php中通过Hashids将整数转化为唯一字符串
这个类主要是前台显示的主键ID转化成一串无规律的字符串，比较像 Youtube、Youku、Weibo之类的 id 名，从某种意义上可以防采集
在项目中，暴露给用户真实的项目ID，很有可能被恶意采集，很有可能被猜到目前有多少量（对造假不利）。
<?php /* Hashids http://hashids.org/php (c) 2013 Ivan Akimov https://github.com/ivanakimov/hashids.php hashids may be freely distributed under the MIT license. */ /** * HashGenerator is a contract for generating hashes */ interface HashGenerator { /** * Encodes a variable number of parameters to generate a hash * * @param mixed ... * * @return string the generated hash */ public function encode(); /** * Decodes a hash to the original parameter values * * @param string $hash the hash to decode * * @return array */ public function decode($hash); /** * Encodes hexadecimal values to generate a hash * * @param string $str hexadecimal string * * @return string the generated hash */ public function encode_hex($str); /** * Decodes hexadecimal hash * * @param string $hash * * @return string hexadecimal string */ public function decode_hex($hash); } class Hashids implements HashGenerator { const VERSION = '1.0.5'; /* internal settings */ const MIN_ALPHABET_LENGTH = 16; const SEP_DIV = 3.5; const GUARD_DIV = 12; /* error messages */ const E_ALPHABET_LENGTH = 'alphabet must contain at least %d unique characters'; const E_ALPHABET_SPACE = 'alphabet cannot contain spaces'; /* set at constructor */ private $_alphabet = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890'; private $_seps = 'cfhistuCFHISTU'; private $_min_hash_length = 0; private $_math_functions = array(); private $_max_int_value = 1000000000; const hashids_length = 6; // 加密字符串长度 const hashids_salt = 'test'; // 加密钥匙 const hashids_alphabet = ''; // 字符仓库,不填写默认为扩展里的字符仓库 private static $instance; //单例 /** * 初始化 * @param array $options * @return static */ public static function instance($length = null, $salt = null, $alphabet = null) { if (is_null(self::$instance)) { if ($length === null) $length = self::hashids_length; if ($salt === null) $salt = self::hashids_salt; if ($alphabet === null) self::hashids_alphabet; self::$instance = new static($salt, $length, $alphabet); } return self::$instance; } public function __construct($salt = '', $min_hash_length = 8, $alphabet = '') { /* if either math precision library is present, raise $this->_max_int_value */ if (function_exists('gmp_add')) { $this->_math_functions['add'] = 'gmp_add'; $this->_math_functions['div'] = 'gmp_div'; $this->_math_functions['str'] = 'gmp_strval'; } else if (function_exists('bcadd')) { $this->_math_functions['add'] = 'bcadd'; $this->_math_functions['div'] = 'bcdiv'; $this->_math_functions['str'] = 'strval'; } $this->_lower_max_int_value = $this->_max_int_value; if ($this->_math_functions) { $this->_max_int_value = PHP_INT_MAX; } /* handle parameters */ $this->_salt = $salt; if ((int)$min_hash_length > 0) { $this->_min_hash_length = (int)$min_hash_length; } if ($alphabet) { $this->_alphabet = implode('', array_unique(str_split($alphabet))); } if (strlen($this->_alphabet) < self::MIN_ALPHABET_LENGTH) { throw new \Exception(sprintf(self::E_ALPHABET_LENGTH, self::MIN_ALPHABET_LENGTH)); } if (is_int(strpos($this->_alphabet, ' '))) { throw new \Exception(self::E_ALPHABET_SPACE); } $alphabet_array = str_split($this->_alphabet); $seps_array = str_split($this->_seps); $this->_seps = implode('', array_intersect($alphabet_array, $seps_array)); $this->_alphabet = implode('', array_diff($alphabet_array, $seps_array)); $this->_seps = $this->_consistent_shuffle($this->_seps, $this->_salt); if (!$this->_seps || (strlen($this->_alphabet) / strlen($this->_seps)) > self::SEP_DIV) { $seps_length = (int)ceil(strlen($this->_alphabet) / self::SEP_DIV); if ($seps_length == 1) { $seps_length++; } if ($seps_length > strlen($this->_seps)) { $diff = $seps_length - strlen($this->_seps); $this->_seps .= substr($this->_alphabet, 0, $diff); $this->_alphabet = substr($this->_alphabet, $diff); } else { $this->_seps = substr($this->_seps, 0, $seps_length); } } $this->_alphabet = $this->_consistent_shuffle($this->_alphabet, $this->_salt); $guard_count = (int)ceil(strlen($this->_alphabet) / self::GUARD_DIV); if (strlen($this->_alphabet) < 3) { $this->_guards = substr($this->_seps, 0, $guard_count); $this->_seps = substr($this->_seps, $guard_count); } else { $this->_guards = substr($this->_alphabet, 0, $guard_count); $this->_alphabet = substr($this->_alphabet, $guard_count); } } public function encode() { $ret = ''; $numbers = func_get_args(); if (func_num_args() == 1 && is_array(func_get_arg(0))) { $numbers = $numbers[0]; } if (!$numbers) { return $ret; } foreach ($numbers as $number) { $is_number = ctype_digit((string)$number); if (!