snowflake-srv

Snowflake

Snowflake is a network service for generating unique ID numbers at high scale with some simple guarantees. http://twitter.com/ This is a go language version based on Consul KV

Getting started

1. Install Consul

   Consul is the default registry/discovery for go-micro apps. It's however pluggable. https://www.consul.io/intro/getting-started/install.html

2. Run Consul

   $ consul agent -server -bootstrap-expect 1 -data-dir /tmp/consul
   

3. Download and start the service

   go get github.com/unicok/snowflake-srv
   ./snowflake-srv
   

The API

• GetUUID
• Next

UUID:

• unused - 1 bit

• time - 41 bits (millisecond precision w/ a custom epoch gives us 69 years)

• configured machine id - 10 bits - gives us up to 1024 machines

• sequence number - 12 bits - rolls over every 4096 per machine (with protection to avoid rollover in the same ms)

  |-- UNUSED(1BIT) --|-- TIMESTAMP(41BIT) --|-- MACHINE-ID(10BIT) --|-- SERIAL-NO(12BIT) --|