Merge pull request #2 from vatesfr/v0.8.x

Refactor on top of jsonrpc-websocket-client

packages/xo-lib/.babelrc

@@ -0,0 +1,8 @@
+{
+  "comments": false,
+  "compact": true,
+  "presets": [
+    "stage-0",
+    "es2015"
+  ]
+}

packages/xo-lib/.editorconfig

@@ -1,12 +1,65 @@
-# EditorConfig is awesome: http://EditorConfig.org
+# http://EditorConfig.org
+#
+# Julien Fontanet's configuration
+# https://gist.github.com/julien-f/8096213
 
-# top-most EditorConfig file
+# Top-most EditorConfig file.
 root = true
 
+# Common config.
 [*]
 charset = utf-8
 end_of_line = lf
-indent_size = 2
-indent_style = space
 insert_final_newline = true
 trim_trailing_whitespaces = true
+
+# CoffeeScript
+#
+# https://github.com/polarmobile/coffeescript-style-guide/blob/master/README.md
+[*.{,lit}coffee]
+indent_size = 2
+indent_style = space
+
+# Markdown
+[*.{md,mdwn,mdown,markdown}]
+indent_size = 4
+indent_style = space
+
+# Package.json
+#
+# This indentation style is the one used by npm.
+[/package.json]
+indent_size = 2
+indent_style = space
+
+# Jade
+[*.jade]
+indent_size = 2
+indent_style = space
+
+# JavaScript
+#
+# Two spaces seems to be the standard most common style, at least in
+# Node.js (http://nodeguide.com/style.html#tabs-vs-spaces).
+[*.js]
+indent_size = 2
+indent_style = space
+
+# Less
+[*.less]
+indent_size = 2
+indent_style = space
+
+# Sass
+#
+# Style used for http://libsass.com
+[*.s[ac]ss]
+indent_size = 2
+indent_style = space
+
+# YAML
+#
+# Only spaces are allowed.
+[*.yaml]
+indent_size = 2
+indent_style = space

packages/xo-lib/.gitignore

@@ -1 +1,9 @@
-/node_modules/
+/.nyc_output/
+/bower_components/
+/dist/
+
+npm-debug.log
+npm-debug.log.*
+
+!node_modules/*
+node_modules/*/

packages/xo-lib/.mocha.js

@@ -0,0 +1,5 @@
+Error.stackTraceLimit = 100
+
+try { require('trace') } catch (_) {}
+try { require('clarify') } catch (_) {}
+try { require('source-map-support/register') } catch (_) {}

packages/xo-lib/.mocha.opts

@@ -0,0 +1 @@
+--require ./.mocha.js

packages/xo-lib/.npmignore

@@ -1 +1,10 @@
+/examples/
+example.js
+example.js.map
+*.example.js
+*.example.js.map
+
+/test/
+/tests/
 *.spec.js
+*.spec.js.map

packages/xo-lib/.travis.yml

@@ -1,5 +1,10 @@
 language: node_js
 node_js:
+  - 'stable'
+  - '4'
+  - '0.12'
   - '0.10'
-  - '0.11'
-  - iojs
+
+# Use containers.
+# http://docs.travis-ci.com/user/workers/container-based-infrastructure/
+sudo: false

