botium-core/src/helpers/SyslogServer.js

The Selenium for Chatbots

const dgram = require('dgram')
const EventEmitter = require('events')

function createErrorObject (err, message) {
  return {
    date: new Date(),
    error: err,
    message: message
  }
}

module.exports = class SyslogServer extends EventEmitter {
  constructor () {
    super()
    this.status = false
    this.server = null
  }

  start (options = { port: 514, address: '0.0.0.0', exclusive: true }, cb) {
    return new Promise((resolve, reject) => {
      if (this.status === true) {
        const errorObj = createErrorObject(null, 'NodeJS Syslog Server is already running!')
        if (cb) return cb(errorObj)
        return reject(errorObj)
      } else {
        this.server = dgram.createSocket('udp4')

        // Socket listening handler
        this.server.on('listening', () => {
          this.status = true
          this.emit('start')
        })

        // Socket error handler
        this.server.on('error', (err) => {
          this.emit('error', err)
        })

        // Socket message handler
        this.server.on('message', (msg, remote) => {
          const message = {
            date: new Date(),
            host: remote.address,
            message: msg.toString('utf8'),
            protocol: remote.family
          }
          this.emit('message', message)
        })

        // Socket close handler
        this.server.on('close', () => {
          this.status = false
          this.emit('stop')
        })

        this.server.bind(options, (err) => {
          if (err) {
            const errorObj = createErrorObject(err, 'NodeJS Syslog Server failed to start!')
            if (cb) return cb(errorObj)
            return reject(errorObj)
          } else {
            if (cb) return cb()
            return resolve()
          }
        })
      }
    })
  }

  stop (cb) {
    return new Promise((resolve, reject) => {
      try {
        this.server.close(() => {
          if (cb) return cb()
          return resolve()
        })
      } catch (err) {
        const errorObj = createErrorObject(err, 'NodeJS Syslog Server is not running!')
        if (cb) return cb(errorObj)
        return reject(errorObj)
      }
    })
  }

  isRunning () {
    return this.status
  }
}