fantomex v0.0.1

Fantomex

Fantomex was created by the Weapon Plus Program to serve as a super-sentinel against Earth's mutant population. He was born in the World, a secret square mile of experimental micro-reality built by the military industrial complex. The Weapon Plus scientists heated up time itself until it flowed in all directions at once. Into this pliant, fast-moving substance, they introduced human test groups, whose genetic material was crudely spliced with adaptive Nano-Sentinel technology, and ran the result through half a million years of cyborg mutation in eighteen months.

Intro

Fantomex is a lib for storing a relatively small number of background jobs in a persistent queue. It's designed as a way for a single Redis pub/sub or ZeroMQ worker to store incoming messages in case of a crash. If Fantomex is tracking 10,000 jobs, you should probably look into fixing your workers or adding more to handle the load.

A lot of inspiration came from the design of Resque and Delayed Job, but there are a few key features that Fantomex needs.

• Use isolated databases scoped to the worker, not central databases like Redis or MySQL. Prefer sqlite, kyoto cabinet, leveldb, etc.
• Allow the requeueing of errored jobs. Fantomex jobs should always be run.
• Errored jobs are re-queued to be run after a delay (with exponential backoff).

Usage

First, you'll want to create a Fantomex instance with a sqlite backend.

var fantomex = require('fantomex')

// defaults to `process.cwd() + "/queue.db"`
var store = fantomex.sqlite("/path/to/queue.db")

Add an event listener to handle Fantomex messages (in case the worker is restarting after a crash and there is a backlog).

// Emits the message that was received.  Whatever happens, Fantomex
// should either remove the message or requeue it, so it can 
store.on("message", function(msg, next) {
  try {
    // do it for the logs
    console.time("message")
    doSomethingTo(msg)
    next() // all done!
  } catch(e) {
    console.log("Error:")
    console.log(e)
    next(e) // track the error
  } finally {
    console.timeEnd("message")
  }
})

Next, add items to the queue as they come in from ZeroMQ (or wherever).

// this could be a ZeroMQ socket, or some other clever lib that
// emits messages.  Doesn't realprocess.cwd()ly matter to Fantomex.
queue.on("message", function(msg) {
  store.push(msg) // calls toString()
})

TODO

• Investigate other databases (Kyoto Cabinet, LevelDB, Redis, etc).
• Investigate abstract SQL interface so sqlite support means mysql/postgres also work.

Status

Alpha.