/*
* SonarQube
* Copyright (C) 2009-2017 SonarSource SA
* mailto:info AT sonarsource DOT com
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 3 of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program; if not, write to the Free Software Foundation,
* Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
package org.sonar.ce.queue;
import java.util.Optional;
import java.util.Set;
import javax.annotation.Nullable;
import org.sonar.db.ce.CeActivityDto.Status;
/**
* Queue of pending Compute Engine tasks. Both producer and consumer actions
* are implemented.
* <p>
* This class is decoupled from the regular task type {@link org.sonar.db.ce.CeTaskTypes#REPORT}.
* </p>
*/
public interface InternalCeQueue extends CeQueue {
/**
* Peek the oldest task in status {@link org.sonar.db.ce.CeQueueDto.Status#PENDING}.
* The task status is changed to {@link org.sonar.db.ce.CeQueueDto.Status#IN_PROGRESS}.
* Does not return anything if the queue is paused (see {@link #isPeekPaused()}.
*
* <p>Only a single task can be peeked by project.</p>
*
* <p>An unchecked exception may be thrown on technical errors (db connection, ...).</p>
*
* <p>Tasks which have been executed twice already but are still {@link org.sonar.db.ce.CeQueueDto.Status#PENDING}
* are ignored</p>
*/
Optional<CeTask> peek(String workerUuid);
/**
* Removes all the tasks from the queue, whatever their status. They are marked
* as {@link Status#CANCELED} in past activity.
* This method can NOT be called when workers are being executed, as in progress
* tasks can't be killed.
*
* @return the number of canceled tasks
*/
int clear();
/**
* Removes a task from the queue and registers it to past activities. This method
* is called by Compute Engine workers when task is processed and can include an option {@link CeTaskResult} object.
*
* @throws IllegalStateException if the task does not exist in the queue
* @throws IllegalArgumentException if {@code error} is non {@code null} but {@code status} is not {@link Status#FAILED}
*/
void remove(CeTask task, Status status, @Nullable CeTaskResult taskResult, @Nullable Throwable error);
void cancelWornOuts();
void resetTasksWithUnknownWorkerUUIDs(Set<String> knownWorkerUUIDs);
void pausePeek();
void resumePeek();
boolean isPeekPaused();
}