使用 JavaScript.. 的 md5 的较短版本？
Shorter version of md5 using JavaScript..?
我在 JSON 文件中有 array 个 object。 object 没有唯一的 id，所以我需要创建一个唯一的 id 或唯一的 string.
[
{
"name": "Jack Potts",
"age": "56"
}, {
"name": "Rusty Carr",
"age": "31"
}
]
我知道我可以使用 MD5，传入 object，但我要在 URL 中使用 string，所以我会希望它更短。
而不是 /people/3449c9e5e332f1dbb81505cd739fbf3f，我更喜欢 /people/1dbb81505。
它仍然需要代表 object，因为我要从 URL 中再次查找此人。
是否有任何生成 string 比 MD5 string.. 短的东西？
我猜测 MD5 是我的 best/only 选项，但我想我会问。
更新
我可能不够清楚。我不只是需要生成一个唯一的 id。我不会用我生成的任何内容更新 JSON 文件。
我需要一种方法来获取有问题的 object，为它创建一个 URL，然后在访问 URL 时使用 URL 返回array.
中的 object
据我所知，如果你一遍又一遍地将相同的 string 传递给 MD5，它总是 return 相同的 MD5 string 因为它是表示。出于同样的原因，人们在数据库中存储密码时不使用它吗？
也许 MD5 没问题，我只是想可能有一些东西可以产生更短的 string，这是数据的 表示 。这是我的问题。
更新 2
array 中的人可能会改变。可能会添加和删除人员，因此使用 array 索引将不起作用。
使用以下函数：
function generateUID() {
var firstPart = (Math.random() * 46656) | 0;
var secondPart = (Math.random() * 46656) | 0;
firstPart = ("000" + firstPart.toString(36)).slice(-3);
secondPart = ("000" + secondPart.toString(36)).slice(-3);
return firstPart + secondPart;
}
一个 6 个字符的字母数字序列足以随机索引 10k 的集合（366 = 22 亿，363 = 46656）。
我建议你使用sha1，它处理的散列相对较短。假设您的数据集相对有限 < 1000000000000...等等...项目发生冲突的可能性应该很小。
https://github.com/emn178/js-sha1 是一个不错的图书馆
编辑修改它以使其更短
它现在做了一个子字符串，+ 一个应该可靠的碰撞检测修改，只要项目的顺序在具有 smae 值的情况下不会改变。但话又说回来，如果它们具有相同的值，那应该无关紧要;-)
/*
* [js-sha1]{@link https://github.com/emn178/js-sha1}
*
* @version 0.4.1
* @author Chen, Yi-Cyuan [emn178@gmail.com]
* @copyright Chen, Yi-Cyuan 2014-2016
* @license MIT
*/
/*jslint bitwise: true */
(function() {
'use strict';
var root = typeof window === 'object' ? window : {};
var NODE_JS = !root.JS_SHA1_NO_NODE_JS && typeof process === 'object' && process.versions && process.versions.node;
if (NODE_JS) {
root = global;
}
var COMMON_JS = !root.JS_SHA1_NO_COMMON_JS && typeof module === 'object' && module.exports;
var AMD = typeof define === 'function' && define.amd;
var HEX_CHARS = '0123456789abcdef'.split('');
var EXTRA = [-2147483648, 8388608, 32768, 128];
var SHIFT = [24, 16, 8, 0];
var OUTPUT_TYPES = ['hex', 'array', 'digest', 'arrayBuffer'];
var blocks = [];
var createOutputMethod = function (outputType) {
return function (message) {
return new Sha1(true).update(message)[outputType]();
};
};
var createMethod = function () {
var method = createOutputMethod('hex');
if (NODE_JS) {
method = nodeWrap(method);
}
method.create = function () {
return new Sha1();
};
method.update = function (message) {
return method.create().update(message);
};
for (var i = 0; i < OUTPUT_TYPES.length; ++i) {
var type = OUTPUT_TYPES[i];
method[type] = createOutputMethod(type);
}
return method;
};
var nodeWrap = function (method) {
var crypto = require('crypto');
var Buffer = require('buffer').Buffer;
var nodeMethod = function (message) {
if (typeof message === 'string') {
return crypto.createHash('sha1').update(message, 'utf8').digest('hex');
} else if (message.constructor === ArrayBuffer) {
message = new Uint8Array(message);
} else if (message.length === undefined) {
return method(message);
}
return crypto.createHash('sha1').update(new Buffer(message)).digest('hex');
};
return nodeMethod;
};
function Sha1(sharedMemory) {
if (sharedMemory) {
blocks[0] = blocks[16] = blocks[1] = blocks[2] = blocks[3] =
blocks[4] = blocks[5] = blocks[6] = blocks[7] =
blocks[8] = blocks[9] = blocks[10] = blocks[11] =
blocks[12] = blocks[13] = blocks[14] = blocks[15] = 0;
this.blocks = blocks;
} else {
this.blocks = [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0];
}
this.h0 = 0x67452301;
this.h1 = 0xEFCDAB89;
this.h2 = 0x98BADCFE;
this.h3 = 0x10325476;
this.h4 = 0xC3D2E1F0;
this.block = this.start = this.bytes = 0;
this.finalized = this.hashed = false;
this.first = true;
}
Sha1.prototype.update = function (message) {
if (this.finalized) {
return;
}
var notString = typeof(message) !== 'string';
if (notString && message.constructor === root.ArrayBuffer) {
message = new Uint8Array(message);
}
var code, index = 0, i, length = message.length || 0, blocks = this.blocks;
while (index < length) {
if (this.hashed) {
this.hashed = false;
blocks[0] = this.block;
blocks[16] = blocks[1] = blocks[2] = blocks[3] =
blocks[4] = blocks[5] = blocks[6] = blocks[7] =
blocks[8] = blocks[9] = blocks[10] = blocks[11] =
blocks[12] = blocks[13] = blocks[14] = blocks[15] = 0;
}
if(notString) {
