rholder / fauxflake Goto Github PK

For some reason whenever I run an application using fauxflake inside a docker,
it always generates the same id (this is a single long running instance of a linux container),
even if the container stays up and has net=host set.

private static IdGenerator snowflake = IdGenerators.newSnowflakeIdGenerator();
snowflake.generateId(1000).asString();

always yields ffffffffffc01000

works perfectly outside the container though.

Complete testing of Netflix-style Gradle build, and push it to Maven Central.

Currently, when backwards time is detected it is propagated up as an InterruptedException.

Add examples and prepare README.md for 1.0.0 release.

Currently, when we exceed the specified wait time, it is propagated up as an InterruptedException.

'nuff said.

Negative machine IDs are possible, and SnowflakeEncodingProvider left-shifts these without checking, resulting in a small negative number that is OR'ed with the timestamp, erasing the timestamp. Example:

    static class FixedIdProvider implements MachineIdProvider {
        final long id;
        FixedIdProvider(long id) {
            this.id = id;
        }
        public long getMachineId() {
            return id;
        }
    }

    public static void main(String[] args) throws Exception
    {
        IdGenerator g1 = newSnowflakeIdGenerator(new FixedIdProvider(1));
        System.out.println(g1.generateId(0).asString());
        IdGenerator g2 = newSnowflakeIdGenerator(new FixedIdProvider(-1));
        System.out.println(g2.generateId(0).asString());
    }

Output:

080f6b18b1001000
fffffffffffff000

Creating a wrapper on e.g. MacPidMachineIdProvider is an easy temporary workaround.

I was a bit surprised to see that this code in a unit test produces two duplicates:

        IdGenerator snowflake = IdGenerators.newSnowflakeIdGenerator();
        for (int i = 0; i < 10; i++) {
            String id = snowflake.generateId(1000).asString();
            System.out.println(id);
        }

output:

ffffffffffed8000
ffffffffffed8000
ffffffffffed8001
ffffffffffed8002
ffffffffffed8003
ffffffffffed8004
ffffffffffed8005
ffffffffffed8006
ffffffffffed8000
ffffffffffed8001