distributedlog-core/src/main/java/org/apache/distributedlog/DistributedLogConstants.java

/**
 * 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.distributedlog;

import java.util.List;
import java.util.concurrent.TimeUnit;

import com.google.common.collect.ImmutableList;
import org.apache.zookeeper.ZooDefs.Ids;
import org.apache.zookeeper.data.ACL;

import static com.google.common.base.Charsets.UTF_8;

/**
 * Constants used in DistributedLog.
 */
public class DistributedLogConstants {
    public static final byte[] EMPTY_BYTES = new byte[0];
    public static final String SCHEME_PREFIX = "distributedlog";
    public static final String BACKEND_BK = "bk";
    public static final long INVALID_TXID = -999;
    public static final long EMPTY_LOGSEGMENT_TX_ID = -99;
    public static final long MAX_TXID = Long.MAX_VALUE;
    public static final long SMALL_LOGSEGMENT_THRESHOLD = 10;
    public static final int LOGSEGMENT_NAME_VERSION = 1;
    public static final int FUTURE_TIMEOUT_IMMEDIATE = 0;
    public static final int FUTURE_TIMEOUT_INFINITE = -1;
    public static final long LOCK_IMMEDIATE = FUTURE_TIMEOUT_IMMEDIATE;
    public static final long LOCK_TIMEOUT_INFINITE = FUTURE_TIMEOUT_INFINITE;
    public static final long LOCK_OP_TIMEOUT_DEFAULT = 120;
    public static final long LOCK_REACQUIRE_TIMEOUT_DEFAULT = 120;
    public static final String UNKNOWN_CLIENT_ID = "Unknown-ClientId";
    public static final int LOCAL_REGION_ID = 0;
    public static final long LOGSEGMENT_DEFAULT_STATUS = 0;
    public static final long UNASSIGNED_LOGSEGMENT_SEQNO = 0;
    public static final long UNASSIGNED_SEQUENCE_ID = -1L;
    public static final long FIRST_LOGSEGMENT_SEQNO = 1;
    public static final long UNRESOLVED_LEDGER_ID = -1;
    public static final long LATENCY_WARN_THRESHOLD_IN_MILLIS = TimeUnit.SECONDS.toMillis(1);
    public static final int DL_INTERRUPTED_EXCEPTION_RESULT_CODE = Integer.MIN_VALUE + 1;
    public static final int ZK_CONNECTION_EXCEPTION_RESULT_CODE = Integer.MIN_VALUE + 2;

    public static final String ALLOCATION_POOL_NODE = ".allocation_pool";
    // log segment prefix
    public static final String INPROGRESS_LOGSEGMENT_PREFIX = "inprogress";
    public static final String COMPLETED_LOGSEGMENT_PREFIX = "logrecs";
    public static final String DISALLOW_PLACEMENT_IN_REGION_FEATURE_NAME = "disallow_bookie_placement";
    static final byte[] CONTROL_RECORD_CONTENT = "control".getBytes(UTF_8);
    static final byte[] KEEPALIVE_RECORD_CONTENT = "keepalive".getBytes(UTF_8);

    // An ACL that gives all permissions to node creators and read permissions only to everyone else.
    public static final List<ACL> EVERYONE_READ_CREATOR_ALL =
        ImmutableList.<ACL>builder()
            .addAll(Ids.CREATOR_ALL_ACL)
            .addAll(Ids.READ_ACL_UNSAFE)
            .build();
}