for (i = this.start; index < length && i < 64; ++index) {
blocks[i >> 2] |= message[index] << SHIFT[i++ & 3];
}
} else {
for (i = this.start; index < length && i < 64; ++index) {
code = message.charCodeAt(index);
if (code < 0x80) {
blocks[i >> 2] |= code << SHIFT[i++ & 3];
} else if (code < 0x800) {
blocks[i >> 2] |= (0xc0 | (code >> 6)) << SHIFT[i++ & 3];
blocks[i >> 2] |= (0x80 | (code & 0x3f)) << SHIFT[i++ & 3];
} else if (code < 0xd800 || code >= 0xe000) {
blocks[i >> 2] |= (0xe0 | (code >> 12)) << SHIFT[i++ & 3];
blocks[i >> 2] |= (0x80 | ((code >> 6) & 0x3f)) << SHIFT[i++ & 3];
blocks[i >> 2] |= (0x80 | (code & 0x3f)) << SHIFT[i++ & 3];
} else {
code = 0x10000 + (((code & 0x3ff) << 10) | (message.charCodeAt(++index) & 0x3ff));
blocks[i >> 2] |= (0xf0 | (code >> 18)) << SHIFT[i++ & 3];
blocks[i >> 2] |= (0x80 | ((code >> 12) & 0x3f)) << SHIFT[i++ & 3];
blocks[i >> 2] |= (0x80 | ((code >> 6) & 0x3f)) << SHIFT[i++ & 3];
blocks[i >> 2] |= (0x80 | (code & 0x3f)) << SHIFT[i++ & 3];
}
}
}
this.lastByteIndex = i;
this.bytes += i - this.start;
if (i >= 64) {
this.block = blocks[16];
this.start = i - 64;
this.hash();
this.hashed = true;
} else {
this.start = i;
}
}
return this;
};
Sha1.prototype.finalize = function () {
if (this.finalized) {
return;
}
this.finalized = true;
var blocks = this.blocks, i = this.lastByteIndex;
blocks[16] = this.block;
blocks[i >> 2] |= EXTRA[i & 3];
this.block = blocks[16];
if (i >= 56) {
if (!this.hashed) {
this.hash();
}
blocks[0] = this.block;
blocks[16] = blocks[1] = blocks[2] = blocks[3] =
blocks[4] = blocks[5] = blocks[6] = blocks[7] =
blocks[8] = blocks[9] = blocks[10] = blocks[11] =
blocks[12] = blocks[13] = blocks[14] = blocks[15] = 0;
}
blocks[15] = this.bytes << 3;
this.hash();
};
Sha1.prototype.hash = function () {
var a = this.h0, b = this.h1, c = this.h2, d = this.h3, e = this.h4;
var f, j, t, blocks = this.blocks;
for(j = 16; j < 80; ++j) {
t = blocks[j - 3] ^ blocks[j - 8] ^ blocks[j - 14] ^ blocks[j - 16];
blocks[j] = (t << 1) | (t >>> 31);
}
for(j = 0; j < 20; j += 5) {
f = (b & c) | ((~b) & d);
t = (a << 5) | (a >>> 27);
e = t + f + e + 1518500249 + blocks[j] << 0;
b = (b << 30) | (b >>> 2);
f = (a & b) | ((~a) & c);
t = (e << 5) | (e >>> 27);
d = t + f + d + 1518500249 + blocks[j + 1] << 0;
a = (a << 30) | (a >>> 2);
f = (e & a) | ((~e) & b);
t = (d << 5) | (d >>> 27);
c = t + f + c + 1518500249 + blocks[j + 2] << 0;
e = (e << 30) | (e >>> 2);
f = (d & e) | ((~d) & a);
t = (c << 5) | (c >>> 27);
b = t + f + b + 1518500249 + blocks[j + 3] << 0;
d = (d << 30) | (d >>> 2);
f = (c & d) | ((~c) & e);
t = (b << 5) | (b >>> 27);
a = t + f + a + 1518500249 + blocks[j + 4] << 0;
c = (c << 30) | (c >>> 2);
}
for(; j < 40; j += 5) {
f = b ^ c ^ d;
t = (a << 5) | (a >>> 27);
e = t + f + e + 1859775393 + blocks[j] << 0;
b = (b << 30) | (b >>> 2);
f = a ^ b ^ c;
t = (e << 5) | (e >>> 27);
d = t + f + d + 1859775393 + blocks[j + 1] << 0;
a = (a << 30) | (a >>> 2);
f = e ^ a ^ b;
t = (d << 5) | (d >>> 27);
c = t + f + c + 1859775393 + blocks[j + 2] << 0;
e = (e << 30) | (e >>> 2);
f = d ^ e ^ a;
t = (c << 5) | (c >>> 27);
b = t + f + b + 1859775393 + blocks[j + 3] << 0;
d = (d << 30) | (d >>> 2);
f = c ^ d ^ e;
t = (b << 5) | (b >>> 27);
a = t + f + a + 1859775393 + blocks[j + 4] << 0;
c = (c << 30) | (c >>> 2);
}
for(; j < 60; j += 5) {
f = (b & c) | (b & d) | (c & d);
t = (a << 5) | (a >>> 27);
e = t + f + e - 1894007588 + blocks[j] << 0;
b = (b << 30) | (b >>> 2);
f = (a & b) | (a & c) | (b & c);
t = (e << 5) | (e >>> 27);
d = t + f + d - 1894007588 + blocks[j + 1] << 0;
a = (a << 30) | (a >>> 2);
f = (e & a) | (e & b) | (a & b);
t = (d << 5) | (d >>> 27);
c = t + f + c - 1894007588 + blocks[j + 2] << 0;
e = (e << 30) | (e >>> 2);
f = (d & e) | (d & a) | (e & a);
t = (c << 5) | (c >>> 27);
b = t + f + b - 1894007588 + blocks[j + 3] << 0;
d = (d << 30) | (d >>> 2);
f = (c & d) | (c & e) | (d & e);
t = (b << 5) | (b >>> 27);
a = t + f + a - 1894007588 + blocks[j + 4] << 0;
c = (c << 30) | (c >>> 2);
}
for(; j < 80; j += 5) {
f = b ^ c ^ d;
t = (a << 5) | (a >>> 27);
e = t + f + e - 899497514 + blocks[j] << 0;
b = (b << 30) | (b >>> 2);
f = a ^ b ^ c;
t = (e << 5) | (e >>> 27);
d = t + f + d - 899497514 + blocks[j + 1] << 0;
a = (a << 30) | (a >>> 2);
f = e ^ a ^ b;
t = (d << 5) | (d >>> 27);
c = t + f + c - 899497514 + blocks[j + 2] << 0;
