//使用autoload加载相关库,这边重点就是为了require $file;
spl_autoload_register(function($class) {
     $file = __DIR__ . '/lib/Predis/' . $class . '.php';
     if (file_exists($file))  {
         require  $file;
         return  true;
     }
});


//配置连接的IP、端口、以及相应的数据库
$server = array (
     'host'     => '127.0.0.1',
     'port'     => 6379,
     'database' => 15
);
$redis = new Client($server);



//普通set/get操作
$redis->set('library', 'predis');
$retval = $redis->get('library');
echo  $retval;  //显示 'predis'

//setex set一个存储时效
$redis->setex('str', 10, 'bar');  //表示存储有效期为10秒

//setnx/msetnx相当于add操作,不会覆盖已有值
$redis->setnx('foo', 12);  //true
$redis->setnx('foo', 34);  //false

//getset操作,set的变种,结果返回替换前的值
$redis->getset('foo', 56); //返回34

// incrby/incr/decrby/decr 对值的递增和递减
$redis->incr('foo');  //foo为57
$redis->incrby('foo', 2);  //foo为59

//exists检测是否存在某值
$redis->exists('foo'); //true

//del 删除
$redis->del('foo'); //true

//type 类型检测,字符串返回string,列表返回 list,set表返回set/zset,hash表返回hash
$redis->type('foo'); //不存在,返回none
$redis->set('str', 'test'); 
$redis->type('str');  //字符串，返回string

//append 连接到已存在字符串
$redis->append('str', '_123');  //返回累加后的字符串长度8,此进str为 'test_123'

//setrange 部分替换操作
$redis->setrange('str', 0, 'abc');  //返回3,参数2为0时等同于set操作
$redis->setrange('str', 2, 'cd'); //返回4,表示从第2个字符后替换,这时'str'为'abcd'

//substr 部分获取操作
$redis->substr('str', 0, 2); //表示从第0个起，取到第2个字符，共3个，返回'abc'

//strlen 获取字符串长度
$redis->strlen('str');  //返回4

//setbit/getbit 位存储和获取
$redis->setbit('binary', 31, 1);   //表示在第31位存入1,这边可能会有大小端问题?
                                   //不过没关系,getbit 应该不会有问题
$redis->getbit('binary', 31);      //返回1

//keys 模糊查找功能,支持*号以及?号(匹配一个字符)
$redis->set('foo1', 123);
$redis->set('foo2', 456);
$redis->keys('foo*');  //返回foo1和foo2的array
$redis->keys('f?o?');   //同上

//randomkey 随机返回一个key
$redis->randomkey();  //可能是返回 'foo1'或者是'foo2'及其它任何一存在redis的key

//rename/renamenx 对key进行改名,所不同的是renamenx不允许改成已存在的key
$redis->rename('str', 'str2');  //把原先命名为'str'的key改成了'str2'

//expire 设置key-value的时效性,ttl 获取剩余有效期,persist 重新设置为永久存储
$redis->expire('foo', 1);  //设置有效期为1秒
$redis->ttl('foo');  //返回有效期值1s
$redis->expire('foo');  //取消expire行为

//dbsize 返回redis当前数据库的记录总数
$redis->dbsize();

/*
队列操作
*/

// rpush/rpushx 有序列表操作,从队列后插入元素
// lpush/lpushx 和rpush/rpushx的区别是插入到队列的头部,同上
// 'x'含义是只对已存在的key进行操作
$redis->rpush('fooList', 'bar1');  //返回一个列表的长度1
$redis->lpush('fooList', 'bar0');  //返回一个列表的长度2
$redis->rpushx('fooList', 'bar2');  //返回3,rpushx只对已存在的队列做添加,否则返回0
//llen返回当前列表长度
$redis->llen('fooList'); //3

//lrange 返回队列中一个区间的元素
$redis->lrange('fooList', 0, 1);  //返回数组包含第0个至第1个共2个元素
//返回第0个至倒数第一个,相当于返回所有元素,注意redis中很多时候会用到负数,下同
$redis->lrange('fooList', 0,- 1);

//lindex 返回指定顺序位置的list元素
$redis->lindex('fooList', 1);  //返回'bar1'

