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。
本文将使用其incr(自增)，get(获取)，delete(清除)方法来实现计数器类。
1.redis计数器类代码及演示实例rediscounter.class.php
<?php/** * php基于redis计数器类 * date: 2017-10-28 * author: fdipzone * version: 1.0 * * descripton: * php基于redis实现自增计数，主要使用redis的incr方法，并发执行时保证计数自增唯一。 * * func: * public incr 执行自增计数并获取自增后的数值 * public get 获取当前计数 * public reset 重置计数 * private connect 创建redis连接 */class rediscounter{ // class start private $_config; private $_redis; /** * 初始化 * @param array $config redis连接设定 */ public function __construct($config){ $this->_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 $redis; }} // class end?>
demo.php
<?phprequire 'rediscounter.class.php';// redis连接设定$config = array( 'host' => '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; // 0echo $orediscounter->incr($key).php_eol; // 1echo $orediscounter->incr($key, 10).php_eol; // 11echo $orediscounter->reset($key).php_eol; // 1echo $orediscounter->get($key).php_eol; // 0 ?>
输出：
011110
2.并发调用计数器，检查计数唯一性
测试代码如下：
<?phprequire 'rediscounter.class.php';// redis连接设定$config = array( 'host' => 'localhost', 'port' => 6379, 'index' => 0, 'auth' => '', 'timeout' => 1, 'reserved' => null, 'retry_interval' => 100,);// 创建rediscounter对象$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.phpthis 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).....doneserver software: nginx/1.6.3server hostname: localhostserver port: 80document path: /test.phpdocument length: 0 bytesconcurrency level: 15time taken for tests: 0.173 secondscomplete requests: 150failed requests: 0total transferred: 24150 byteshtml transferred: 0 bytesrequests 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] receivedconnection times (ms) min mean[+/-sd] median maxconnect: 0 0 0.2 0 1processing: 3 16 3.2 16 23waiting: 3 16 3.2 16 23total: 4 16 3.1 17 23percentage 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。
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以上就是一分钟解读php基于redis计数器类的详细内容。