Snowflake4s

A k-sortable unique ID generation lib using Scala.

Snowflake4s can generate the roughly-sorted 64 bits ids as Long type written by Scala. The name of this lib was inspired by a project from Twitter called "Snowflake". So it's using the same encoded ID format as Twitter's Snowflake, but Snowflake4s providing the easier way to use Snowflake schema.

Get Started

You should add the following dependency.

resolvers +=
  "Sonatype OSS Snapshots" at "https://s01.oss.sonatype.org/content/repositories/snapshots"

libraryDependencies += "io.github.flintersvn" %% "snowflake4s" % "0.1.0-SNAPSHOT"

Add manual config to application.conf:

snowflake4s {
  twitter { # using Twitter's algorithm
    machine_id = 1 # from 0 to 31
    machine_id = ${?SNOWFLAKE4S_MACHINE_ID} # Set machine id from env
    
    worker_id = 1 # from 0 to 31 
    worker_id = ${?SNOWFLAKE4S_WORKER_ID} # Set worker id from env

    # Default Epoch is October 18, 1989, 16:53:40 UTC
    # You can change to a different epoch by below setting
    # epoch = "2021-01-01T00:00:00Z" 
  }
}

How to use

to generate id:

val IdGenerator = Snowflake4s.generator

val id = IdGenerator.generate()
id.toBase62 // 52nlGCNq00n
id.toLong // 4234436103643992065

// Revert info from saved Id

val id = Id.fromBase62("52nlGCNq00n")
println(id.workerId) // 5

You also could bulk generate 10 ids with the following snippet:

val IdGenerator = Snowflake4s.generator

val ids = IdGenerator.bulkGenerate(10)

License

The Snowflake4s is released under version 2.0 of the Apache License.

References

• Slide:
  • https://www.slideshare.net/nguyentungniit/distributed-unique-id-generation
• Twitter Snowflake
  • https://github.com/twitter/snowflake/tree/scala_28
  • https://blog.twitter.com/2010/announcing-snowflake
• K-ordered
  • http://www.geeksforgeeks.org/nearly-sorted-algorithm/