//lset 修改队列中指定位置的value
$redis->lset('fooList', 1, '123'); //修改位置1的元素,返回true

//lrem 删除队列中左起指定数量的字符
$redis->lrem('fooList', 1, '_');  //删除队列中左起(右起使用-1)1个字符'_'(若有)

//lpop/rpop 类似栈结构地弹出(并删除)最左或最右的一个元素
$redis->lpop('fooList');  //'bar0'
$redis->rpop('fooList');  //'bar2'

//ltrim 队列修改，保留左边起若干元素，其余删除
$redis->ltrim('fooList', 0, 1);  //保留左边起第0个至第1个元素

//rpoplpush 从一个队列中pop出元素并push到另一个队列
$redis->rpush('list1', 'ab0');
$redis->rpush('list1', 'ab1');
$redis->rpush('list2', 'ab2');
$redis->rpush('list2', 'ab3');
//结果list1 => array('ab0'),list2 => array('ab1','ab2','ab3')
$redis->rpoplpush('list1', 'list2');
//也适用于同一个队列,把最后一个元素移到头部list2 => array('ab3','ab1','ab2')
$redis->rpoplpush('list2', 'list2');

//linsert 在队列的中间指定元素前或后插入元素
$redis->linsert('list2', 'before', 'ab1', '123');  //表示在元素'ab1'之前插入'123'
$redis->linsert('list2', 'after', 'ab1', '456');    //表示在元素'ab1'之后插入'456'


//blpop/brpop 阻塞并等待一个列队不为空时，再pop出最左或最右的一个元素
//brpoplpush 同样是阻塞并等待操作，结果同rpoplpush一样
$redis->blpop('list3', 10);  //如果list3为空则一直等待,直到不为空时将第一元素弹出,10秒后超时



/**
set表操作
*/

//sadd 增加元素,返回true,重复返回false
$redis->sadd('set1', 'ab');
$redis->sadd('set1', 'cd');
$redis->sadd('set1', 'ef');

//srem 移除指定元素
$redis->srem('set1', 'cd');  //删除'cd'元素

//spop 弹出首元素
$redis->spop('set1');

//smove 移动当前set表的指定元素到另一个set表
$redis->sadd('set2', '123');
//移动'set1'中的'ab'到'set2',返回true or false
$redis->smove('set1', 'set2', 'ab');

//scard 返回当前set表元素个数
$redis->scard('set2'); //2

//sismember 判断元素是否属于当前表
$redis->sismember('set2', '123');  //true or false

//smembers 返回当前表的所有元素
$redis->smembers('set2');  //array('123','ab');

//sinter/sunion/sdiff  返回两个表中元素的交集/并集/补集
$redis->sadd('set1', 'ab');
$redis->sinter('set2', 'set1');  //返回array('ab')

//sinterstore/sunionstore/sdiffstore 将两个表交集/并集/补集元素copy到第三个表中
$redis->set('foo', 0);
//这边等同于将'set1'的内容copy到'foo'中，并将'foo'转为set表
$redis->sinterstore('foo', 'set1');
//将'set1'和'set2'中相同的元素copy到'foo'表中,覆盖'foo'原有内容
$redis->sinterstore('foo', array('set1', 'set2'));

//srandmember 返回表中一个随机元素
$redis->srandmember('set1');

/**
有序set表操作
*/

//sadd 增加元素,并设置序号,返回true,重复返回false
$redis->zadd('zset1', 1, 'ab');
$redis->zadd('zset1', 2, 'cd');
$redis->zadd('zset1', 3, 'ef');

//zincrby 对指定元素索引值的增减,改变元素排列次序
$redis->zincrby('zset1', 10, 'ab'); //返回11

//zrem 移除指定元素
$redis->zrem('zset1', 'ef');  //true or false

//zrange 按位置次序返回表中指定区间的元素
$redis->zrange('zset1', 0, 1);  //返回位置0和1之间(两个)的元素
$redis->zrange('zset1', 0,- 1); //返回位置0和倒数第一个元素之间的元素(相当于所有元素)