packages/xo-lib/api.js

@@ -1,151 +0,0 @@
-'use strict'
-
-// ===================================================================
-
-var Bluebird = require('bluebird')
-var EventEmitter = require('events').EventEmitter
-var eventToPromise = require('event-to-promise')
-var inherits = require('util').inherits
-var MethodNotFound = require('json-rpc-peer').MethodNotFound
-var Peer = require('json-rpc-peer').default
-var startsWith = require('lodash.startswith')
-var WebSocket = require('ws')
-
-var ConnectionError = require('./connection-error')
-var fixUrl = require('./fix-url')
-
-// ===================================================================
-
-function getCurrentUrl () {
-  /* global window: false */
-
-  if (typeof window === 'undefined') {
-    throw new Error('cannot get current URL')
-  }
-
-  return String(window.location)
-}
-
-function makeDeferred () {
-  var resolve, reject
-  var promise = new Bluebird(function (resolve_, reject_) {
-    resolve = resolve_
-    reject = reject_
-  })
-
-  return {
-    promise: promise,
-    reject: reject,
-    resolve: resolve
-  }
-}
-
-function noop () {}
-
-// -------------------------------------------------------------------
-
-// Low level interface to XO.
-function Api (url) {
-  // Super constructor.
-  EventEmitter.call(this)
-
-  // Fix the URL (ensure correct protocol and /api/ path).
-  this._url = fixUrl(url || getCurrentUrl())
-
-  // Will contains the connection promise.
-  this._connection = null
-
-  // Will contains the WebSocket.
-  this._socket = null
-
-  // The JSON-RPC server.
-  var this_ = this
-  this._jsonRpc = new Peer(function (message) {
-    if (message.type === 'notification') {
-      this_.emit('notification', message)
-    } else {
-      // This object does not support requests.
-      throw new MethodNotFound(message.method)
-    }
-  }).on('data', function (message) {
-    this_._socket.send(message)
-  })
-}
-inherits(Api, EventEmitter)
-
-Api.prototype.close = function () {
-  var socket = this._socket
-  if (socket) {
-    socket.close()
-
-    console.log(socket.readyState)
-    if (socket.readyState !== 3) {
-      return eventToPromise(socket, 'close').then(noop)
-    }
-  }
-
-  return Bluebird.resolve()
-}
-
-Api.prototype.connect = function () {
-  if (this._connection) {
-    return this._connection
-  }
-
-  var deferred = makeDeferred()
-  this._connection = deferred.promise
-
-  var opts = {}
-  if (startsWith(this._url, 'wss')) {
-    // Due to imperfect TLS implementation in XO-Server.
-    opts.rejectUnauthorized = false
-  }
-  var socket = this._socket = new WebSocket(this._url, '', opts)
-
-  // Used to avoid binding listeners to this object.
-  var this_ = this
-
-  // When the socket opens, send any queued requests.
-  socket.addEventListener('open', function () {
-    // Resolves the promise.
-    deferred.resolve()
-
-    this_.emit('connected')
-  })
-
-  socket.addEventListener('error', function (error) {
-    this_._connection = null
-    this_._socket = null
-
-    // Fails the connect promise if possible.
-    deferred.reject(error)
-  })
-
-  socket.addEventListener('message', function (message) {
-    this_._jsonRpc.write(message.data)
-  })
-
-  socket.addEventListener('close', function () {
-    this_._connection = null
-    this_._socket = null
-
-    this_._jsonRpc.failPendingRequests(new ConnectionError())
-
-    // Only emit this event if connected before.
-    if (deferred.promise.isFulfilled()) {
-      this_.emit('disconnected')
-    }
-  })
-
-  return deferred.promise
-}
-
-Api.prototype.call = function (method, params) {
-  var jsonRpc = this._jsonRpc
-
-  return this.connect().then(function () {
-    return jsonRpc.request(method, params)
-  })
-}
-
-module.exports = Api

packages/xo-lib/back-off.js

@@ -1,76 +0,0 @@
-'use strict'
-
-// ===================================================================
-
-var Bluebird = require('bluebird')
-
-// ===================================================================
-
-function returnThis () {
-  /* jshint validthis: true */
-
-  return this
-}
-
-// Returns an iterator to the Fibonacci sequence.
-function fibonacci (start) {
-  var prev = 0
-  var curr = start || 1
-
-  var iterator = {
-    next: function () {
-      var tmp = curr
-      curr += prev
-      prev = tmp
-
-      return {
-        done: false,
-        value: prev
-      }
-    }
-  }
-
-  // Make the iterator a true iterable (ES6).
-  if (typeof Symbol !== 'undefined') {
-    iterator[Symbol.iterator] = returnThis
-  }
-
-  return iterator
-}
-
-// ===================================================================
-
-function defaultGenerator () {
-  return fibonacci(1e3)
-}
-
-function BackOff (opts) {
-  if (!opts) {
-    opts = {}
-  }
-
-  this._attempts = 0
-  this._generator = opts.generator || defaultGenerator
-  this._iterator = this._generator()
-  this._maxAttempts = opts.maxAttempts || Infinity
-}
-
-BackOff.prototype.wait = function () {
-  var maxAttempts = this._maxAttempts
-  if (this._attempts++ > maxAttempts) {
-    return Bluebird.reject(new Error(
-      'maximum attempts reached (' + maxAttempts + ')'
-    ))
-  }
-
-  return Bluebird.delay(this._iterator.next().value)
-}
-
-BackOff.prototype.reset = function () {
-  this._attempts = 0
-  this._iterator = this._generator()
-}
-
-// ===================================================================
-
-module.exports = BackOff

