node.js script to generate a hash value using the hash.js and the lodash

utils_hash.js

'use strict';

var _ = require('lodash'),
    toHash = {}
;

//============================================================================//
// hash ids with mininum length = 8
var hashids = (function(){

// https://github.com/ivanakimov/hashids.js
var Hashids=function(){"use strict";function Hashids(salt,minHashLength,alphabet){var uniqueAlphabet,i,j,len,sepsLength,diff,guardCount;this.version="1.0.2";this.minAlphabetLength=16;this.sepDiv=3.5;this.guardDiv=12;this.errorAlphabetLength="error: alphabet must contain at least X unique characters";this.errorAlphabetSpace="error: alphabet cannot contain spaces";this.alphabet="abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890";this.seps="cfhistuCFHISTU";this.minHashLength=parseInt(minHashLength,10)>0?minHashLength:0;this.salt=typeof salt==="string"?salt:"";if(typeof alphabet==="string"){this.alphabet=alphabet}for(uniqueAlphabet="",i=0,len=this.alphabet.length;i!==len;i++){if(uniqueAlphabet.indexOf(this.alphabet.charAt(i))===-1){uniqueAlphabet+=this.alphabet.charAt(i)}}this.alphabet=uniqueAlphabet;if(this.alphabet.length<this.minAlphabetLength){throw this.errorAlphabetLength.replace("X",this.minAlphabetLength)}if(this.alphabet.search(" ")!==-1){throw this.errorAlphabetSpace}for(i=0,len=this.seps.length;i!==len;i++){j=this.alphabet.indexOf(this.seps.charAt(i));if(j===-1){this.seps=this.seps.substr(0,i)+" "+this.seps.substr(i+1)}else{this.alphabet=this.alphabet.substr(0,j)+" "+this.alphabet.substr(j+1)}}this.alphabet=this.alphabet.replace(/ /g,"");this.seps=this.seps.replace(/ /g,"");this.seps=this.consistentShuffle(this.seps,this.salt);if(!this.seps.length||this.alphabet.length/this.seps.length>this.sepDiv){sepsLength=Math.ceil(this.alphabet.length/this.sepDiv);if(sepsLength===1){sepsLength++}if(sepsLength>this.seps.length){diff=sepsLength-this.seps.length;this.seps+=this.alphabet.substr(0,diff);this.alphabet=this.alphabet.substr(diff)}else{this.seps=this.seps.substr(0,sepsLength)}}this.alphabet=this.consistentShuffle(this.alphabet,this.salt);guardCount=Math.ceil(this.alphabet.length/this.guardDiv);if(this.alphabet.length<3){this.guards=this.seps.substr(0,guardCount);this.seps=this.seps.substr(guardCount)}else{this.guards=this.alphabet.substr(0,guardCount);this.alphabet=this.alphabet.substr(guardCount)}}Hashids.prototype.encode=function(){var ret="",i,len,numbers=Array.prototype.slice.call(arguments);if(!numbers.length){return ret}if(numbers[0]instanceof Array){numbers=numbers[0]}for(i=0,len=numbers.length;i!==len;i++){if(typeof numbers[i]!=="number"||numbers[i]%1!==0||numbers[i]<0){return ret}}return this._encode(numbers)};Hashids.prototype.decode=function(hash){var ret=[];if(!hash.length||typeof hash!=="string"){return ret}return this._decode(hash,this.alphabet)};Hashids.prototype.encodeHex=function(str){var i,len,numbers;str=str.toString();if(!/^[0-9a-fA-F]+$/.test(str)){return""}numbers=str.match(/[\w\W]{1,12}/g);for(i=0,len=numbers.length;i!==len;i++){numbers[i]=parseInt("1"+numbers[i],16)}return this.encode.apply(this,numbers)};Hashids.prototype.decodeHex=function(hash){var ret=[],i,len,numbers=this.decode(hash);for(i=0,len=numbers.length;i!==len;i++){ret+=numbers[i].toString(16).substr(1)}return ret};Hashids.prototype._encode=function(numbers){var ret,lottery,i,len,number,buffer,last,sepsIndex,guardIndex,guard,halfLength,excess,alphabet=this.alphabet,numbersSize=numbers.length,numbersHashInt=0;for(i=0,len=numbers.length;i!==len;i++){numbersHashInt+=numbers[i]%(i+100)}lottery=ret=alphabet.charAt(numbersHashInt%alphabet.length);for(i=0,len=numbers.length;i!==len;i++){number=numbers[i];buffer=lottery+this.salt+alphabet;alphabet=this.consistentShuffle(alphabet,buffer.substr(0,alphabet.length));last=this.hash(number,alphabet);ret+=last;if(i+1<numbersSize){number%=last.charCodeAt(0)+i;sepsIndex=number%this.seps.length;ret+=this.seps.charAt(sepsIndex)}}if(ret.length<this.minHashLength){guardIndex=(numbersHashInt+ret[0].charCodeAt(0))%this.guards.length;guard=this.guards[guardIndex];ret=guard+ret;if(ret.length<this.minHashLength){guardIndex=(numbersHashInt+ret[2].charCodeAt(0))%this.guards.length;guard=this.guards[guardIndex];ret+=guard}}halfLength=parseInt(alphabet.length/2,10);while(ret.length<this.minHashLength){alphabet=this.consistentShuffle(alphabet,alphabet);ret=alphabet.substr(halfLength)+ret+alphabet.substr(0,halfLength);excess=ret.length-this.minHashLength;if(excess>0){ret=ret.substr(excess/2,this.minHashLength)}}return ret};Hashids.prototype._decode=function(hash,alphabet){var ret=[],i=0,lottery,len,subHash,buffer,r=new RegExp("["+this.guards+"]","g"),hashBreakdown=hash.replace(r," "),hashArray=hashBreakdown.split(" ");if(hashArray.length===3||hashArray.length===2){i=1}hashBreakdown=hashArray[i];if(typeof hashBreakdown[0]!=="undefined"){lottery=hashBreakdown[0];hashBreakdown=hashBreakdown.substr(1);r=new RegExp("["+this.seps+"]","g");hashBreakdown=hashBreakdown.replace(r," ");hashArray=hashBreakdown.split(" ");for(i=0,len=hashArray.length;i!==len;i++){subHash=hashArray[i];buffer=lottery+this.salt+alphabet;alphabet=this.consistentShuffle(alphabet,buffer.substr(0,alphabet.length));ret.push(this.unhash(subHash,alphabet))}if(this._encode(ret)!==hash){ret=[]}}return ret};Hashids.prototype.consistentShuffle=function(alphabet,salt){var integer,j,temp,i,v,p;if(!salt.length){return alphabet}for(i=alphabet.length-1,v=0,p=0;i>0;i--,v++){v%=salt.length;p+=integer=salt.charAt(v).charCodeAt(0);j=(integer+v+p)%i;temp=alphabet.charAt(j);alphabet=alphabet.substr(0,j)+alphabet.charAt(i)+alphabet.substr(j+1);alphabet=alphabet.substr(0,i)+temp+alphabet.substr(i+1)}return alphabet};Hashids.prototype.hash=function(input,alphabet){var hash="",alphabetLength=alphabet.length;do{hash=alphabet.charAt(input%alphabetLength)+hash;input=parseInt(input/alphabetLength,10)}while(input);return hash};Hashids.prototype.unhash=function(input,alphabet){var number=0,pos,i;for(i=0;i<input.length;i++){pos=alphabet.indexOf(input[i]);number+=pos*Math.pow(alphabet.length,input.length-i-1)}return number};if(typeof define==="function"&&typeof define.amd==="object"&&define.amd){define(function(){return Hashids})}return Hashids}();