//zrevrange 同上,返回表中指定区间的元素,按次序倒排
$redis->zrevrange('zset1', 0,- 1);  //元素顺序和zrange相反

//zrangebyscore/zrevrangebyscore 按顺序/降序返回表中指定索引区间的元素
$redis->zadd('zset1', 3, 'ef');
$redis->zadd('zset1', 5, 'gh');
$redis->zrangebyscore('zset1', 2, 9);  //返回索引值2-9之间的元素 array('ef','gh')
//参数形式
//返回索引值2-9之间的元素并包含索引值 array(array('ef',3),array('gh',5))
$redis->zrangebyscore('zset1', 2, 9, 'withscores');  
// 返回索引值2-9之间的元素,'withscores' => true表示包含索引值;
// 'limit'=>array(1, 2),表示最多返回2条,结果为array(array('ef',3),array('gh',5))
$redis->zrangebyscore('zset1', 2, 9, array('withscores' =>  true, 'limit' =>  array(1, 2)));  

//zunionstore/zinterstore 将多个表的并集/交集存入另一个表中
//将'zset1','zset2','zset0'的并集存入'zset3'
$redis->zunionstore('zset3', array('zset1', 'zset2', 'zset0'));  
//其它参数 
//weights参数表示权重，其中表示并集后值大于5的元素排在前，大于0的排在后
$redis->zunionstore('zset3', array('zset1', 'zset2'), array('weights' => array(5, 0))); 
 //'aggregate' =>  'max'或'min'表示并集后相同的元素是取大值或是取小值
$redis->zunionstore('zset3', array('zset1', 'zset2'), array('aggregate' => 'max'));

//zcount 统计一个索引区间的元素个数
$redis->zcount('zset1', 3, 5); //2
//'(3'表示索引值在3-5之间但不含3,同理也可以使用'(5'表示上限为5但不含5
$redis->zcount('zset1', '(3', 5));

//zcard 统计元素个数
$redis->zcard('zset1'); //4

//zscore 查询元素的索引
$redis->zscore('zset1', 'ef'); //3

//zremrangebyscore 删除一个索引区间的元素
$redis->zremrangebyscore('zset1', 0, 2);  //删除索引在0-2之间的元素('ab','cd'),返回删除元素个数2

//zrank/zrevrank 返回元素所在表顺序/降序的位置(不是索引)
$redis->zrank('zset1', 'ef'); //返回0,因为它是第一个元素;zrevrank则返回1(最后一个)

//zremrangebyrank 删除表中指定位置区间的元素
$redis->zremrangebyrank('zset1', 0, 10);  //删除位置为0-10的元素,返回删除的元素个数2 


/**
hash表操作
*/

//hset/hget 存取hash表的数据
$redis->hset('hash1', 'key1', 'v1');  //将key为'key1' value为'v1'的元素存入hash1表
$redis->hset('hash1', 'key2', 'v2');
$redis->hget('hash1', 'key1');   //取出表'hash1'中的key 'key1'的值,返回'v1'

//hexists 返回hash表中的指定key是否存在
$redis->hexists ('hash1', 'key1');  //true or false

//hdel 删除hash表中指定key的元素
$redis->hdel('hash1', 'key2');  //true or false

//hlen 返回hash表元素个数
$redis->hlen('hash1');  //1

//hsetnx 增加一个元素,但不能重复
$redis->hsetnx('hash1', 'key1', 'v2');  //false
$redis->hsetnx('hash1', 'key2', 'v2');  //true

//hmset/hmget 存取多个元素到hash表
$redis->hmset('hash1', array('key3' =>  'v3', 'key4' =>  'v4')); 
$redis->hmget('hash1', array('key3', 'key4'));  //返回相应的值 array('v3','v4')

//hincrby 对指定key进行累加
$redis->hincrby('hash1', 'key5', 3);  //返回3
$redis->hincrby('hash1', 'key5', 10);  //返回13

//hkeys 返回hash表中的所有key
$redis->hkeys('hash1');  //返回array('key1','key2','key3','key4','key5')

//hvals 返回hash表中的所有value
$redis->hvals('hash1');  //返回array('v1','v2','v3','v4',13)

