send upon
* cancellation.
*/
private void cancelTask(Long allocationId) {
AllocatedPersistentTask task = runningTasks.remove(allocationId);
if (task.markAsCancelled()) {
// Cancel the local task using the task manager
String reason = "task has been removed, cancelling locally";
persistentTasksService.sendCancelRequest(task.getId(), reason, new ActionListener() {
@Override
public void onResponse(CancelTasksResponse cancelTasksResponse) {
logger.trace("Persistent task [{}] with id [{}] and allocation id [{}] was cancelled", task.getAction(),
task.getPersistentTaskId(), task.getAllocationId());
}
@Override
public void onFailure(Exception e) {
// There is really nothing we can do in case of failure here
logger.warn(() -> new ParameterizedMessage(
"failed to cancel task [{}] with id [{}] and allocation id [{}]",
task.getAction(), task.getPersistentTaskId(), task.getAllocationId()), e);
}
});
}
}
public static class Status implements Task.Status {
public static final String NAME = "persistent_executor";
private final AllocatedPersistentTask.State state;
public Status(AllocatedPersistentTask.State state) {
this.state = requireNonNull(state, "State cannot be null");
}
public Status(StreamInput in) throws IOException {
state = AllocatedPersistentTask.State.valueOf(in.readString());
}
@Override
public String getWriteableName() {
return NAME;
}
@Override
public XContentBuilder toXContent(XContentBuilder builder, Params params) throws IOException {
builder.startObject();
builder.field("state", state.toString());
builder.endObject();
return builder;
}
@Override
public void writeTo(StreamOutput out) throws IOException {
out.writeString(state.toString());
}
@Override
public String toString() {
return Strings.toString(this);
}
@Override
public boolean isFragment() {
return false;
}
@Override
public boolean equals(Object o) {
if (this == o) return true;
if (o == null || getClass() != o.getClass()) return false;
Status status = (Status) o;
return state == status.state;
}
@Override
public int hashCode() {
return Objects.hash(state);
}
}
}