e = (e << 30) | (e >>> 2);
f = d ^ e ^ a;
t = (c << 5) | (c >>> 27);
b = t + f + b - 899497514 + blocks[j + 3] << 0;
d = (d << 30) | (d >>> 2);
f = c ^ d ^ e;
t = (b << 5) | (b >>> 27);
a = t + f + a - 899497514 + blocks[j + 4] << 0;
c = (c << 30) | (c >>> 2);
}
this.h0 = this.h0 + a << 0;
this.h1 = this.h1 + b << 0;
this.h2 = this.h2 + c << 0;
this.h3 = this.h3 + d << 0;
this.h4 = this.h4 + e << 0;
};
Sha1.prototype.hex = function () {
this.finalize();
var h0 = this.h0, h1 = this.h1, h2 = this.h2, h3 = this.h3, h4 = this.h4;
return HEX_CHARS[(h0 >> 28) & 0x0F] + HEX_CHARS[(h0 >> 24) & 0x0F] +
HEX_CHARS[(h0 >> 20) & 0x0F] + HEX_CHARS[(h0 >> 16) & 0x0F] +
HEX_CHARS[(h0 >> 12) & 0x0F] + HEX_CHARS[(h0 >> 8) & 0x0F] +
HEX_CHARS[(h0 >> 4) & 0x0F] + HEX_CHARS[h0 & 0x0F] +
HEX_CHARS[(h1 >> 28) & 0x0F] + HEX_CHARS[(h1 >> 24) & 0x0F] +
HEX_CHARS[(h1 >> 20) & 0x0F] + HEX_CHARS[(h1 >> 16) & 0x0F] +
HEX_CHARS[(h1 >> 12) & 0x0F] + HEX_CHARS[(h1 >> 8) & 0x0F] +
HEX_CHARS[(h1 >> 4) & 0x0F] + HEX_CHARS[h1 & 0x0F] +
HEX_CHARS[(h2 >> 28) & 0x0F] + HEX_CHARS[(h2 >> 24) & 0x0F] +
HEX_CHARS[(h2 >> 20) & 0x0F] + HEX_CHARS[(h2 >> 16) & 0x0F] +
HEX_CHARS[(h2 >> 12) & 0x0F] + HEX_CHARS[(h2 >> 8) & 0x0F] +
HEX_CHARS[(h2 >> 4) & 0x0F] + HEX_CHARS[h2 & 0x0F] +
HEX_CHARS[(h3 >> 28) & 0x0F] + HEX_CHARS[(h3 >> 24) & 0x0F] +
HEX_CHARS[(h3 >> 20) & 0x0F] + HEX_CHARS[(h3 >> 16) & 0x0F] +
HEX_CHARS[(h3 >> 12) & 0x0F] + HEX_CHARS[(h3 >> 8) & 0x0F] +
HEX_CHARS[(h3 >> 4) & 0x0F] + HEX_CHARS[h3 & 0x0F] +
HEX_CHARS[(h4 >> 28) & 0x0F] + HEX_CHARS[(h4 >> 24) & 0x0F] +
HEX_CHARS[(h4 >> 20) & 0x0F] + HEX_CHARS[(h4 >> 16) & 0x0F] +
HEX_CHARS[(h4 >> 12) & 0x0F] + HEX_CHARS[(h4 >> 8) & 0x0F] +
HEX_CHARS[(h4 >> 4) & 0x0F] + HEX_CHARS[h4 & 0x0F];
};
Sha1.prototype.toString = Sha1.prototype.hex;
Sha1.prototype.digest = function () {
this.finalize();
var h0 = this.h0, h1 = this.h1, h2 = this.h2, h3 = this.h3, h4 = this.h4;
return [
(h0 >> 24) & 0xFF, (h0 >> 16) & 0xFF, (h0 >> 8) & 0xFF, h0 & 0xFF,
(h1 >> 24) & 0xFF, (h1 >> 16) & 0xFF, (h1 >> 8) & 0xFF, h1 & 0xFF,
(h2 >> 24) & 0xFF, (h2 >> 16) & 0xFF, (h2 >> 8) & 0xFF, h2 & 0xFF,
(h3 >> 24) & 0xFF, (h3 >> 16) & 0xFF, (h3 >> 8) & 0xFF, h3 & 0xFF,
(h4 >> 24) & 0xFF, (h4 >> 16) & 0xFF, (h4 >> 8) & 0xFF, h4 & 0xFF
];
};
Sha1.prototype.array = Sha1.prototype.digest;
Sha1.prototype.arrayBuffer = function () {
this.finalize();
var buffer = new ArrayBuffer(20);
var dataView = new DataView(buffer);
dataView.setUint32(0, this.h0);
dataView.setUint32(4, this.h1);
dataView.setUint32(8, this.h2);
dataView.setUint32(12, this.h3);
dataView.setUint32(16, this.h4);
return buffer;
};
var exports = createMethod();
if (COMMON_JS) {
module.exports = exports;
} else {
root.sha1 = exports;
if (AMD) {
define(function () {
return exports;
});
}
}
})();
+function() {
var HASHLENGTH = 5;
document.getElementById('clickme').onclick = function() {
// get all the values as objects
var values = JSON.parse(document.getElementById('sample').value);
for (var c = 0; c < values.length; c++) {
// Hash it and substring it given the hashlength
values[c].hash = sha1(JSON.stringify(values[c])).substring(0,HASHLENGTH);
// If you don't need the collision detection, you can just remove these loops.
// check for collisions
for(var i = 0;i < c; i++) {
// collision detected. add a dependable value to get a new hash.
if(values[i].hash == values[c].hash) {
if(values[c].hasOwnProperty('_change')) {
values[c]._change = sha1(values[c]._change);
}
else {
values[c]._change = sha1(values[c].hash);
}
c--;break; // return to same thing for a rehash
}
}
}
console.log(JSON.stringify(values,null,4));
}
}();
textarea { width:100%;height:200px;}
<button id="clickme"> Parse </button>
<textarea id="sample">
[
{
"name": "Jack Potts",
"age": "56"
}, {
"name": "Rusty Carr",
"age": "31"
},
{
"name": "Rusty Carr",
"age": "31"
},
{
"name": "Rusty Carr",
"age": "31"
},
{
"name": "Rusty Carr",
"age": "31"
},
{
"name": "Rusty Carr",
"age": "31"
},
{
"name": "Rusty Carr",
"age": "31"
}
]
</textarea>
I won't be updating the JSON file with whatever I generate.
I need a way to take the object in question, create a URL for it, then when the URL is visited use the URL to get back to that object in the array.
然后使用对象在数组中的索引：这样people/0将return{"name": "Jack Potts", "age": "56"}，people/1将return{"name": "Rusty Carr", "age": "31"},等等...