//hgetall 返回整个hash表元素
//返回array('key1'=>'v1','key2'=>'v2','key3'=>'v3','key4'=>'v4','key5'=>13)
$redis->hgetall('hash1');

/**
排序操作
*/

//sort 排序
$redis->rpush('tab', 3);
$redis->rpush('tab', 2);
$redis->rpush('tab', 17);
$redis->sort('tab');   //返回array(2,3,17)
//使用参数,可组合使用 array('sort' =>  'desc','limit' =>  array(1, 2))
$redis->sort('tab', array('sort' => 'desc'));   //降序排列,返回array(17,3,2)
//返回顺序位置中1的元素2个(这里的2是指个数,而不是位置),返回array(3,17)
$redis->sort('tab', array('limit' => array(1, 2)));
//按首字符排序返回array(17,2,3),因为17的首字符是'1'所以排首位置
$redis->sort('tab', array('limit' =>  array('alpha' => true)));
//表示永久性排序,返回元素个数
$redis->sort('tab', array('limit' => array('store' => 'ordered')));
//使用了通配符'*'过滤元素,表示只返回以'pre_'开头的元素
$redis->sort('tab', array('limit' => array('get' => 'pre_*')));

/**
redis管理操作
*/

//select 指定要操作的数据库
$redis->select('mydb');  //指定为mydb,不存在则创建

//flushdb 清空当前库
$redis->flushdb();

//move 移动当库的元素到其它库
$redis->set('foo', 'bar');
$redis->move('foo', 'mydb2');  //若'mydb2'库存在

//info 显示服务当状态信息
$redis->info();

//slaveof 配置从服务器
//配置127.0.0.1端口80的服务器为从服务器
$redis->slaveof('127.0.0.1', 80);
$redis->slaveof();  //清除从服务器

//同步保存服务器数据到磁盘
$redis->save();
//异步保存服务器数据到磁盘
$redis->bgsave();
//??
$redis->bgrewriteaof();
//返回最后更新磁盘的时间
$redis->lastsave();


//set/get多个key-value
$mkv = array (
     'usr:0001' => 'First user',
     'usr:0002' => 'Second user',
     'usr:0003' => 'Third user'
);
$redis->mset($mkv);  //存储多个key对应的value
$retval = $redis->mget(array_keys($mkv));  //获取多个key对应的value
print_r($retval);



//批量操作
$replies = $redis->pipeline(function($pipe) {
     $pipe->ping();
     $pipe->flushdb();
     $pipe->incrby('counter', 10);  //增量操作
     $pipe->incrby('counter', 30);
     $pipe->exists('counter');
     $pipe->get('counter');
     $pipe->mget('does_not_exist', 'counter');  
});
print_r($replies);

//CAS,事务性操作
function zpop($client, $zsetKey) {
     $element = null;
     $options = array (
         'cas'   => true,     // Initialize with support for CAS operations
         'watch' => $zsetKey, // Key that needs to be WATCHed to detect changes
         'retry' => 3,        // Number of retries on aborted transactions, after
                              // which the client bails out with an exception.
    );

     $txReply = $client->multiExec($options, function($tx )
         use ($zsetKey, & $element) {
         @ list($element) = $tx->zrange($zsetKey, 0, 0);
         if (isset($element))  {
             $tx->multi();      // With CAS, MULTI *must* be explicitly invoked.
             $tx->zrem($zsetKey, $element);
         }
     });
     return  $element;
}
$zpopped = zpop($redis, 'zset');
echo  isset($zpopped)?  "ZPOPed $zpopped"  :  "Nothing to ZPOP!", "\n";

//对存取的key加前缀,如: 'nrk:'
$redis->getProfile()->setPreprocessor(new KeyPrefixPreprocessor('nrk:'));

