今天在开发备件库存时遇到需要为每一个设备生成一个唯一的traceID,用于对设备的来龙去脉进行跟踪。同时为了检索方便就在网上搜了一下,没想到竟然在PHP的函数uniqid()下面看到了一个PHP生成唯一UUID的方法。
所以转载收藏一下,以供不时之需。
类库介绍:
The following class generates VALID RFC 4211 COMPLIANT Universally Unique IDentifiers (UUID) version 3, 4 and 5.
Version 3 and 5 UUIDs are named based. They require a namespace (another valid UUID) and a value (the name). Given the same namespace and name, the output is always the same.
Version 4 UUIDs are pseudo-random.
UUIDs generated below validates using OSSP UUID Tool, and output for named-based UUIDs are exactly the same. This is a pure PHP implementation.
类库源码:
- <?php
- class UUID {
- public static function v3($namespace, $name) {
- if(!self::is_valid($namespace)) return false;
- // Get hexadecimal components of namespace
- $nhex = str_replace(array('-','{','}'), '', $namespace);
- // Binary Value
- $nstr = '';
- // Convert Namespace UUID to bits
- for($i = 0; $i < strlen($nhex); $i+=2) {
- $nstr .= chr(hexdec($nhex[$i].$nhex[$i+1]));
- }
- // Calculate hash value
- $hash = md5($nstr . $name);
- return sprintf('%08s-%04s-%04x-%04x-%12s',
- // 32 bits for "time_low"
- substr($hash, 0, 8),
- // 16 bits for "time_mid"
- substr($hash, 8, 4),
- // 16 bits for "time_hi_and_version",
- // four most significant bits holds version number 3
- (hexdec(substr($hash, 12, 4)) & 0x0fff) | 0x3000,
- // 16 bits, 8 bits for "clk_seq_hi_res",
- // 8 bits for "clk_seq_low",
- // two most significant bits holds zero and one for variant DCE1.1
- (hexdec(substr($hash, 16, 4)) & 0x3fff) | 0x8000,
- // 48 bits for "node"
- substr($hash, 20, 12)
- );
- }
- public static function v4() {
- return sprintf('%04x%04x-%04x-%04x-%04x-%04x%04x%04x',
- // 32 bits for "time_low"
- mt_rand(0, 0xffff), mt_rand(0, 0xffff),
- // 16 bits for "time_mid"
- mt_rand(0, 0xffff),
- // 16 bits for "time_hi_and_version",
- // four most significant bits holds version number 4
- mt_rand(0, 0x0fff) | 0x4000,
- // 16 bits, 8 bits for "clk_seq_hi_res",
- // 8 bits for "clk_seq_low",
- // two most significant bits holds zero and one for variant DCE1.1
- mt_rand(0, 0x3fff) | 0x8000,
- // 48 bits for "node"
- mt_rand(0, 0xffff), mt_rand(0, 0xffff), mt_rand(0, 0xffff)
- );
- }
- public static function v5($namespace, $name) {
- if(!self::is_valid($namespace)) return false;
- // Get hexadecimal components of namespace
- $nhex = str_replace(array('-','{','}'), '', $namespace);
- // Binary Value
- $nstr = '';
- // Convert Namespace UUID to bits
- for($i = 0; $i < strlen($nhex); $i+=2) {
- $nstr .= chr(hexdec($nhex[$i].$nhex[$i+1]));
- }
- // Calculate hash value
- $hash = sha1($nstr . $name);
- return sprintf('%08s-%04s-%04x-%04x-%12s',
- // 32 bits for "time_low"
- substr($hash, 0, 8),
- // 16 bits for "time_mid"
- substr($hash, 8, 4),
- // 16 bits for "time_hi_and_version",
- // four most significant bits holds version number 5
- (hexdec(substr($hash, 12, 4)) & 0x0fff) | 0x5000,
- // 16 bits, 8 bits for "clk_seq_hi_res",
- // 8 bits for "clk_seq_low",
- // two most significant bits holds zero and one for variant DCE1.1
- (hexdec(substr($hash, 16, 4)) & 0x3fff) | 0x8000,
- // 48 bits for "node"
- substr($hash, 20, 12)
- );
- }
- public static function is_valid($uuid) {
- return preg_match('/^\{?[0-9a-f]{8}\-?[0-9a-f]{4}\-?[0-9a-f]{4}\-?'.
- '[0-9a-f]{4}\-?[0-9a-f]{12}\}?$/i', $uuid) === 1;
- }
- }
- // Usage
- // Named-based UUID.
- $v3uuid = UUID::v3('1546058f-5a25-4334-85ae-e68f2a44bbaf', 'SomeRandomString');
- $v5uuid = UUID::v5('1546058f-5a25-4334-85ae-e68f2a44bbaf', 'SomeRandomString');
- // Pseudo-random UUID
- $v4uuid = UUID::v4();
- ?>
这东西完全是意外收获哈。