如果您只想要比 MD5 更短的输出，但对截断为您需要的长度的唯一性感到满意，那么每一位都与任何其他位一样随机，即您选择的位的任何子集都只是与任何其他子集一样好。
但请注意，如果两个名称相同，您将获得相同的哈希值。
因为您必须意识到哈希值越短，冲突的变化就越大，您正在对哈希长度与唯一性进行权衡，这还不错，只要确保您有足够的唯一性来满足您的需求。
这是获取 MD5 散列的本机 JavaScript 代码，缩短为所需长度。请注意，哈希值越短，发生冲突的可能性就越大。
var md5 = function(d){var r = M(V(Y(X(d),8*d.length)));return r.toLowerCase()};function M(d){for(var _,m="0123456789ABCDEF",f="",r=0;r<d.length;r++)_=d.charCodeAt(r),f+=m.charAt(_>>>4&15)+m.charAt(15&_);return f}function X(d){for(var _=Array(d.length>>2),m=0;m<_.length;m++)_[m]=0;for(m=0;m<8*d.length;m+=8)_[m>>5]|=(255&d.charCodeAt(m/8))<<m%32;return _}function V(d){for(var _="",m=0;m<32*d.length;m+=8)_+=String.fromCharCode(d[m>>5]>>>m%32&255);return _}function Y(d,_){d[_>>5]|=128<<_%32,d[14+(_+64>>>9<<4)]=_;for(var m=1732584193,f=-271733879,r=-1732584194,i=271733878,n=0;n<d.length;n+=16){var h=m,t=f,g=r,e=i;f=md5_ii(f=md5_ii(f=md5_ii(f=md5_ii(f=md5_hh(f=md5_hh(f=md5_hh(f=md5_hh(f=md5_gg(f=md5_gg(f=md5_gg(f=md5_gg(f=md5_ff(f=md5_ff(f=md5_ff(f=md5_ff(f,r=md5_ff(r,i=md5_ff(i,m=md5_ff(m,f,r,i,d[n+0],7,-680876936),f,r,d[n+1],12,-389564586),m,f,d[n+2],17,606105819),i,m,d[n+3],22,-1044525330),r=md5_ff(r,i=md5_ff(i,m=md5_ff(m,f,r,i,d[n+4],7,-176418897),f,r,d[n+5],12,1200080426),m,f,d[n+6],17,-1473231341),i,m,d[n+7],22,-45705983),r=md5_ff(r,i=md5_ff(i,m=md5_ff(m,f,r,i,d[n+8],7,1770035416),f,r,d[n+9],12,-1958414417),m,f,d[n+10],17,-42063),i,m,d[n+11],22,-1990404162),r=md5_ff(r,i=md5_ff(i,m=md5_ff(m,f,r,i,d[n+12],7,1804603682),f,r,d[n+13],12,-40341101),m,f,d[n+14],17,-1502002290),i,m,d[n+15],22,1236535329),r=md5_gg(r,i=md5_gg(i,m=md5_gg(m,f,r,i,d[n+1],5,-165796510),f,r,d[n+6],9,-1069501632),m,f,d[n+11],14,643717713),i,m,d[n+0],20,-373897302),r=md5_gg(r,i=md5_gg(i,m=md5_gg(m,f,r,i,d[n+5],5,-701558691),f,r,d[n+10],9,38016083),m,f,d[n+15],14,-660478335),i,m,d[n+4],20,-405537848),r=md5_gg(r,i=md5_gg(i,m=md5_gg(m,f,r,i,d[n+9],5,568446438),f,r,d[n+14],9,-1019803690),m,f,d[n+3],14,-187363961),i,m,d[n+8],20,1163531501),r=md5_gg(r,i=md5_gg(i,m=md5_gg(m,f,r,i,d[n+13],5,-1444681467),f,r,d[n+2],9,-51403784),m,f,d[n+7],14,1735328473),i,m,d[n+12],20,-1926607734),r=md5_hh(r,i=md5_hh(i,m=md5_hh(m,f,r,i,d[n+5],4,-378558),f,r,d[n+8],11,-2022574463),m,f,d[n+11],16,1839030562),i,m,d[n+14],23,-35309556),r=md5_hh(r,i=md5_hh(i,m=md5_hh(m,f,r,i,d[n+1],4,-1530992060),f,r,d[n+4],11,1272893353),m,f,d[n+7],16,-155497632),i,m,d[n+10],23,-1094730640),r=md5_hh(r,i=md5_hh(i,m=md5_hh(m,f,r,i,d[n+13],4,681279174),f,r,d[n+0],11,-358537222),m,f,d[n+3],16,-722521979),i,m,d[n+6],23,76029189),r=md5_hh(r,i=md5_hh(i,m=md5_hh(m,f,r,i,d[n+9],4,-640364487),f,r,d[n+12],11,-421815835),m,f,d[n+15],16,530742520),i,m,d[n+2],23,-995338651),r=md5_ii(r,i=md5_ii(i,m=md5_ii(m,f,r,i,d[n+0],6,-198630844),f,r,d[n+7],10,1126891415),m,f,d[n+14],15,-1416354905),i,m,d[n+5],21,-57434055),r=md5_ii(r,i=md5_ii(i,m=md5_ii(m,f,r,i,d[n+12],6,1700485571),f,r,d[n+3],10,-1894986606),m,f,d[n+10],15,-1051523),i,m,d[n+1],21,-2054922799),r=md5_ii(r,i=md5_ii(i,m=md5_ii(m,f,r,i,d[n+8],6,1873313359),f,r,d[n+15],10,-30611744),m,f,d[n+6],15,-1560198380),i,m,d[n+13],21,1309151649),r=md5_ii(r,i=md5_ii(i,m=md5_ii(m,f,r,i,d[n+4],6,-145523070),f,r,d[n+11],10,-1120210379),m,f,d[n+2],15,718787259),i,m,d[n+9],21,-343485551),m=safe_add(m,h),f=safe_add(f,t),r=safe_add(r,g),i=safe_add(i,e)}return Array(m,f,r,i)}function md5_cmn(d,_,m,f,r,i){return safe_add(bit_rol(safe_add(safe_add(_,d),safe_add(f,i)),r),m)}function md5_ff(d,_,m,f,r,i,n){return md5_cmn(_&m|~_&f,d,_,r,i,n)}function md5_gg(d,_,m,f,r,i,n){return md5_cmn(_&f|m&~f,d,_,r,i,n)}function md5_hh(d,_,m,f,r,i,n){return md5_cmn(_^m^f,d,_,r,i,n)}function md5_ii(d,_,m,f,r,i,n){return md5_cmn(m^(_|~f),d,_,r,i,n)}function safe_add(d,_){var m=(65535&d)+(65535&_);return(d>>16)+(_>>16)+(m>>16)<<16|65535&m}function bit_rol(d,_){return d<<_|d>>>32-_}
function tinymd5(str, length) {
length = length || 16;
str = window.btoa(md5(str)).replace(/[aiueoAIUEO\+\/]/g, '').substring(0, length);
if(str.length < length) {
str += Array(length - str.length).join('=');
}
return str;
}
// example usage:
var shortHash = tinymd5(JSON.stringify(someObj), 16);
md5函数来自
tinymd5函数是根据https://rolandeckert.com/notes/md5
代码转换为JavaScript
我在 JSON 文件中有 array 个 object。 object 没有唯一的 id，所以我需要创建一个唯一的 id 或唯一的 string.