packages/xo-lib/cli.js

@@ -1,53 +0,0 @@
-#!/usr/bin/env node
-
-'use strict'
-
-var Bluebird = require('bluebird')
-var createRepl = require('repl').start
-var eventToPromise = require('event-to-promise')
-var pw = require('pw')
-
-var Xo = require('./').Xo
-
-// ===================================================================
-
-var usage = ''
-
-function main (args) {
-  if (args[0] === '--help' || args[0] === 'h') {
-    return usage
-  }
-
-  var xo = new Xo(args[0])
-
-  return new Bluebird(function (resolve) {
-    process.stdout.write('Password: ')
-    pw(resolve)
-  }).then(function (password) {
-    return xo.signIn({
-      email: args[1],
-      password: password
-    })
-  }).then(function () {
-    var repl = createRepl({})
-    repl.context.xo = xo
-
-    // Make the REPL waits for promise completion.
-    var evaluate = Bluebird.promisify(repl.eval)
-    repl.eval = function (cmd, context, filename, cb) {
-      evaluate(cmd, context, filename)
-        // See https://github.com/petkaantonov/bluebird/issues/594
-        .then(function (result) { return result })
-        .nodeify(cb)
-    }
-
-    return eventToPromise(repl, 'exit')
-  })
-}
-module.exports = main
-
-// ===================================================================
-
-if (!module.parent) {
-  require('exec-promise')(main)
-}

packages/xo-lib/connection-error.js

@@ -1,9 +0,0 @@
-'use strict'
-
-// ===================================================================
-
-var makeError = require('make-error')
-
-// ===================================================================
-
-module.exports = makeError('ConnectionError')

packages/xo-lib/fix-url.js

@@ -1,21 +0,0 @@
-'use strict'
-
-// ===================================================================
-
-// Fix URL if necessary.
-var URL_RE = /^(?:(?:http|ws)(s)?:\/\/)?(.*?)\/*(?:\/api\/)?(\?.*?)?(?:#.*)?$/
-function fixUrl (url) {
-  var matches = URL_RE.exec(url)
-  var isSecure = !!matches[1]
-  var hostAndPath = matches[2]
-  var search = matches[3]
-
-  return [
-    isSecure ? 'wss' : 'ws',
-    '://',
-    hostAndPath,
-    '/api/',
-    search
-  ].join('')
-}
-module.exports = fixUrl

packages/xo-lib/fix-url.spec.js

@@ -1,48 +0,0 @@
-'use strict'
-
-// ===================================================================
-
-var expect = require('must')
-
-// ===================================================================
-
-/* eslint-env mocha */
-
-describe('fixUrl()', function () {
-  var fixUrl = require('./fix-url')
-
-  describe('protocol', function () {
-    it('is added if missing', function () {
-      expect(fixUrl('localhost/api/')).to.equal('ws://localhost/api/')
-    })
-
-    it('HTTP(s) is converted to WS(s)', function () {
-      expect(fixUrl('http://localhost/api/')).to.equal('ws://localhost/api/')
-      expect(fixUrl('https://localhost/api/')).to.equal('wss://localhost/api/')
-    })
-
-    it('is not added if already present', function () {
-      expect(fixUrl('ws://localhost/api/')).to.equal('ws://localhost/api/')
-      expect(fixUrl('wss://localhost/api/')).to.equal('wss://localhost/api/')
-    })
-  })
-
-  describe('/api/ path', function () {
-    it('is added if missing', function () {
-      expect(fixUrl('ws://localhost')).to.equal('ws://localhost/api/')
-      expect(fixUrl('ws://localhost/')).to.equal('ws://localhost/api/')
-    })
-
-    it('is not added if already present', function () {
-      expect(fixUrl('ws://localhost/api/')).to.equal('ws://localhost/api/')
-    })
-
-    it('removes the hash part', function () {
-      expect(fixUrl('ws://localhost/#foo')).to.equal('ws://localhost/api/')
-    })
-
-    it('conserve the search part', function () {
-      expect(fixUrl('ws://localhost/?foo')).to.equal('ws://localhost/api/?foo')
-    })
-  })
-})

