maxcountryman/flake

Decentralized, k-ordered unique IDs in Clojure

flake's Issues

base 62 alphabet order

The alphabet order is incorrect for proper sorting.

Current:
"0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"

Should be:
"0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz"

Possible sort issue for times approaching 1970

When base-encoding the bigint:

Since the "left" 64 bits are using milliseconds since epoch, and are technically allowed to go up to a value of (Long/MAX_VALUE), and also go down to zero, the character count of the final encoded bigint value can be as many as 22, but also much lower (if I've interpreted the source correctly).

Assuming the goal is always ensuring proper sort order, the value needs to left-padded with "0"s to the max character length (22 if I'm not mistaken).

Increase time precision?

Great library, and I know this is a port, but I'd like to see support for 100-nanosecond precision (where available). I noticed you are utilizing nanoTime now.

I don't know the rationale of having the MAC/machine ID in the middle, but this would seem to provide ordering with more precision: [millis-timestamp:64][100nano+sequence:16][MAC:48]

You could provide up to 100 nano precision with the same bits (consistent with UUID-1)... and where the precision lacks the sequence is used to fill in any remaining bits.

Any thoughts?

Will throw an exception if generating more than 65,535 flakes in a millisecond

While it is very unlikely to happen, if 65,535 flakes are generated in a millisecond, then an exception will be thrown. Would it be better to check this and wait until the start of the next millisecond to generate the next flake?

I'm not 100% sure this is even an issue, if the caller is aware that this may throw an exception then they could prepare for it and catch it to retry.

(PartialFlake. (System/currentTimeMillis) (p/inc (Short/MAX_VALUE)))
IllegalArgumentException Value out of range for short: 32768  clojure.lang.RT.shortCast (RT.java:1040)