swift_ids

Description:

swift ids

swift_ids #
Convert numeric IDs to human and web friendly string and back.



integer
swift_id




0
GX08


1
HY9U


2
JA2Q


5
D9YU


1000
SF7B


10000000
GM1Y3Q



features of generated id #

easy to write down / spell over the phone because generated string uses:

only uppercase letters,
no confusing digits: O=0 and I=L=1
no two consecutive characters are the same


fast to convert back and forth (algorithm uses mostly binary operations)
seems random (user can't browse trough entities easily or tell how many entities there are)
generated id is shorter than original int as decimal (5 characters can save 8388608 ids)
free from accidental profanities (and words in general)
minimum length and initial zero code is configurable

usage #
var encode = new Id(5);
print("${encode.value} == ${encode.toString()}"); //5 == D9YU
var decode = new Id.fromString('D9YU');
print("${decode.value} == ${decode.toString()}"); //4 == C84X

var encode2 = new Id(5, minLength:10, zero:0x55555555555);
print("${encode2.value} == ${encode2.toString()}"); //5 == HBQ8H7E85B
//same zero/minLength need to be used when decoding
var decode2 = new Id.fromString('HBQ8H7E85B', minLength:10, zero:0x55555555555);
print("${decode2.value} == ${decode2.toString()}"); //4 == C84X

//you can also create single converter instance to encode ints and decode Strings:
var converter = new IdConverter(minLength: 9, zero: 0x1234512345);
converter.decode('5S4YD9X01'); //101
converter.encode(101); //'5S4YD9X01'

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zero is an initial value that is XORed with input that can be used to:

make separate entities ids not overlap (so user with id=5 won't have same hash as message with id=5)
mangle initial integer to prevent repetitions for small integers with large minLength
zero should have maximum (5 * minLength) - (2 * (minLength / 3)) bits.