c5db.replication.SingleNodeFakeReplicator.java Source code

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Here is the source code for c5db.replication.SingleNodeFakeReplicator.java

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/*
 * Copyright 2014 WANdisco
 *
 *  WANdisco 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 c5db.replication;

import c5db.interfaces.replication.IndexCommitNotice;
import c5db.interfaces.replication.QuorumConfiguration;
import c5db.interfaces.replication.Replicator;
import c5db.interfaces.replication.ReplicatorInstanceEvent;
import c5db.interfaces.replication.ReplicatorReceipt;
import com.google.common.collect.Sets;
import com.google.common.util.concurrent.Futures;
import com.google.common.util.concurrent.ListenableFuture;
import com.google.common.util.concurrent.SettableFuture;
import org.jetlang.channels.Channel;
import org.jetlang.channels.MemoryChannel;
import org.jetlang.channels.Subscriber;
import org.jetlang.fibers.Fiber;

import java.nio.ByteBuffer;
import java.util.Collection;
import java.util.List;

public class SingleNodeFakeReplicator implements Replicator {
    private final long nodeId;
    private final String quorumId;

    private final Channel<State> stateChannel = new MemoryChannel<>();
    private final Channel<ReplicatorInstanceEvent> eventChannel = new MemoryChannel<>();
    private final Channel<IndexCommitNotice> commitNoticeChannel = new MemoryChannel<>();
    private final Fiber fiber;

    private long nextSeqNum = 1;
    private long term = 1;
    private State state = State.FOLLOWER;

    public SingleNodeFakeReplicator(Fiber fiber, long nodeId, String quorumId) {
        this.fiber = fiber;
        this.nodeId = nodeId;
        this.quorumId = quorumId;
    }

    @Override
    public String getQuorumId() {
        return quorumId;
    }

    @Override
    public ListenableFuture<QuorumConfiguration> getQuorumConfiguration() {
        return Futures.immediateFuture(QuorumConfiguration.of(Sets.newHashSet(nodeId)));
    }

    @Override
    public ListenableFuture<ReplicatorReceipt> changeQuorum(Collection<Long> newPeers) throws InterruptedException {
        throw new UnsupportedOperationException();
    }

    @Override
    public synchronized ListenableFuture<ReplicatorReceipt> logData(List<ByteBuffer> data) {
        SettableFuture<ReplicatorReceipt> receiptFuture = SettableFuture.create();
        final long thisSeqNum = nextSeqNum;
        nextSeqNum++;

        doLater(() -> {
            receiptFuture.set(new ReplicatorReceipt(term, thisSeqNum));
            doLater(() -> commitNoticeChannel
                    .publish(new IndexCommitNotice(quorumId, nodeId, thisSeqNum, thisSeqNum, term)));
        });

        return receiptFuture;
    }

    @Override
    public long getId() {
        return nodeId;
    }

    public void start() {
        state = State.LEADER;
        doLater(() -> stateChannel.publish(state));
    }

    @Override
    public Subscriber<State> getStateChannel() {
        return stateChannel;
    }

    @Override
    public Subscriber<ReplicatorInstanceEvent> getEventChannel() {
        return eventChannel;
    }

    @Override
    public Subscriber<IndexCommitNotice> getCommitNoticeChannel() {
        return commitNoticeChannel;
    }

    private void doLater(Runnable runnable) {
        fiber.execute(runnable);
    }
}