//分布式存储的一些方法
$multiple_servers = array (
     array (
        'host'     => '127.0.0.1',
        'port'     => 6379,
        'database' => 15,
        'alias'    => 'first',
    ),
     array (
        'host'     => '127.0.0.1',
        'port'     => 6380,
        'database' => 15,
        'alias'    => 'second',
    ),
);


use Predis\Distribution\IDistributionStrategy;
class NaiveDistributionStrategy implements IDistributionStrategy  {
     private  $_nodes, $_nodesCount;

     public  function __constructor()  {
         $this->_nodes = array();
         $this->_nodesCount = 0;
     }

     public  function add($node, $weight = null) {
         $this->_nodes [ ] = $node;
         $this->_nodesCount ++;
     }

     public  function remove($node) {
         $this->_nodes = array_filter($this->_nodes, function($n) use($node) {
             return  $n  !== $node;
         });
         $this->_nodesCount = count($this->_nodes);
     }

     public  function get($key) {
         $count = $this->_nodesCount;
         if ($count === 0) {
             throw  new RuntimeException('No connections');
         }
         return  $this->_nodes [ $count  >  1 ?  abs(crc32($key) %  $count) :  0 ];
     }

     public  function generateKey($value) {
         return  crc32($value);
     }
}

//配置键分布策略
$options = array (
    'key_distribution' => new NaiveDistributionStrategy(),
);

$redis = new Predis\Client($multiple_servers, $options);

for ($i = 0;  $i set("key:$i", str_pad($i, 4, '0', 0));
    $redis->get("key:$i");
}

$server1 = $redis->getClientFor('first')-> info();
$server2 = $redis->getClientFor('second')-> info();

printf("Server '%s' has %d keys while server '%s' has %d keys.\n",
    'first', $server1 [ 'db15' ] [ 'keys' ], 'second', $server2 [ 'db15' ] [ 'keys' ]
); 

<?php

namespace Illuminate\Redis\Connections;

use Closure;
use Illuminate\Contracts\Redis\Connection as ConnectionContract;
use Illuminate\Support\Str;
use Redis;
use RedisCluster;
use RedisException;

/**
 * @mixin \Redis
 */
class PhpRedisConnection extends Connection implements ConnectionContract
{
    /**
     * The connection creation callback.
     *
     * @var callable
     */
    protected $connector;

    /**
     * Create a new PhpRedis connection.
     *
     * @param  \Redis  $client
     * @param  callable  $connector
     * @return void
     */
    public function __construct($client, callable $connector = null)
    {
        $this->client = $client;
        $this->connector = $connector;
    }

    /**
     * Returns the value of the given key.
     *
     * @param  string  $key
     * @return string|null
     */
    public function get($key)
    {
        $result = $this->command('get', [$key]);

        return $result !== false ? $result : null;
    }

    /**
     * Get the values of all the given keys.
     *
     * @param  array  $keys
     * @return array
     */
    public function mget(array $keys)
    {
        return array_map(function ($value) {
            return $value !== false ? $value : null;
        }, $this->command('mget', [$keys]));
    }

    /**
     * Determine if the given keys exist.
     *
     * @param  mixed  $keys
     * @return int
     */
    public function exists(...$keys)
    {
        $keys = collect($keys)->map(function ($key) {
            return $this->applyPrefix($key);
        })->all();

        return $this->executeRaw(array_merge(['exists'], $keys));
    }

    /**
     * Set the string value in argument as value of the key.
     *
     * @param  string  $key
     * @param  mixed  $value
     * @param  string|null  $expireResolution
     * @param  int|null  $expireTTL
     * @param  string|null  $flag
     * @return bool
     */
    public function set($key, $value, $expireResolution = null, $expireTTL = null, $flag = null)
    {
        return $this->command('set', [
            $key,
            $value,
            $expireResolution ? [$flag, $expireResolution => $expireTTL] : null,
        ]);
    }

    /**
     * Set the given key if it doesn't exist.
     *
     * @param  string  $key
     * @param  string  $value
     * @return int
     */
    public function setnx($key, $value)
    {
        return (int) $this->command('setnx', [$key, $value]);
    }