[
{
"name": "Jack Potts",
"age": "56"
}, {
"name": "Rusty Carr",
"age": "31"
}
]
我知道我可以使用 MD5，传入 object，但我要在 URL 中使用 string，所以我会希望它更短。
而不是 /people/3449c9e5e332f1dbb81505cd739fbf3f，我更喜欢 /people/1dbb81505。
它仍然需要代表 object，因为我要从 URL 中再次查找此人。
是否有任何生成 string 比 MD5 string.. 短的东西？
我猜测 MD5 是我的 best/only 选项，但我想我会问。
更新
我可能不够清楚。我不只是需要生成一个唯一的 id。我不会用我生成的任何内容更新 JSON 文件。
我需要一种方法来获取有问题的 object，为它创建一个 URL，然后在访问 URL 时使用 URL 返回array.
object
据我所知，如果你一遍又一遍地将相同的 string 传递给 MD5，它总是 return 相同的 MD5 string 因为它是表示。出于同样的原因，人们在数据库中存储密码时不使用它吗？
也许 MD5 没问题，我只是想可能有一些东西可以产生更短的 string，这是数据的 表示 。这是我的问题。
更新 2
array 中的人可能会改变。可能会添加和删除人员，因此使用 array 索引将不起作用。
使用以下函数：
function generateUID() {
var firstPart = (Math.random() * 46656) | 0;
var secondPart = (Math.random() * 46656) | 0;
firstPart = ("000" + firstPart.toString(36)).slice(-3);
secondPart = ("000" + secondPart.toString(36)).slice(-3);
return firstPart + secondPart;
}
一个 6 个字符的字母数字序列足以随机索引 10k 的集合（366 = 22 亿，363 = 46656）。
我建议你使用sha1，它处理的散列相对较短。假设您的数据集相对有限 < 1000000000000...等等...项目发生冲突的可能性应该很小。
https://github.com/emn178/js-sha1 是一个不错的图书馆
编辑修改它以使其更短
它现在做了一个子字符串，+ 一个应该可靠的碰撞检测修改，只要项目的顺序在具有 smae 值的情况下不会改变。但话又说回来，如果它们具有相同的值，那应该无关紧要;-)
/*
* [js-sha1]{@link https://github.com/emn178/js-sha1}
*
* @version 0.4.1
* @author Chen, Yi-Cyuan [emn178@gmail.com]
* @copyright Chen, Yi-Cyuan 2014-2016
* @license MIT
*/
/*jslint bitwise: true */
(function() {
'use strict';
var root = typeof window === 'object' ? window : {};
var NODE_JS = !root.JS_SHA1_NO_NODE_JS && typeof process === 'object' && process.versions && process.versions.node;
if (NODE_JS) {
root = global;
}
var COMMON_JS = !root.JS_SHA1_NO_COMMON_JS && typeof module === 'object' && module.exports;
var AMD = typeof define === 'function' && define.amd;
var HEX_CHARS = '0123456789abcdef'.split('');
var EXTRA = [-2147483648, 8388608, 32768, 128];
var SHIFT = [24, 16, 8, 0];
var OUTPUT_TYPES = ['hex', 'array', 'digest', 'arrayBuffer'];
var blocks = [];
var createOutputMethod = function (outputType) {
return function (message) {
return new Sha1(true).update(message)[outputType]();
};
};
var createMethod = function () {
var method = createOutputMethod('hex');
if (NODE_JS) {
method = nodeWrap(method);
}
method.create = function () {
return new Sha1();
};
method.update = function (message) {
return method.create().update(message);
};
for (var i = 0; i < OUTPUT_TYPES.length; ++i) {
var type = OUTPUT_TYPES[i];
method[type] = createOutputMethod(type);
}
return method;
};
var nodeWrap = function (method) {
var crypto = require('crypto');
var Buffer = require('buffer').Buffer;
var nodeMethod = function (message) {
if (typeof message === 'string') {
return crypto.createHash('sha1').update(message, 'utf8').digest('hex');
} else if (message.constructor === ArrayBuffer) {
message = new Uint8Array(message);
} else if (message.length === undefined) {
return method(message);
}
return crypto.createHash('sha1').update(new Buffer(message)).digest('hex');
};
return nodeMethod;
};
function Sha1(sharedMemory) {
if (sharedMemory) {
blocks[0] = blocks[16] = blocks[1] = blocks[2] = blocks[3] =
blocks[4] = blocks[5] = blocks[6] = blocks[7] =
blocks[8] = blocks[9] = blocks[10] = blocks[11] =
blocks[12] = blocks[13] = blocks[14] = blocks[15] = 0;
this.blocks = blocks;
} else {
this.blocks = [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0];
}
this.h0 = 0x67452301;
this.h1 = 0xEFCDAB89;
this.h2 = 0x98BADCFE;
this.h3 = 0x10325476;
this.h4 = 0xC3D2E1F0;
this.block = this.start = this.bytes = 0;
this.finalized = this.hashed = false;
this.first = true;
}
Sha1.prototype.update = function (message) {
if (this.finalized) {
return;
}
var notString = typeof(message) !== 'string';
if (notString && message.constructor === root.ArrayBuffer) {
message = new Uint8Array(message);
}
var code, index = 0, i, length = message.length || 0, blocks = this.blocks;
while (index < length) {
if (this.hashed) {
this.hashed = false;
blocks[0] = this.block;
blocks[16] = blocks[1] = blocks[2] = blocks[3] =
blocks[4] = blocks[5] = blocks[6] = blocks[7] =
blocks[8] = blocks[9] = blocks[10] = blocks[11] =
blocks[12] = blocks[13] = blocks[14] = blocks[15] = 0;
}
if(notString) {
for (i = this.start; index < length && i < 64; ++index) {
blocks[i >> 2] |= message[index] << SHIFT[i++ & 3];
}
} else {
