Repository files navigation

MsgFlo is a distributed, polyglot FBP (flow-based-programming)runtime. It integrates with other FBP tools like theFlowhub visual programming IDE.

This library makes it easy to create MsgFlo participants in JavaScript/CoffeScript on node.js.

Production

• Used atTheGrid for all workers using AMQP/RabbitMQ,including inimgflo-server
• Also used bynoflo-runtime-msgflo
• Experimental support for MQTT and direct transports

MIT, see./LICENSE

Add as an NPM dependency

npm install --save msgflo-nodejs

A simple participant (CoffeeScript)

msgflo = require 'msgflo-nodejs'RepeatParticipant = (client, role) ->  definition =    component: 'Repeat'    icon: 'file-word-o'    label: 'Repeats in data without changes'    inports: [      id: 'in'      type: 'any'    ]    outports: [      id: 'out'      type: 'any'    ]  process = (inport, indata, callback) ->    return callback 'out', null, indata  return new msgflo.participant.Participant client, definition, process, roleclient = msgflo.transport.getClient 'amqp://localhost'worker = RepeatParticipant client, 'repeater'worker.start (err) ->  throw err if err  console.log 'Worker started'

If you expose the participant factory function (examples/Repeat.coffee)

module.exports = RepeatParticipant

Then you can use themsgflo-nodejs exectutable to start participant

msgflo-nodejs --name repeater ./examples/Repeat.coffee

msgflo-nodejs uses thedebug NPM module.You can enable (all) logging using:

export DEBUG=msgflo*

msgflo-nodejs has a transport abstraction layer. So to support a new messaging system,implementClient andMessageBrokerinterfaces.

You can then pass the Client instance into aParticipant.

Or you can register a new transport usingmsgflo.transport.register('mytransport', myTransportModule).Then you can get a Client instance usingmsgflo.transport.getClient('mytransport://somehost:666').This has the advantage of also working when specifying the broker URL usingmsgflo-nodejs --broker orMSGFLO_BROKER= environment variable.