    /**
     * Get the value of the given hash fields.
     *
     * @param  string  $key
     * @param  mixed  $dictionary
     * @return array
     */
    public function hmget($key, ...$dictionary)
    {
        if (count($dictionary) === 1) {
            $dictionary = $dictionary[0];
        }

        return array_values($this->command('hmget', [$key, $dictionary]));
    }

    /**
     * Set the given hash fields to their respective values.
     *
     * @param  string  $key
     * @param  mixed  $dictionary
     * @return int
     */
    public function hmset($key, ...$dictionary)
    {
        if (count($dictionary) === 1) {
            $dictionary = $dictionary[0];
        } else {
            $input = collect($dictionary);

            $dictionary = $input->nth(2)->combine($input->nth(2, 1))->toArray();
        }

        return $this->command('hmset', [$key, $dictionary]);
    }

    /**
     * Set the given hash field if it doesn't exist.
     *
     * @param  string  $hash
     * @param  string  $key
     * @param  string  $value
     * @return int
     */
    public function hsetnx($hash, $key, $value)
    {
        return (int) $this->command('hsetnx', [$hash, $key, $value]);
    }

    /**
     * Removes the first count occurrences of the value element from the list.
     *
     * @param  string  $key
     * @param  int  $count
     * @param  mixed  $value
     * @return int|false
     */
    public function lrem($key, $count, $value)
    {
        return $this->command('lrem', [$key, $value, $count]);
    }

    /**
     * Removes and returns the first element of the list stored at key.
     *
     * @param  mixed  $arguments
     * @return array|null
     */
    public function blpop(...$arguments)
    {
        $result = $this->command('blpop', $arguments);

        return empty($result) ? null : $result;
    }

    /**
     * Removes and returns the last element of the list stored at key.
     *
     * @param  mixed  $arguments
     * @return array|null
     */
    public function brpop(...$arguments)
    {
        $result = $this->command('brpop', $arguments);

        return empty($result) ? null : $result;
    }

    /**
     * Removes and returns a random element from the set value at key.
     *
     * @param  string  $key
     * @param  int|null  $count
     * @return mixed|false
     */
    public function spop($key, $count = 1)
    {
        return $this->command('spop', [$key, $count]);
    }

    /**
     * Add one or more members to a sorted set or update its score if it already exists.
     *
     * @param  string  $key
     * @param  mixed  $dictionary
     * @return int
     */
    public function zadd($key, ...$dictionary)
    {
        if (is_array(end($dictionary))) {
            foreach (array_pop($dictionary) as $member => $score) {
                $dictionary[] = $score;
                $dictionary[] = $member;
            }
        }

        $key = $this->applyPrefix($key);

        return $this->executeRaw(array_merge(['zadd', $key], $dictionary));
    }

    /**
     * Return elements with score between $min and $max.
     *
     * @param  string  $key
     * @param  mixed  $min
     * @param  mixed  $max
     * @param  array  $options
     * @return array
     */
    public function zrangebyscore($key, $min, $max, $options = [])
    {
        if (isset($options['limit'])) {
            $options['limit'] = [
                $options['limit']['offset'],
                $options['limit']['count'],
            ];
        }

        return $this->command('zRangeByScore', [$key, $min, $max, $options]);
    }

    /**
     * Return elements with score between $min and $max.
     *
     * @param  string  $key
     * @param  mixed  $min
     * @param  mixed  $max
     * @param  array  $options
     * @return array
     */
    public function zrevrangebyscore($key, $min, $max, $options = [])
    {
        if (isset($options['limit'])) {
            $options['limit'] = [
                $options['limit']['offset'],
                $options['limit']['count'],
            ];
        }

        return $this->command('zRevRangeByScore', [$key, $min, $max, $options]);
    }

    /**
     * Find the intersection between sets and store in a new set.
     *
     * @param  string  $output
     * @param  array  $keys
     * @param  array  $options
     * @return int
     */
    public function zinterstore($output, $keys, $options = [])
    {
        return $this->command('zinterstore', [$output, $keys,
            $options['weights'] ?? null,
            $options['aggregate'] ?? 'sum',
        ]);
    }

    /**
     * Find the union between sets and store in a new set.
     *
     * @param  string  $output
     * @param  array  $keys
     * @param  array  $options
     * @return int
     */
    public function zunionstore($output, $keys, $options = [])
    {
        return $this->command('zunionstore', [$output, $keys,
            $options['weights'] ?? null,
            $options['aggregate'] ?? 'sum',
        ]);
    }

