redis是一个开源的使用ansi c语言编写、支持网络、可基于内存亦可持久化的日志型、key-value数据库，并提供多种语言的api。
这里使用其incr(自增)，get(获取)，delete(清除)方法来实现计数器类。本文主要和大家介绍了PHP基于redis计数器类定义与用法,结合实例形式较为详细的分析了php定义的redis计数器类及其相关使用技巧,需要的朋友可以参考下，希望能帮助到大家。
1.Redis计数器类代码及演示实例
RedisCounter.class.php
_config = $config;
$this->_redis = $this->connect();
}
/**
* 执行自增计数并获取自增后的数值
* @param String $key 保存计数的键值
* @param Int $incr 自增数量，默认为1
* @return Int
*/
public function incr($key, $incr=1){
return intval($this->_redis->incr($key, $incr));
}
/**
* 获取当前计数
* @param String $key 保存计数的健值
* @return Int
*/
public function get($key){
return intval($this->_redis->get($key));
}
/**
* 重置计数
* @param String $key 保存计数的健值
* @return Int
*/
public function reset($key){
return $this->_redis->delete($key);
}
/**
* 创建redis连接
* @return Link
*/
private function connect(){
try{
$redis = new Redis();
$redis->connect($this->_config['host'],$this->_config['port'],$this->_config['timeout'],$this->_config['reserved'],$this->_config['retry_interval']);
if(empty($this->_config['auth'])){
$redis->auth($this->_config['auth']);
}
$redis->select($this->_config['index']);
}catch(RedisException $e){
throw new Exception($e->getMessage());
return false;
}
return $redis;
}
} // class end
?>demo.php
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'localhost', 'port' => 6379, 'index' => 0, 'auth' => '', 'timeout' => 1, 'reserved' => NULL, 'retry_interval' => 100, ); // 创建RedisCounter对象 $oRedisCounter = new RedisCounter($config); // 定义保存计数的健值 $key = 'mycounter'; // 执行自增计数，获取当前计数，重置计数 echo $oRedisCounter->get($key).PHP_EOL; // 0 echo $oRedisCounter->incr($key).PHP_EOL; // 1 echo $oRedisCounter->incr($key, 10).PHP_EOL; // 11 echo $oRedisCounter->reset($key).PHP_EOL; // 1 echo $oRedisCounter->get($key).PHP_EOL; // 0 ?>
输出：
0 1 11 1 0
2.并发调用计数器，检查计数唯一性
测试代码如下：
'localhost',
'port' => 6379,
'index' => 0,
'auth' => '',
'timeout' => 1,
'reserved' => NULL,
'retry_interval' => 100,
);
// 创建RedisCounter对象
$oRedisCounter = new RedisCounter($config);
// 定义保存计数的健值
$key = 'mytestcounter';
// 执行自增计数并返回自增后的计数，记录入临时文件
file_put_contents('/tmp/mytest_result.log', $oRedisCounter->incr($key).PHP_EOL, FILE_APPEND);
?>测试并发执行，我们使用ab工具进行测试，设置执行150次，15个并发。
ab -c 15 -n 150 http://localhost/test.php
执行结果：
ab -c 15 -n 150 http://localhost/test.php
This is ApacheBench, Version 2.3 <$Revision: 1554214 $>
Copyright 1996 Adam Twiss, Zeus Technology Ltd, http://www.zeustech.net/
Licensed to The Apache Software Foundation, http://www.apache.org/
Benchmarking home.rabbit.km.com (be patient).....done
Server Software: nginx/1.6.3
Server Hostname: localhost
Server Port: 80
Document Path: /test.php
Document Length: 0 bytes
Concurrency Level: 15
Time taken for tests: 0.173 seconds
Complete requests: 150
Failed requests: 0
Total transferred: 24150 bytes
HTML transferred: 0 bytes
Requests per second: 864.86 [#/sec] (mean)
Time per request: 17.344 [ms] (mean)
Time per request: 1.156 [ms] (mean, across all concurrent requests)
Transfer rate: 135.98 [Kbytes/sec] received
Connection Times (ms)
min mean[+/-sd] median max
Connect: 0 0 0.2 0 1
Processing: 3 16 3.2 16 23
Waiting: 3 16 3.2 16 23
Total: 4 16 3.1 17 23
Percentage of the requests served within a certain time (ms)
50% 17
66% 18
75% 18
80% 19
90% 20
95% 21
98% 22
99% 22
100% 23 (longest request)检查计数是否唯一
生成的总计数 wc -l /tmp/mytest_result.log 150 /tmp/mytest_result.log 生成的唯一计数 sort -u /tmp/mytest_result.log | wc -l 150
可以看到在并发调用的情况下，生成的计数也保证唯一。
