ReadOnlyCommands.java

/*
 * Copyright 2011-2016 the original author or authors.
 *
 * Licensed 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 com.lambdaworks.redis.cluster;

import java.util.Collections;
import java.util.EnumSet;
import java.util.Set;

import com.lambdaworks.redis.protocol.CommandType;
import com.lambdaworks.redis.protocol.ProtocolKeyword;

/**
 * Contains all command names that are read-only commands.
 *
 * @author Mark Paluch
 */
class ReadOnlyCommands {

    private static final Set<CommandType> READ_ONLY_COMMANDS = EnumSet.noneOf(CommandType.class);

    static {
        for (CommandName commandNames : CommandName.values()) {
            READ_ONLY_COMMANDS.add(CommandType.valueOf(commandNames.name()));
        }
    }

    /**
     * @param protocolKeyword must not be {@literal null}.
     * @return {@literal true} if {@link ProtocolKeyword} is a read-only command.
     */
    public static boolean isReadOnlyCommand(ProtocolKeyword protocolKeyword) {
        return READ_ONLY_COMMANDS.contains(protocolKeyword);
    }

    /**
     * @return an unmodifiable {@link Set} of {@link CommandType read-only} commands.
     */
    public static Set<CommandType> getReadOnlyCommands() {
        return Collections.unmodifiableSet(READ_ONLY_COMMANDS);
    }

    enum CommandName {
        ASKING, BITCOUNT, BITPOS, CLIENT, COMMAND, DUMP, ECHO, EVAL, EVALSHA, EXISTS, //
        GEODIST, GEOPOS, GEORADIUS, GEORADIUSBYMEMBER, GEOHASH, GET, GETBIT, //
        GETRANGE, HEXISTS, HGET, HGETALL, HKEYS, HLEN, HMGET, HSCAN, HSTRLEN, //
        HVALS, INFO, KEYS, LINDEX, LLEN, LRANGE, MGET, MULTI, PFCOUNT, PTTL, //
        RANDOMKEY, READWRITE, SCAN, SCARD, SCRIPT, //
        SDIFF, SINTER, SISMEMBER, SMEMBERS, SRANDMEMBER, SSCAN, STRLEN, //
        SUNION, TIME, TTL, TYPE, ZCARD, ZCOUNT, ZLEXCOUNT, ZRANGE, //
        ZRANGEBYLEX, ZRANGEBYSCORE, ZRANK, ZREVRANGE, ZREVRANGEBYLEX, ZREVRANGEBYSCORE, ZREVRANK, ZSCAN, ZSCORE, //

        // Pub/Sub commands are no key-space commands so they are safe to execute on slave nodes
        PUBLISH, PUBSUB, PSUBSCRIBE, PUNSUBSCRIBE, SUBSCRIBE, UNSUBSCRIBE
    }
}