<?php /** * 全局唯一id生产类 * https://segmentfault.com/a/1190000007769660 * 基于Twitter的SnowFlake算法改造 * twitter的结构: * 64bit = 1bit为空缺 + 41bit毫秒时间戳 + 10bit机器id + 12bit自增id * 当前结构 **** 最多支持128项业务 * 64bit = 1bit空缺 + 7bit业务编号(128项业务) + 39bit毫秒时间戳(与2017-06-01的差值) + 5bit机器id(32台) + 4bit一级随机数 + 4bit二级随机数 + 4bit三级随机数 */ $machineid_file = "/data/machineid.txt"; if (file_exists($machineid_file)) { $machine_id = intval(file_get_contents($machineid_file)); if ($machine_id > 31 || $machine_id < 0) { $machine_id = 0; } } else { $machine_id = 0; } define('MACHINE_ID', $machine_id); class BusinessIdHelper { public static $start_stamp = 1496246400000; // 2017-06-01 00:00:00的毫秒级时间戳 public static $max_rand = 15; public static function generateId($business_id) { // 1bit - 头部空缺 $head_bin = str_pad(decbin(0), 1, "0", STR_PAD_LEFT); // 7bit - 7bit业务编号(最多128项业务) $business_id_bin = str_pad(decbin($business_id), 7, "0", STR_PAD_LEFT); // 39bit - (now - $start_stamp)的毫秒级时间戳差值 $now_stamp = floor(microtime(true) * 1000); $diff_stamp_bin = str_pad(decbin($now_stamp - self::$start_stamp), 39, "0", STR_PAD_LEFT); // 5bit - 32台机器 $machine_id_bin = str_pad(decbin(MACHINE_ID), 5, "0", STR_PAD_LEFT); // 4bit - 4位随机数(0 ~ 15) // 一级 $random1 = mt_rand(0, self::$max_rand); $random1_bin = str_pad(decbin($random1), 4, "0", STR_PAD_LEFT); // 二级 $random2 = mt_rand(0, self::$max_rand); $random2_bin = str_pad(decbin($random2), 4, "0", STR_PAD_LEFT); // 三级 $random3 = mt_rand(0, self::$max_rand); $random3_bin = str_pad(decbin($random3), 4, "0", STR_PAD_LEFT); // 链接二进制串 $pack_data = $head_bin . $business_id_bin . $diff_stamp_bin . $machine_id_bin . $random1_bin . $random2_bin . $random3_bin; /* var_dump($business_id); var_dump($now_stamp); var_dump(MACHINE_ID); var_dump($pid); var_dump($pack_data); */ return bindec($pack_data); } public static function parseId($id) { // 数据不满64位的,需要补齐 $data_bin = str_pad(decbin($id), 64, "0", STR_PAD_LEFT); $head_bin = substr($data_bin, 0, 1); $business_id_bin = substr($data_bin, 1, 7); $diff_stamp_bin = substr($data_bin, 8, 39); $machine_id_bin = substr($data_bin, 47, 5); $random1_bin = substr($data_bin, 52, 4); $random2_bin = substr($data_bin, 56, 4); $random3_bin = substr($data_bin, 60, 4); $head = bindec($head_bin); $business_id = bindec($business_id_bin); $diff_stamp = bindec($diff_stamp_bin); $machine_id = bindec($machine_id_bin); $random1 = bindec($random1_bin); $random2 = bindec($random2_bin); $random3 = bindec($random3_bin); $stamp = self::$start_stamp + $diff_stamp; // 毫秒 $data = [ 'head' => $head, 'business_id' => $business_id, 'stamp' => $stamp, // 毫秒 'machine_id' => $machine_id, 'random1' => $random1, 'random2' => $random2, 'random3' => $random3, ]; return $data; } } ?>