nsolid-manager/nsolid/console/src/cli.js

A manager that sets up and runs N|Solid for you

import fs from 'fs'
import rimraf from 'rimraf'

import collect from '../src/collect'
import config from '../src/collect/config'
import Cache from '../src/collect/cache'

// Get config from process.argv
const conf = config(process.argv)

/**
 * Configure Storage
 */

// IIFE required so we can use return to short-circuit
;(function start () {
  if (!conf.storage) {
    return onError(new Error('--storage is required'))
  }

  if (conf.flush) {
    // flush persistence dirs if passed --flush
    flushDir(conf.storage)
    flushDir(conf.record)
  }

  // current state cache
  const cache = new Cache(conf.storage)

  cache.restore(e => {
    if (e && !conf.flush) console.warn('could not load existing cache, starting over')

    /**
     * Start polling
     */

    const pollingEmitter = collect.poll(conf, cache)

    /**
     * Record hub results on disk
     */

    if (conf.record) {
      pollingEmitter.on('output', obj => {
        fs.appendFile(conf.record, JSON.stringify(obj) + '\n', err => {
          if (err) onError(err)
        })
      })
    }

    /**
     * Boot server
     */

    collect.createServer(conf, pollingEmitter, cache, onError)
    .on('listening', function (err) {
      if (err) return onError(err)
      const listening = this.address()
      console.info('Server running on http://%s:%s', listening.address, listening.port)
    })
  })
})()

/**
 * Wipe a directory.
 * Does nothing if dir is not a string or accessible.
 */

function flushDir (dir) {
  if (!dir || typeof dir !== 'string') return

  try {
    fs.accessSync(dir)
  } catch (err) {
    // ignore err, just return if can't access
    return
  }

  console.info('flushing', dir)
  rimraf.sync(dir)
}

/**
 * Generic CLI Errback handler
 */

function onError (err) {
  if (!err) return
  console.error(err.stack || err)

  // add helpful suggestions here
  if (err.code === 'EACCES') {
    console.error('\nHave you configured a writable --storage directory?')
  }

  console.error('\nRun `nsolid-console --help` for command-line help.')
  process.exit(1)
}