packages/xo-lib/index.js

@@ -1,7 +0,0 @@
-'use strict'
-
-// Expose Bluebird for now to ease integration (e.g. with Angular.js).
-exports.setScheduler = require('bluebird').setScheduler
-
-exports.Api = require('./api')
-exports.Xo = require('./xo')

packages/xo-lib/package.json

@@ -1,12 +1,15 @@
 {
   "name": "xo-lib",
-  "version": "0.7.4",
+  "version": "0.8.0-1",
+  "license": "ISC",
   "description": "Library to connect to XO-Server",
   "keywords": [
     "xen",
     "orchestra",
     "xen-orchestra"
   ],
+  "homepage": "https://github.com/vatesfr/xo-lib",
+  "bugs": "https://github.com/vatesfr/xo-lib/issues",
   "repository": {
     "type": "git",
     "url": "https://github.com/vatesfr/xo-lib"
@@ -15,31 +18,48 @@
     "name": "Julien Fontanet",
     "email": "julien.fontanet@vates.fr"
   },
+  "preferGlobal": false,
+  "main": "dist/",
+  "bin": {},
+  "files": [
+    "dist/"
+  ],
   "engines": {
-    "node": ">=0.8.0"
-  },
-  "scripts": {
-    "lint": "standard",
-    "posttest": "npm run lint",
-    "test": "mocha \"*.spec.js\""
+    "node": ">=0.12"
   },
   "dependencies": {
-    "bluebird": "^2.9.6",
-    "event-to-promise": "^0.4.0",
-    "exec-promise": "^0.5.1",
-    "json-rpc-peer": "^0.11.0",
-    "lodash.assign": "^3.0.0",
-    "lodash.foreach": "^3.0.1",
-    "lodash.isstring": "^3.0.0",
-    "lodash.startswith": "^3.0.0",
-    "make-error": "^1.0.4",
-    "pw": "0.0.4",
-    "ws": "^0.8.0",
-    "xo-collection": "^0.4.0"
+    "jsonrpc-websocket-client": "0.0.1-5",
+    "lodash.startswith": "^4.0.0",
+    "make-error": "^1.0.4"
   },
   "devDependencies": {
-    "mocha": "^2.1.0",
+    "babel-cli": "^6.3.17",
+    "babel-eslint": "^6.0.4",
+    "babel-preset-es2015": "^6.3.13",
+    "babel-preset-stage-0": "^6.3.13",
+    "clarify": "^1.0.5",
+    "dependency-check": "^2.5.1",
+    "mocha": "^2.3.4",
     "must": "^0.13.1",
-    "standard": "^5.3.1"
+    "nyc": "^6.1.1",
+    "source-map-support": "^0.4.0",
+    "standard": "^6.0.8",
+    "trace": "^2.0.1"
+  },
+  "scripts": {
+    "build": "NODE_ENV=production babel --source-maps --out-dir=dist/ src/",
+    "depcheck": "dependency-check ./package.json",
+    "dev": "babel --watch --source-maps --out-dir=dist/ src/",
+    "dev-test": "mocha --opts .mocha.opts --watch --reporter=min \"dist/**/*.spec.js\"",
+    "lint": "standard",
+    "posttest": "npm run lint && npm run depcheck",
+    "prepublish": "npm run build",
+    "test": "nyc mocha --opts .mocha.opts \"dist/**/*.spec.js\""
+  },
+  "standard": {
+    "ignore": [
+      "dist/**"
+    ],
+    "parser": "babel-eslint"
   }
 }

packages/xo-lib/session-error.js

@@ -1,9 +0,0 @@
-'use strict'
-
-// ===================================================================
-
-var makeError = require('make-error')
-
-// ===================================================================
-
-module.exports = makeError('SessionError')