$is_number || $number < 0 || $number > $this->_max_int_value) { return $ret; } } return $this->_encode($numbers); } public function decode($hash) { $ret = array(); if (!$hash || !is_string($hash) || !trim($hash)) { return $ret; } return $this->_decode(trim($hash), $this->_alphabet); } public function encode_hex($str) { if (!ctype_xdigit((string)$str)) { return ''; } $numbers = trim(chunk_split($str, 12, ' ')); $numbers = explode(' ', $numbers); foreach ($numbers as $i => $number) { $numbers[$i] = hexdec('1' . $number); } return call_user_func_array(array($this, 'encode'), $numbers); } public function decode_hex($hash) { $ret = ""; $numbers = $this->decode($hash); foreach ($numbers as $i => $number) { $ret .= substr(dechex($number), 1); } return $ret; } public function get_max_int_value() { return $this->_max_int_value; } private function _encode(array $numbers) { $alphabet = $this->_alphabet; $numbers_size = sizeof($numbers); $numbers_hash_int = 0; foreach ($numbers as $i => $number) { $numbers_hash_int += ($number % ($i + 100)); } $lottery = $ret = $alphabet[$numbers_hash_int % strlen($alphabet)]; foreach ($numbers as $i => $number) { $alphabet = $this->_consistent_shuffle($alphabet, substr($lottery . $this->_salt . $alphabet, 0, strlen($alphabet))); $ret .= $last = $this->_hash($number, $alphabet); if ($i + 1 < $numbers_size) { $number %= (ord($last) + $i); $seps_index = $number % strlen($this->_seps); $ret .= $this->_seps[$seps_index]; } } if (strlen($ret) < $this->_min_hash_length) { $guard_index = ($numbers_hash_int + ord($ret[0])) % strlen($this->_guards); $guard = $this->_guards[$guard_index]; $ret = $guard . $ret; if (strlen($ret) < $this->_min_hash_length) { $guard_index = ($numbers_hash_int + ord($ret[2])) % strlen($this->_guards); $guard = $this->_guards[$guard_index]; $ret .= $guard; } } $half_length = (int)(strlen($alphabet) / 2); while (strlen($ret) < $this->_min_hash_length) { $alphabet = $this->_consistent_shuffle($alphabet, $alphabet); $ret = substr($alphabet, $half_length) . $ret . substr($alphabet, 0, $half_length); $excess = strlen($ret) - $this->_min_hash_length; if ($excess > 0) { $ret = substr($ret, $excess / 2, $this->_min_hash_length); } } return $ret; } private function _decode($hash, $alphabet) { $ret = array(); $hash_breakdown = str_replace(str_split($this->_guards), ' ', $hash); $hash_array = explode(' ', $hash_breakdown); $i = 0; if (sizeof($hash_array) == 3 || sizeof($hash_array) == 2) { $i = 1; } $hash_breakdown = $hash_array[$i]; if (isset($hash_breakdown[0])) { $lottery = $hash_breakdown[0]; $hash_breakdown = substr($hash_breakdown, 1); $hash_breakdown = str_replace(str_split($this->_seps), ' ', $hash_breakdown); $hash_array = explode(' ', $hash_breakdown); foreach ($hash_array as $sub_hash) { $alphabet = $this->_consistent_shuffle($alphabet, substr($lottery . $this->_salt . $alphabet, 0, strlen($alphabet))); $ret[] = (int)$this->_unhash($sub_hash, $alphabet); } if ($this->_encode($ret) != $hash) { $ret = array(); } } //修改为直接返回字符串 if(isset($ret[0])){ return $ret[0]; }else{ return false; } } private function _consistent_shuffle($alphabet, $salt) { if (!strlen($salt)) { return $alphabet; } for ($i = strlen($alphabet) - 1, $v = 0, $p = 0; $i > 0; $i--, $v++) { $v %= strlen($salt); $p += $int = ord($salt[$v]); $j = ($int + $v + $p) % $i; $temp = $alphabet[$j]; $alphabet[$j] = $alphabet[$i]; $alphabet[$i] = $temp; } return $alphabet; } private function _hash($input, $alphabet) { $hash = ''; $alphabet_length = strlen($alphabet); do { $hash = $alphabet[$input % $alphabet_length] . $hash; if ($input > $this->_lower_max_int_value && $this->_math_functions) { $input = $this->_math_functions['str']($this->_math_functions['div']($input, $alphabet_length)); } else { $input = (int)($input / $alphabet_length); } } while ($input); return $hash; } private function _unhash($input, $alphabet) { $number = 0; if (strlen($input) && $alphabet) { $alphabet_length = strlen($alphabet); $input_chars = str_split($input); foreach ($input_chars as $i => $char) { $pos = strpos($alphabet, $char); if ($this->_math_functions) { $number = $this->_math_functions['str']($this->_math_functions['add']($number, $pos * pow($alphabet_length, (strlen($input) - $i - 1)))); } else { $number += $pos * pow($alphabet_length, (strlen($input) - $i - 1)); } } } return $number; } }
调用Hashids类进行加密解密ID
$user_id = 11; $hashids = Hashids::instance(8,'test11'); $encode_id = $hashids->encode($user_id); //加密 echo '<pre>'; var_dump($encode_id).PHP_EOL; $decode_id = $hashids->decode($encode_id); //解密 echo '<pre>'; var_dump($decode_id).PHP_EOL; exit();