var salt = 'this is the salt message';

return new Hashids( salt, 8 );

})();
//============================================================================//

toHash.numbers = function hashNumbers(toEncode){
    return hashids.encode(toEncode);
};

//----------------------------------------------------------------------------//

toHash.complex = function hashComplex( value ) {
    if( !_.isString( value ) ) {value = JSON.stringify( value );}

    var i;
    var charArray = [];

    for( i = value.length - 1; i >= 0; i-- ) {
        charArray.push( value.charCodeAt(i) );
    }

    var hash = hashids.encode( charArray );
    charArray = [];

    var hashSum = hash.length;
    for( i = hash.length - 1; i >= 0; i-- ) {
        hashSum += hash.charCodeAt(i);
    }

    return {
        input: value,
        hashSum: hashSum,
        hash: hashids.encode( hashSum )
    }
};

//----------------------------------------------------------------------------//

toHash.getRandomSizeOfPossible = function getRandomSizeOfPossible(size,possible){
    size = size || 8;
    possible = possible || 'abcdefghijklmnopqrstuvwxyz0123456789';
    var text = '';

    for (var i = 0; i < size; i++) {
        text += possible.charAt(Math.floor(Math.random() * possible.length));
    }

    return text;
};

toHash.getRandomSizeOfNumbers = function getRandomSizeOfNumbers(length){
    return toHash.getRandomSizeOfPossible(
        length, '1234567890987654321'
    );
};

toHash.generateRandomHash = function generateRandomHash() {
    return toHash.getRandomSizeOfPossible();
};

//----------------------------------------------------------------------------//

module.exports = toHash;