packages/xo-lib/src/index.js

@@ -0,0 +1,71 @@
+import startsWith from 'lodash.startswith'
+import JsonRpcWebSocketClient, {
+  OPEN,
+  CLOSED
+} from 'jsonrpc-websocket-client'
+import { BaseError } from 'make-error'
+
+// ===================================================================
+
+const noop = () => {}
+
+// ===================================================================
+
+export class XoError extends BaseError {}
+
+// -------------------------------------------------------------------
+
+export default class Xo extends JsonRpcWebSocketClient {
+  constructor (opts) {
+    const url = opts && opts.url || '.'
+    super(`${url === '/' ? '' : url}/api/`)
+
+    this._credentials = opts && opts.credentials || null
+    this._user = null
+
+    this.on(OPEN, () => {
+      if (this._credentials) {
+        this._signIn(this._credentials).catch(noop)
+      }
+    })
+    this.on(CLOSED, () => {
+      this._user = null
+    })
+  }
+
+  get user () {
+    return this._user
+  }
+
+  call (method, args, i) {
+    if (startsWith(method, 'session.')) {
+      return Promise.reject(
+        new XoError('session.*() methods are disabled from this interface')
+      )
+    }
+
+    const promise = super.call(method, args)
+    promise.retry = (predicate) => promise.catch((error) => {
+      i = (i || 0) + 1
+      if (predicate(error, i)) {
+        return this.call(method, args, i)
+      }
+    })
+
+    return promise
+  }
+
+  signIn (credentials) {
+    // Register this credentials for future use.
+    this._credentials = credentials
+
+    return this._signIn(credentials)
+  }
+
+  _signIn (credentials) {
+    return super.call('session.signIn', credentials).then((user) => {
+      this._user = user
+      this.emit('authenticated')
+    })
+  }
+}

packages/xo-lib/src/index.spec.js

@@ -0,0 +1,17 @@
+/* eslint-env mocha */
+
+import expect from 'must'
+
+// ===================================================================
+
+import myLib from './'
+
+// ===================================================================
+
+describe.skip('myLib', () => {
+  it('does something', () => {
+    // TODO: some real tests.
+
+    expect(myLib).to.exists()
+  })
+})