for (i = this.start; index < length && i < 64; ++index) {
code = message.charCodeAt(index);
if (code < 0x80) {
blocks[i >> 2] |= code << SHIFT[i++ & 3];
} else if (code < 0x800) {
blocks[i >> 2] |= (0xc0 | (code >> 6)) << SHIFT[i++ & 3];
blocks[i >> 2] |= (0x80 | (code & 0x3f)) << SHIFT[i++ & 3];
} else if (code < 0xd800 || code >= 0xe000) {
blocks[i >> 2] |= (0xe0 | (code >> 12)) << SHIFT[i++ & 3];
blocks[i >> 2] |= (0x80 | ((code >> 6) & 0x3f)) << SHIFT[i++ & 3];
blocks[i >> 2] |= (0x80 | (code & 0x3f)) << SHIFT[i++ & 3];
} else {
code = 0x10000 + (((code & 0x3ff) << 10) | (message.charCodeAt(++index) & 0x3ff));
blocks[i >> 2] |= (0xf0 | (code >> 18)) << SHIFT[i++ & 3];
blocks[i >> 2] |= (0x80 | ((code >> 12) & 0x3f)) << SHIFT[i++ & 3];
blocks[i >> 2] |= (0x80 | ((code >> 6) & 0x3f)) << SHIFT[i++ & 3];
blocks[i >> 2] |= (0x80 | (code & 0x3f)) << SHIFT[i++ & 3];
}
}
}
this.lastByteIndex = i;
this.bytes += i - this.start;
if (i >= 64) {
this.block = blocks[16];
this.start = i - 64;
this.hash();
this.hashed = true;
} else {
this.start = i;
}
}
return this;
};
Sha1.prototype.finalize = function () {
if (this.finalized) {
return;
}
this.finalized = true;
var blocks = this.blocks, i = this.lastByteIndex;
blocks[16] = this.block;
blocks[i >> 2] |= EXTRA[i & 3];
this.block = blocks[16];
if (i >= 56) {
if (!this.hashed) {
this.hash();
}
blocks[0] = this.block;
blocks[16] = blocks[1] = blocks[2] = blocks[3] =
blocks[4] = blocks[5] = blocks[6] = blocks[7] =
blocks[8] = blocks[9] = blocks[10] = blocks[11] =
blocks[12] = blocks[13] = blocks[14] = blocks[15] = 0;
}
blocks[15] = this.bytes << 3;
this.hash();
};
Sha1.prototype.hash = function () {
var a = this.h0, b = this.h1, c = this.h2, d = this.h3, e = this.h4;
var f, j, t, blocks = this.blocks;
for(j = 16; j < 80; ++j) {
t = blocks[j - 3] ^ blocks[j - 8] ^ blocks[j - 14] ^ blocks[j - 16];
blocks[j] = (t << 1) | (t >>> 31);
}
for(j = 0; j < 20; j += 5) {
f = (b & c) | ((~b) & d);
t = (a << 5) | (a >>> 27);
e = t + f + e + 1518500249 + blocks[j] << 0;
b = (b << 30) | (b >>> 2);
f = (a & b) | ((~a) & c);
t = (e << 5) | (e >>> 27);
d = t + f + d + 1518500249 + blocks[j + 1] << 0;
a = (a << 30) | (a >>> 2);
f = (e & a) | ((~e) & b);
t = (d << 5) | (d >>> 27);
c = t + f + c + 1518500249 + blocks[j + 2] << 0;
e = (e << 30) | (e >>> 2);
f = (d & e) | ((~d) & a);
t = (c << 5) | (c >>> 27);
b = t + f + b + 1518500249 + blocks[j + 3] << 0;
d = (d << 30) | (d >>> 2);
f = (c & d) | ((~c) & e);
t = (b << 5) | (b >>> 27);
a = t + f + a + 1518500249 + blocks[j + 4] << 0;
c = (c << 30) | (c >>> 2);
}
for(; j < 40; j += 5) {
f = b ^ c ^ d;
t = (a << 5) | (a >>> 27);
e = t + f + e + 1859775393 + blocks[j] << 0;
b = (b << 30) | (b >>> 2);
f = a ^ b ^ c;
t = (e << 5) | (e >>> 27);
d = t + f + d + 1859775393 + blocks[j + 1] << 0;
a = (a << 30) | (a >>> 2);
f = e ^ a ^ b;
t = (d << 5) | (d >>> 27);
c = t + f + c + 1859775393 + blocks[j + 2] << 0;
e = (e << 30) | (e >>> 2);
f = d ^ e ^ a;
t = (c << 5) | (c >>> 27);
b = t + f + b + 1859775393 + blocks[j + 3] << 0;
d = (d << 30) | (d >>> 2);
f = c ^ d ^ e;
t = (b << 5) | (b >>> 27);
a = t + f + a + 1859775393 + blocks[j + 4] << 0;
c = (c << 30) | (c >>> 2);
}
for(; j < 60; j += 5) {
f = (b & c) | (b & d) | (c & d);
t = (a << 5) | (a >>> 27);
e = t + f + e - 1894007588 + blocks[j] << 0;
b = (b << 30) | (b >>> 2);
f = (a & b) | (a & c) | (b & c);
t = (e << 5) | (e >>> 27);
d = t + f + d - 1894007588 + blocks[j + 1] << 0;
a = (a << 30) | (a >>> 2);
f = (e & a) | (e & b) | (a & b);
t = (d << 5) | (d >>> 27);
c = t + f + c - 1894007588 + blocks[j + 2] << 0;
e = (e << 30) | (e >>> 2);
f = (d & e) | (d & a) | (e & a);
t = (c << 5) | (c >>> 27);
b = t + f + b - 1894007588 + blocks[j + 3] << 0;
d = (d << 30) | (d >>> 2);
f = (c & d) | (c & e) | (d & e);
t = (b << 5) | (b >>> 27);
a = t + f + a - 1894007588 + blocks[j + 4] << 0;
c = (c << 30) | (c >>> 2);
}
for(; j < 80; j += 5) {
f = b ^ c ^ d;
t = (a << 5) | (a >>> 27);
e = t + f + e - 899497514 + blocks[j] << 0;
b = (b << 30) | (b >>> 2);
f = a ^ b ^ c;
t = (e << 5) | (e >>> 27);
d = t + f + d - 899497514 + blocks[j + 1] << 0;
a = (a << 30) | (a >>> 2);
f = e ^ a ^ b;
t = (d << 5) | (d >>> 27);
c = t + f + c - 899497514 + blocks[j + 2] << 0;
e = (e << 30) | (e >>> 2);
f = d ^ e ^ a;
