1.1.0. All functions allow you specify a string of valid characters in case you do not want the default of 0-9A-Z excluding vowels and Y. Callbacks can still be sent. All results are still Uppercase.
Note that the characters must be in same order when you are validating. A random string generated with sequence '0123456789' will not validate correctly against sequence '9876543210'.

#### Advantages
1. Strings have a checksum character at the end.
2. Avoid Bad words in generated string by removing A,E,I,O,U,Y
3. Random strings are cryptographically generated (dependent on node's crypto library)
4. Provide your own character sequence

Installation

Usage

// to generate a 16-digit checksummed string
var str = Luhn.random(16);
console.log(str);

// to generate a 16-digit checksummed string with 0123456789 as sequence
// Method 1
var res = Luhn.random(16, '0123456789');
console.log(res);
console.log(Luhn.check(res, '0123456789'));

// Method 2
var creator = new Luhn('0123456789');
res = creator.random(16);
console.log(res);
console.log(creator.check(res));

// to test a string for checksum validity
var chk = Luhn.check('30MFLRQDVCFQ9SK1');
var valid = chk.result;
var validityerror = chk.error;

// Use callbacks
Luhn.random(16, function(error, result){
if(error){
// do something with error...
return;
}
console.log(result);
});

Luhn.check('LH989002BW3P', function(error, result){
if(error){
// do something with error...
return;
}
console.log(result); // true or false
});