blt

Storm Bolts without the overhead.

Example

var through = require('through2')
var createBolt = require('blt')
 
createBolt(splitSentence)
 
function splitSentence(configuration) {
  var splitStream = through.obj(splitWords)
 
  return splitStream
 
  function splitWords(obj, _, next) {
    obj.tuple[0].split(' ').forEach(function(word) {
      splitStream.push(word)
    })
 
    splitStream.emit('ack', obj)
 
    next()
  }
}

API

blt(createStream, _opts)

• createStream is a function that can be called with a configuration object and returns a Duplex Stream.

• _opts is an optional configuration object accepting options:

  • anchored - a Boolean indicating whether you prefer this bolt to provide anchors to Storm.

• blt will write tuple objects directly to the returned stream.

• If anchored is true, the stream is expected to stream arrays of form: [data, tuples], where data is the data to emit, and tuples is the Storm tuple(s) that it is anchored to.

Events

• When your stream emits data, blt emits the data packaged up in Storm's tuple format with all of the applicable anchoring data.
• If your stream emits a "log" event with an argument, blt passes it along to Storm as a "log" event with that argument.
• If your stream emits a "fail" event with the relevant tuple, blt will "fail" for you.
• If your stream emits an "ack" event with the relevant tuple, blt will "ack" for you.

Usage

blt handles all of the Storm-specific aspects of constructing Bolt streams for Storm.

• Creates PID file and handshakes with Storm at startup.
• Handles responding to heartbeats.

Notes

• This is experimental and relatively untested, use at your own risk!
• This module is somewhat optimized for a simplified use-case, if you need more, try storm-stream or node-storm.
• For a more magical approach, check out garlic.

License

MIT