packages/xo-lib/xo.js

@@ -1,282 +0,0 @@
-'use strict'
-
-// ===================================================================
-
-var Bluebird = require('bluebird')
-var Collection = require('xo-collection').default
-var forEach = require('lodash.foreach')
-var Index = require('xo-collection/index')
-var isString = require('lodash.isstring')
-var startsWith = require('lodash.startswith')
-var UniqueIndex = require('xo-collection/unique-index')
-
-var Api = require('./api')
-var BackOff = require('./back-off')
-var ConnectionError = require('./connection-error')
-var SessionError = require('./session-error')
-
-// ===================================================================
-
-// function bind (fn, thisArg) {
-//   if (!fn) {
-//     return fn
-//   }
-
-//   return function () {
-//     return fn.apply(thisArg, arguments)
-//   }
-// }
-
-function makeStandaloneDeferred () {
-  var resolve, reject
-
-  var promise = new Bluebird(function (resolve_, reject_) {
-    resolve = resolve_
-    reject = reject_
-  })
-  promise.resolve = resolve
-  promise.reject = reject
-
-  return promise
-}
-
-function noop () {}
-
-// var trace =
-//   bind(console.trace, console) ||
-//   bind(console.log, console) ||
-//   noop
-
-// -------------------------------------------------------------------
-
-var defineProperty = Object.defineProperty
-
-function getDeprecatedUUID () {
-  // trace('.UUID is deprecated, use .id instead')
-
-  return this.id
-}
-
-function defineDeprecatedUUID (object) {
-  defineProperty(object, 'UUID', {
-    get: getDeprecatedUUID
-  })
-}
-
-// var LINK_RE = /^(.*)\$link\$$/
-// function createAutoLinks (collection, object) {
-//   var all = collection.all
-
-//   forEach(object, function resolveObject (value, key, object) {
-//     var matches = key.match(LINK_RE)
-//     if (!matches) {
-//       return
-//     }
-
-//     defineProperty(object, matches[1], {
-//       get: function () {
-//         return all[value]
-//       }
-//     })
-//   })
-// }
-
-function setMultiple (collection, items) {
-  var messages = collection.indexes.messagesByObject
-
-  forEach(items, function (item, key) {
-    defineDeprecatedUUID(item)
-    // createAutoLinks(collection, item)
-
-    defineProperty(item, 'messages', {
-      get: function () {
-        return messages[key]
-      }
-    })
-
-    collection.set(key, item)
-  })
-}
-
-function unsetMultiple (collection, items) {
-  forEach(items, function (_, key) {
-    if (collection.has(key)) {
-      collection.remove(key)
-    }
-  })
-}
-
-// ===================================================================
-
-function Xo (opts) {
-  if (!opts) {
-    opts = {}
-  } else if (isString(opts)) {
-    opts = {
-      url: opts
-    }
-  }
-
-  // -----------------------------------------------------------------
-
-  var api = new Api(opts.url)
-
-  api.on('connected', function () {
-    this._backOff.reset()
-    this.status = 'connected'
-
-    this._tryToOpenSession()
-  }.bind(this))
-
-  api.on('disconnected', function () {
-    this._closeSession()
-    this._connect()
-  }.bind(this))
-
-  api.on('notification', function (notification) {
-    if (notification.method !== 'all') {
-      return
-    }
-
-    var method = notification.params.type === 'exit'
-      ? unsetMultiple
-      : setMultiple
-
-    method(this.objects, notification.params.items)
-  }.bind(this))
-
-  // -----------------------------------------------------------------
-
-  var objects = this.objects = new Collection()
-  objects.createIndex('ref', new UniqueIndex('ref'))
-  objects.createIndex('type', new Index('type'))
-  objects.createIndex('messagesByObject', new Index(function (obj) {
-    if (obj.type === 'message') {
-      return obj.$object
-    }
-  }))
-
-  this.status = 'disconnected'
-  this.user = null
-
-  this._api = api
-  this._backOff = new BackOff()
-  this._credentials = opts.creadentials
-  this._session = makeStandaloneDeferred()
-  this._signIn = null
-
-  // -----------------------------------------------------------------
-
-  this._connect()
-}
-
-Xo.prototype.call = function (method, params, retryOnConnectionError) {
-  // Prevent session.*() from being because it may interfere
-  // with this class session management.
-  if (startsWith(method, 'session.')) {
-    return Bluebird.reject(
-      new Error('session.*() methods are disabled from this interface')
-    )
-  }
-
-  var this_ = this
-  return this._session.then(function () {
-    return this_._api.call(method, params)
-  }).catch(function (error) {
-    if (
-      error instanceof SessionError ||
-      retryOnConnectionError && error instanceof ConnectionError
-    ) {
-      // Automatically requeue this call.
-      return this_.call(method, params)
-    }
-
-    throw error
-  })
-}
-
-Xo.prototype.signIn = function (credentials) {
-  this.signOut()
-
-  this._credentials = credentials
-  this._signIn = makeStandaloneDeferred()
-
-  this._tryToOpenSession()
-
-  return this._signIn
-}
-
-Xo.prototype.signOut = function () {
-  this._closeSession()
-  this._credentials = null
-
-  var signIn = this._signIn
-  if (signIn && signIn.isPending()) {
-    signIn.reject(new SessionError('sign in aborted'))
-  }
-
-  return this.status === 'connected'
-
-    // Attempt to sign out and ignore any return values and errors.
-    ? this._api.call('session.signOut').then(noop, noop)
-
-    // Always return a promise.
-    : Bluebird.resolve()
-}
-
-Xo.prototype._connect = function _connect () {
-  this.status = 'connecting'
-
-  return this._api.connect().bind(this).catch(function (error) {
-    console.warn('could not connect:', error)
-
-    return this._backOff.wait().bind(this).then(_connect)
-  })
-}
-
-Xo.prototype._closeSession = function () {
-  if (!this._session.isPending()) {
-    this._session = makeStandaloneDeferred()
-  }
-
-  this.user = null
-}
-
-Xo.prototype._tryToOpenSession = function () {
-  var credentials = this._credentials
-  if (!credentials || this.status !== 'connected') {
-    return
-  }
-
-  this._api.call('session.signIn', credentials).bind(this).then(
-    function (user) {
-      this.user = user
-
-      this._api.call('xo.getAllObjects').bind(this).then(function (objects) {
-        this.objects.clear()
-        setMultiple(this.objects, objects)
-      })
-
-      // Validate the sign in.
-      var signIn = this._signIn
-      if (signIn) {
-        signIn.resolve()
-      }
-
-      // Open the session.
-      this._session.resolve()
-    },
-
-    function (error) {
-      // Reject the sign in.
-      var signIn = this._signIn
-      if (signIn) {
-        signIn.reject(error)
-      }
-    }
-  )
-}
-
-// ===================================================================
-
-module.exports = Xo