node-redis/test/lib/stunnel-process.js

'use strict'

// helper to start and stop the stunnel process.
var spawn = require('child_process').spawn
var EventEmitter = require('events')
var fs = require('fs')
var path = require('path')
var util = require('util')

function once (cb) {
  var called = false
  return function () {
    if (called) return
    called = true
    cb.apply(this, arguments)
  }
}

function StunnelProcess (confDir) {
  EventEmitter.call(this)

  // set up an stunnel to redis; edit the conf file to include required absolute paths
  var confFile = path.resolve(confDir, 'stunnel.conf')
  var confText = fs.readFileSync(confFile + '.template').toString().replace(/__dirname,/g, confDir)

  fs.writeFileSync(confFile, confText)
  var stunnel = this.stunnel = spawn('stunnel', [confFile])

  // handle child process events, and failure to set up tunnel
  var self = this
  this.timer = setTimeout(function () {
    self.emit('error', new Error('Timeout waiting for stunnel to start'))
  }, 8000)

  stunnel.on('error', function (err) {
    self.clear()
    self.emit('error', err)
  })

  stunnel.on('exit', function (code) {
    self.clear()
    if (code === 0) {
      self.emit('stopped')
    } else {
      self.emit('error', new Error('Stunnel exited unexpectedly; code = ' + code))
    }
  })

  // wait to stunnel to start
  stunnel.stderr.on('data', function (data) {
    if (data.toString().match(/Service.+redis.+bound/)) {
      clearTimeout(this.timer)
      self.emit('started')
    }
  })
}
util.inherits(StunnelProcess, EventEmitter)

StunnelProcess.prototype.clear = function () {
  this.stunnel = null
  clearTimeout(this.timer)
}

StunnelProcess.prototype.stop = function (done) {
  if (this.stunnel) {
    this.stunnel.kill()
  }
}

module.exports = {
  start: function (done, confDir) {
    done = once(done)
    var stunnel = new StunnelProcess(confDir)
    stunnel.once('error', done.bind(done))
    stunnel.once('started', done.bind(done, null, stunnel))
  },
  stop: function (stunnel, done) {
    stunnel.removeAllListeners()
    stunnel.stop()
    stunnel.once('error', done.bind(done))
    stunnel.once('stopped', done.bind(done, null))
  }
}