t = (c << 5) | (c >>> 27);
b = t + f + b - 899497514 + blocks[j + 3] << 0;
d = (d << 30) | (d >>> 2);
f = c ^ d ^ e;
t = (b << 5) | (b >>> 27);
a = t + f + a - 899497514 + blocks[j + 4] << 0;
c = (c << 30) | (c >>> 2);
}
this.h0 = this.h0 + a << 0;
this.h1 = this.h1 + b << 0;
this.h2 = this.h2 + c << 0;
this.h3 = this.h3 + d << 0;
this.h4 = this.h4 + e << 0;
};
Sha1.prototype.hex = function () {
this.finalize();
var h0 = this.h0, h1 = this.h1, h2 = this.h2, h3 = this.h3, h4 = this.h4;
return HEX_CHARS[(h0 >> 28) & 0x0F] + HEX_CHARS[(h0 >> 24) & 0x0F] +
HEX_CHARS[(h0 >> 20) & 0x0F] + HEX_CHARS[(h0 >> 16) & 0x0F] +
HEX_CHARS[(h0 >> 12) & 0x0F] + HEX_CHARS[(h0 >> 8) & 0x0F] +
HEX_CHARS[(h0 >> 4) & 0x0F] + HEX_CHARS[h0 & 0x0F] +
HEX_CHARS[(h1 >> 28) & 0x0F] + HEX_CHARS[(h1 >> 24) & 0x0F] +
HEX_CHARS[(h1 >> 20) & 0x0F] + HEX_CHARS[(h1 >> 16) & 0x0F] +
HEX_CHARS[(h1 >> 12) & 0x0F] + HEX_CHARS[(h1 >> 8) & 0x0F] +
HEX_CHARS[(h1 >> 4) & 0x0F] + HEX_CHARS[h1 & 0x0F] +
HEX_CHARS[(h2 >> 28) & 0x0F] + HEX_CHARS[(h2 >> 24) & 0x0F] +
HEX_CHARS[(h2 >> 20) & 0x0F] + HEX_CHARS[(h2 >> 16) & 0x0F] +
HEX_CHARS[(h2 >> 12) & 0x0F] + HEX_CHARS[(h2 >> 8) & 0x0F] +
HEX_CHARS[(h2 >> 4) & 0x0F] + HEX_CHARS[h2 & 0x0F] +
HEX_CHARS[(h3 >> 28) & 0x0F] + HEX_CHARS[(h3 >> 24) & 0x0F] +
HEX_CHARS[(h3 >> 20) & 0x0F] + HEX_CHARS[(h3 >> 16) & 0x0F] +
HEX_CHARS[(h3 >> 12) & 0x0F] + HEX_CHARS[(h3 >> 8) & 0x0F] +
HEX_CHARS[(h3 >> 4) & 0x0F] + HEX_CHARS[h3 & 0x0F] +
HEX_CHARS[(h4 >> 28) & 0x0F] + HEX_CHARS[(h4 >> 24) & 0x0F] +
HEX_CHARS[(h4 >> 20) & 0x0F] + HEX_CHARS[(h4 >> 16) & 0x0F] +
HEX_CHARS[(h4 >> 12) & 0x0F] + HEX_CHARS[(h4 >> 8) & 0x0F] +
HEX_CHARS[(h4 >> 4) & 0x0F] + HEX_CHARS[h4 & 0x0F];
};
Sha1.prototype.toString = Sha1.prototype.hex;
Sha1.prototype.digest = function () {
this.finalize();
var h0 = this.h0, h1 = this.h1, h2 = this.h2, h3 = this.h3, h4 = this.h4;
return [
(h0 >> 24) & 0xFF, (h0 >> 16) & 0xFF, (h0 >> 8) & 0xFF, h0 & 0xFF,
(h1 >> 24) & 0xFF, (h1 >> 16) & 0xFF, (h1 >> 8) & 0xFF, h1 & 0xFF,
(h2 >> 24) & 0xFF, (h2 >> 16) & 0xFF, (h2 >> 8) & 0xFF, h2 & 0xFF,
(h3 >> 24) & 0xFF, (h3 >> 16) & 0xFF, (h3 >> 8) & 0xFF, h3 & 0xFF,
(h4 >> 24) & 0xFF, (h4 >> 16) & 0xFF, (h4 >> 8) & 0xFF, h4 & 0xFF
];
};
Sha1.prototype.array = Sha1.prototype.digest;
Sha1.prototype.arrayBuffer = function () {
this.finalize();
var buffer = new ArrayBuffer(20);
var dataView = new DataView(buffer);
dataView.setUint32(0, this.h0);
dataView.setUint32(4, this.h1);
dataView.setUint32(8, this.h2);
dataView.setUint32(12, this.h3);
dataView.setUint32(16, this.h4);
return buffer;
};
var exports = createMethod();
if (COMMON_JS) {
module.exports = exports;
} else {
root.sha1 = exports;
if (AMD) {
define(function () {
return exports;
});
}
}
})();
+function() {
var HASHLENGTH = 5;
document.getElementById('clickme').onclick = function() {
// get all the values as objects
var values = JSON.parse(document.getElementById('sample').value);
for (var c = 0; c < values.length; c++) {
// Hash it and substring it given the hashlength
values[c].hash = sha1(JSON.stringify(values[c])).substring(0,HASHLENGTH);
// If you don't need the collision detection, you can just remove these loops.
// check for collisions
for(var i = 0;i < c; i++) {
// collision detected. add a dependable value to get a new hash.
if(values[i].hash == values[c].hash) {
if(values[c].hasOwnProperty('_change')) {
values[c]._change = sha1(values[c]._change);
}
else {
values[c]._change = sha1(values[c].hash);
}
c--;break; // return to same thing for a rehash
}
}
}
console.log(JSON.stringify(values,null,4));
}
}();
textarea { width:100%;height:200px;}
<button id="clickme"> Parse </button>
<textarea id="sample">
[
{
"name": "Jack Potts",
"age": "56"
}, {
"name": "Rusty Carr",
"age": "31"
},
{
"name": "Rusty Carr",
"age": "31"
},
{
"name": "Rusty Carr",
"age": "31"
},
{
"name": "Rusty Carr",
"age": "31"
},
{
"name": "Rusty Carr",
"age": "31"
},
{
"name": "Rusty Carr",
"age": "31"
}
]
</textarea>
I won't be updating the JSON file with whatever I generate.
I need a way to take the object in question, create a URL for it, then when the URL is visited use the URL to get back to that object in the array.
然后使用对象在数组中的索引：这样people/0将return{"name": "Jack Potts", "age": "56"}，people/1将return{"name": "Rusty Carr", "age": "31"},等等...