    /**
     * Execute commands in a pipeline.
     *
     * @param  callable|null  $callback
     * @return \Redis|array
     */
    public function pipeline(callable $callback = null)
    {
        $pipeline = $this->client()->pipeline();

        return is_null($callback)
            ? $pipeline
            : tap($pipeline, $callback)->exec();
    }

    /**
     * Execute commands in a transaction.
     *
     * @param  callable|null  $callback
     * @return \Redis|array
     */
    public function transaction(callable $callback = null)
    {
        $transaction = $this->client()->multi();

        return is_null($callback)
            ? $transaction
            : tap($transaction, $callback)->exec();
    }

    /**
     * Evaluate a LUA script serverside, from the SHA1 hash of the script instead of the script itself.
     *
     * @param  string  $script
     * @param  int  $numkeys
     * @param  mixed  $arguments
     * @return mixed
     */
    public function evalsha($script, $numkeys, ...$arguments)
    {
        return $this->command('evalsha', [
            $this->script('load', $script), $arguments, $numkeys,
        ]);
    }

    /**
     * Evaluate a script and return its result.
     *
     * @param  string  $script
     * @param  int  $numberOfKeys
     * @param  dynamic  $arguments
     * @return mixed
     */
    public function eval($script, $numberOfKeys, ...$arguments)
    {
        return $this->command('eval', [$script, $arguments, $numberOfKeys]);
    }

    /**
     * Subscribe to a set of given channels for messages.
     *
     * @param  array|string  $channels
     * @param  \Closure  $callback
     * @return void
     */
    public function subscribe($channels, Closure $callback)
    {
        $this->client->subscribe((array) $channels, function ($redis, $channel, $message) use ($callback) {
            $callback($message, $channel);
        });
    }

    /**
     * Subscribe to a set of given channels with wildcards.
     *
     * @param  array|string  $channels
     * @param  \Closure  $callback
     * @return void
     */
    public function psubscribe($channels, Closure $callback)
    {
        $this->client->psubscribe((array) $channels, function ($redis, $pattern, $channel, $message) use ($callback) {
            $callback($message, $channel);
        });
    }

    /**
     * Subscribe to a set of given channels for messages.
     *
     * @param  array|string  $channels
     * @param  \Closure  $callback
     * @param  string  $method
     * @return void
     */
    public function createSubscription($channels, Closure $callback, $method = 'subscribe')
    {
        //
    }

    /**
     * Flush the selected Redis database.
     *
     * @return void
     */
    public function flushdb()
    {
        if (! $this->client instanceof RedisCluster) {
            return $this->command('flushdb');
        }

        foreach ($this->client->_masters() as [$host, $port]) {
            tap(new Redis)->connect($host, $port)->flushDb();
        }
    }

    /**
     * Execute a raw command.
     *
     * @param  array  $parameters
     * @return mixed
     */
    public function executeRaw(array $parameters)
    {
        return $this->command('rawCommand', $parameters);
    }

    /**
     * Run a command against the Redis database.
     *
     * @param  string  $method
     * @param  array  $parameters
     * @return mixed
     */
    public function command($method, array $parameters = [])
    {
        try {
            return parent::command($method, $parameters);
        } catch (RedisException $e) {
            if (Str::contains($e->getMessage(), 'went away')) {
                $this->client = $this->connector ? call_user_func($this->connector) : $this->client;
            }

            throw $e;
        }
    }

    /**
     * Disconnects from the Redis instance.
     *
     * @return void
     */
    public function disconnect()
    {
        $this->client->close();
    }

    /**
     * Apply prefix to the given key if necessary.
     *
     * @param  string  $key
     * @return string
     */
    private function applyPrefix($key)
    {
        $prefix = (string) $this->client->getOption(Redis::OPT_PREFIX);

        return $prefix.$key;
    }

    /**
     * Pass other method calls down to the underlying client.
     *
     * @param  string  $method
     * @param  array  $parameters
     * @return mixed
     */
    public function __call($method, $parameters)
    {
        return parent::__call(strtolower($method), $parameters);
    }
}