snaper/cruftflake

This package provides a PHP implementation of Twitter Snoflake ID Generator algoritm

CruftFlake

, _(*1)

A stab at a version of Twitter Snowflake but in PHP with a simple ZeroMQ interface (rather than Thrift)., _(*2)

Implementation

This project was motivated by personal curiosity and also my inability to get Twitter's project to build., _(*3)

The implementation copies Twitter - generating 64 bit IDs., _(*4)

• time - 41 bits
• configured machine ID - 10 bits
• sequence number - 12 bits

Has a custom epoch that means it can generate IDs until 2081-09-06 (not the same epoch as Snowflake)., _(*5)

ZooKeeper for config coordination (optional)

Each machine must have a unique 10 bit machine ID. ZooKeeper can be used to keep a list of all registered machine IDs, allowing new machines to self-assign a new unique machine ID., _(*6)

When using ZooKeeper, when a new node starts up for the first time it must be able to contact the ZooKeeper cluster and create a new node. It will look at all the existing nodes and then (if it can't find its own Mac Address) attempt to claim a free one., _(*7)

I was using Ephemeral nodes for this - similar(ish) to a lock pattern but this had the issue that the node needed to remain connected to ZK throughout its lifetime -- this way it doesn't., _(*8)

The downside is that potentially the 1024 possible machine IDs will "fill up" and need to be manually pruned., _(*9)

Running

Git clone and then execute composer update to install the dependencies. You should run the tests to verify things are OK:, _(*10)

vendor/bin/phpunit

There are two scripts provided for playing about with., _(*11)

1. The generator (the server), _(*12)

   ./examples/cruftflake.php, _(*13)

Or to specify a manually configured machine ID:, _(*14)

./examples/cruftflake.php -m 1

1. A client that will generate N IDs and dump to STDOUT, _(*15)

   ./examples/client.php -n 100, _(*16)