如果您只想要比 MD5 更短的输出，但对截断为您需要的长度的唯一性感到满意，那么每一位都与任何其他位一样随机，即您选择的位的任何子集都只是与任何其他子集一样好。
但请注意，如果两个名称相同，您将获得相同的哈希值。
因为您必须意识到哈希值越短，冲突的变化就越大，您正在对哈希长度与唯一性进行权衡，这还不错，只要确保您有足够的唯一性来满足您的需求。
这是获取 MD5 散列的本机 JavaScript 代码，缩短为所需长度。请注意，哈希值越短，发生冲突的可能性就越大。
var md5 = function(d){var r = M(V(Y(X(d),8*d.length)));return r.toLowerCase()};function M(d){for(var _,m="0123456789ABCDEF",f="",r=0;r<d.length;r++)_=d.charCodeAt(r),f+=m.charAt(_>>>4&15)+m.charAt(15&_);return f}function X(d){for(var _=Array(d.length>>2),m=0;m<_.length;m++)_[m]=0;for(m=0;m<8*d.length;m+=8)_[m>>5]|=(255&d.charCodeAt(m/8))<<m%32;return _}function V(d){for(var _="",m=0;m<32*d.length;m+=8)_+=String.fromCharCode(d[m>>5]>>>m%32&255);return _}function Y(d,_){d[_>>5]|=128<<_%32,d[14+(_+64>>>9<<4)]=_;for(var m=1732584193,f=-271733879,r=-1732584194,i=271733878,n=0;n<d.length;n+=16){var h=m,t=f,g=r,e=i;f=md5_ii(f=md5_ii(f=md5_ii(f=md5_ii(f=md5_hh(f=md5_hh(f=md5_hh(f=md5_hh(f=md5_gg(f=md5_gg(f=md5_gg(f=md5_gg(f=md5_ff(f=md5_ff(f=md5_ff(f=md5_ff(f,r=md5_ff(r,i=md5_ff(i,m=md5_ff(m,f,r,i,d[n+0],7,-680876936),f,r,d[n+1],12,-389564586),m,f,d[n+2],17,606105819),i,m,d[n+3],22,-1044525330),r=md5_ff(r,i=md5_ff(i,m=md5_ff(m,f,r,i,d[n+4],7,-176418897),f,r,d[n+5],12,1200080426),m,f,d[n+6],17,-1473231341),i,m,d[n+7],22,-45705983),r=md5_ff(r,i=md5_ff(i,m=md5_ff(m,f,r,i,d[n+8],7,1770035416),f,r,d[n+9],12,-1958414417),m,f,d[n+10],17,-42063),i,m,d[n+11],22,-1990404162),r=md5_ff(r,i=md5_ff(i,m=md5_ff(m,f,r,i,d[n+12],7,1804603682),f,r,d[n+13],12,-40341101),m,f,d[n+14],17,-1502002290),i,m,d[n+15],22,1236535329),r=md5_gg(r,i=md5_gg(i,m=md5_gg(m,f,r,i,d[n+1],5,-165796510),f,r,d[n+6],9,-1069501632),m,f,d[n+11],14,643717713),i,m,d[n+0],20,-373897302),r=md5_gg(r,i=md5_gg(i,m=md5_gg(m,f,r,i,d[n+5],5,-701558691),f,r,d[n+10],9,38016083),m,f,d[n+15],14,-660478335),i,m,d[n+4],20,-405537848),r=md5_gg(r,i=md5_gg(i,m=md5_gg(m,f,r,i,d[n+9],5,568446438),f,r,d[n+14],9,-1019803690),m,f,d[n+3],14,-187363961),i,m,d[n+8],20,1163531501),r=md5_gg(r,i=md5_gg(i,m=md5_gg(m,f,r,i,d[n+13],5,-1444681467),f,r,d[n+2],9,-51403784),m,f,d[n+7],14,1735328473),i,m,d[n+12],20,-1926607734),r=md5_hh(r,i=md5_hh(i,m=md5_hh(m,f,r,i,d[n+5],4,-378558),f,r,d[n+8],11,-2022574463),m,f,d[n+11],16,1839030562),i,m,d[n+14],23,-35309556),r=md5_hh(r,i=md5_hh(i,m=md5_hh(m,f,r,i,d[n+1],4,-1530992060),f,r,d[n+4],11,1272893353),m,f,d[n+7],16,-155497632),i,m,d[n+10],23,-1094730640),r=md5_hh(r,i=md5_hh(i,m=md5_hh(m,f,r,i,d[n+13],4,681279174),f,r,d[n+0],11,-358537222),m,f,d[n+3],16,-722521979),i,m,d[n+6],23,76029189),r=md5_hh(r,i=md5_hh(i,m=md5_hh(m,f,r,i,d[n+9],4,-640364487),f,r,d[n+12],11,-421815835),m,f,d[n+15],16,530742520),i,m,d[n+2],23,-995338651),r=md5_ii(r,i=md5_ii(i,m=md5_ii(m,f,r,i,d[n+0],6,-198630844),f,r,d[n+7],10,1126891415),m,f,d[n+14],15,-1416354905),i,m,d[n+5],21,-57434055),r=md5_ii(r,i=md5_ii(i,m=md5_ii(m,f,r,i,d[n+12],6,1700485571),f,r,d[n+3],10,-1894986606),m,f,d[n+10],15,-1051523),i,m,d[n+1],21,-2054922799),r=md5_ii(r,i=md5_ii(i,m=md5_ii(m,f,r,i,d[n+8],6,1873313359),f,r,d[n+15],10,-30611744),m,f,d[n+6],15,-1560198380),i,m,d[n+13],21,1309151649),r=md5_ii(r,i=md5_ii(i,m=md5_ii(m,f,r,i,d[n+4],6,-145523070),f,r,d[n+11],10,-1120210379),m,f,d[n+2],15,718787259),i,m,d[n+9],21,-343485551),m=safe_add(m,h),f=safe_add(f,t),r=safe_add(r,g),i=safe_add(i,e)}return Array(m,f,r,i)}function md5_cmn(d,_,m,f,r,i){return safe_add(bit_rol(safe_add(safe_add(_,d),safe_add(f,i)),r),m)}function md5_ff(d,_,m,f,r,i,n){return md5_cmn(_&m|~_&f,d,_,r,i,n)}function md5_gg(d,_,m,f,r,i,n){return md5_cmn(_&f|m&~f,d,_,r,i,n)}function md5_hh(d,_,m,f,r,i,n){return md5_cmn(_^m^f,d,_,r,i,n)}function md5_ii(d,_,m,f,r,i,n){return md5_cmn(m^(_|~f),d,_,r,i,n)}function safe_add(d,_){var m=(65535&d)+(65535&_);return(d>>16)+(_>>16)+(m>>16)<<16|65535&m}function bit_rol(d,_){return d<<_|d>>>32-_}
function tinymd5(str, length) {
length = length || 16;
str = window.btoa(md5(str)).replace(/[aiueoAIUEO\+\/]/g, '').substring(0, length);
if(str.length < length) {
str += Array(length - str.length).join('=');
}
return str;
}
// example usage:
var shortHash = tinymd5(JSON.stringify(someObj), 16);
md5函数来自
tinymd5函数是根据https://rolandeckert.com/notes/md5
代码转换为JavaScript