| /* |
| * Copyright (C) 2016, Google Inc. and others |
| * |
| * This program and the accompanying materials are made available under the |
| * terms of the Eclipse Distribution License v. 1.0 which is available at |
| * https://www.eclipse.org/org/documents/edl-v10.php. |
| * |
| * SPDX-License-Identifier: BSD-3-Clause |
| */ |
| |
| package org.eclipse.jgit.internal.ketch; |
| |
| import static org.eclipse.jgit.internal.ketch.KetchReplica.State.OFFLINE; |
| |
| import java.util.ArrayList; |
| import java.util.Collection; |
| import java.util.Collections; |
| import java.util.List; |
| |
| import org.eclipse.jgit.annotations.Nullable; |
| import org.eclipse.jgit.lib.ObjectId; |
| |
| /** |
| * A snapshot of a leader and its view of the world. |
| */ |
| public class LeaderSnapshot { |
| final List<ReplicaSnapshot> replicas = new ArrayList<>(); |
| KetchLeader.State state; |
| long term; |
| LogIndex headIndex; |
| LogIndex committedIndex; |
| boolean idle; |
| |
| LeaderSnapshot() { |
| } |
| |
| /** |
| * Get unmodifiable view of configured replicas. |
| * |
| * @return unmodifiable view of configured replicas. |
| */ |
| public Collection<ReplicaSnapshot> getReplicas() { |
| return Collections.unmodifiableList(replicas); |
| } |
| |
| /** |
| * Get current state of the leader. |
| * |
| * @return current state of the leader. |
| */ |
| public KetchLeader.State getState() { |
| return state; |
| } |
| |
| /** |
| * Whether the leader is not running a round to reach consensus, and has no |
| * rounds queued. |
| * |
| * @return {@code true} if the leader is not running a round to reach |
| * consensus, and has no rounds queued. |
| */ |
| public boolean isIdle() { |
| return idle; |
| } |
| |
| /** |
| * Get term of this leader |
| * |
| * @return term of this leader. Valid only if {@link #getState()} is |
| * currently |
| * {@link org.eclipse.jgit.internal.ketch.KetchLeader.State#LEADER}. |
| */ |
| public long getTerm() { |
| return term; |
| } |
| |
| /** |
| * Get end of the leader's log |
| * |
| * @return end of the leader's log; null if leader hasn't started up enough |
| * to begin its own election. |
| */ |
| @Nullable |
| public LogIndex getHead() { |
| return headIndex; |
| } |
| |
| /** |
| * Get state the leader knows is committed on a majority of participant |
| * replicas |
| * |
| * @return state the leader knows is committed on a majority of participant |
| * replicas. Null until the leader instance has committed a log |
| * index within its own term. |
| */ |
| @Nullable |
| public LogIndex getCommitted() { |
| return committedIndex; |
| } |
| |
| /** {@inheritDoc} */ |
| @Override |
| public String toString() { |
| StringBuilder s = new StringBuilder(); |
| s.append(isIdle() ? "IDLE" : "RUNNING"); //$NON-NLS-1$ //$NON-NLS-2$ |
| s.append(" state ").append(getState()); //$NON-NLS-1$ |
| if (getTerm() > 0) { |
| s.append(" term ").append(getTerm()); //$NON-NLS-1$ |
| } |
| s.append('\n'); |
| s.append(String.format( |
| "%-10s %12s %12s\n", //$NON-NLS-1$ |
| "Replica", "Accepted", "Committed")); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$ |
| s.append("------------------------------------\n"); //$NON-NLS-1$ |
| debug(s, "(leader)", getHead(), getCommitted()); //$NON-NLS-1$ |
| s.append('\n'); |
| for (ReplicaSnapshot r : getReplicas()) { |
| debug(s, r); |
| s.append('\n'); |
| } |
| s.append('\n'); |
| return s.toString(); |
| } |
| |
| private static void debug(StringBuilder b, ReplicaSnapshot s) { |
| KetchReplica replica = s.getReplica(); |
| debug(b, replica.getName(), s.getAccepted(), s.getCommitted()); |
| b.append(String.format(" %-8s %s", //$NON-NLS-1$ |
| replica.getParticipation(), s.getState())); |
| if (s.getState() == OFFLINE) { |
| String err = s.getErrorMessage(); |
| if (err != null) { |
| b.append(" (").append(err).append(')'); //$NON-NLS-1$ |
| } |
| } |
| } |
| |
| private static void debug(StringBuilder s, String name, |
| ObjectId accepted, ObjectId committed) { |
| s.append(String.format( |
| "%-10s %-12s %-12s", //$NON-NLS-1$ |
| name, str(accepted), str(committed))); |
| } |
| |
| static String str(ObjectId c) { |
| if (c instanceof LogIndex) { |
| return ((LogIndex) c).describeForLog(); |
| } else if (c != null) { |
| return c.abbreviate(8).name(); |
| } |
| return "-"; //$NON-NLS-1$ |
| } |
| } |