Make the streaming API also handle websockets (because trying to get the browser EventSource interface to

work flawlessly was a nightmare). WARNING: This commit makes the web UI connect to the streaming API instead
of ActionCable like before. This means that if you are upgrading, you should set that up beforehand.

14 files changed, 307 insertions, 129 deletions

diff --git a/.env.production.sample b/.env.production.sample
index 1a96775de..ef0af9d5c 100644
--- a/.env.production.sample
+++ b/.env.production.sample
@@ -43,5 +43,5 @@ SMTP_FROM_ADDRESS=notifications@example.com
 # Optional alias for S3 if you want to use Cloudfront or Cloudflare in front
 # S3_CLOUDFRONT_HOST=
 
-# Optional Firebase Cloud Messaging API key
-FCM_API_KEY=
+# Streaming API integration
+# STREAMING_API_BASE_URL=
diff --git a/app/assets/javascripts/application.js b/app/assets/javascripts/application.js
index c442ded61..e2fffd932 100644
--- a/app/assets/javascripts/application.js
+++ b/app/assets/javascripts/application.js
@@ -13,4 +13,3 @@
 //= require jquery
 //= require jquery_ujs
 //= require components
-//= require cable
diff --git a/app/assets/javascripts/cable.js b/app/assets/javascripts/cable.js
deleted file mode 100644
index 03258761c..000000000
--- a/app/assets/javascripts/cable.js
+++ /dev/null
@@ -1,12 +0,0 @@
-// Action Cable provides the framework to deal with WebSockets in Rails.
-// You can generate new channels where WebSocket features live using the rails generate channel command.
-//
-//= require action_cable
-//= require_self
-
-(function() {
-  this.App || (this.App = {});
-
-  App.cable = ActionCable.createConsumer();
-
-}).call(this);
diff --git a/app/assets/javascripts/components/containers/mastodon.jsx b/app/assets/javascripts/components/containers/mastodon.jsx
index 5fd43fb2b..46a01b200 100644
--- a/app/assets/javascripts/components/containers/mastodon.jsx
+++ b/app/assets/javascripts/components/containers/mastodon.jsx
@@ -43,6 +43,7 @@ import hu from 'react-intl/locale-data/hu';
 import uk from 'react-intl/locale-data/uk';
 import getMessagesForLocale from '../locales';
 import { hydrateStore } from '../actions/store';
+import createStream from '../stream';
 
 const store = configureStore();
 
@@ -60,28 +61,27 @@ const Mastodon = React.createClass({
     locale: React.PropTypes.string.isRequired
   },
 
-  componentWillMount() {
-    const { locale } = this.props;
-
-    if (typeof App !== 'undefined') {
-      this.subscription = App.cable.subscriptions.create('TimelineChannel', {
-
-        received (data) {
-          switch(data.event) {
-          case 'update':
-            store.dispatch(updateTimeline('home', JSON.parse(data.payload)));
-            break;
-          case 'delete':
-            store.dispatch(deleteFromTimelines(data.payload));
-            break;
-          case 'notification':
-            store.dispatch(updateNotifications(JSON.parse(data.payload), getMessagesForLocale(locale), locale));
-            break;
-          }
+  componentDidMount() {
+    const { locale }  = this.props;
+    const accessToken = store.getState().getIn(['meta', 'access_token']);
+
+    this.subscription = createStream(accessToken, 'user', {
+
+      received (data) {
+        switch(data.event) {
+        case 'update':
+          store.dispatch(updateTimeline('home', JSON.parse(data.payload)));
+          break;
+        case 'delete':
+          store.dispatch(deleteFromTimelines(data.payload));
+          break;
+        case 'notification':
+          store.dispatch(updateNotifications(JSON.parse(data.payload), getMessagesForLocale(locale), locale));
+          break;
         }
+      }
 
-      });
-    }
+    });
 
     // Desktop notifications
     if (typeof window.Notification !== 'undefined' && Notification.permission === 'default') {
@@ -91,7 +91,8 @@ const Mastodon = React.createClass({
 
   componentWillUnmount () {
     if (typeof this.subscription !== 'undefined') {
-      this.subscription.unsubscribe();
+      this.subscription.close();
+      this.subscription = null;
     }
   },
 
diff --git a/app/assets/javascripts/components/features/hashtag_timeline/index.jsx b/app/assets/javascripts/components/features/hashtag_timeline/index.jsx
index 7548e6d56..4a0e7684d 100644
--- a/app/assets/javascripts/components/features/hashtag_timeline/index.jsx
+++ b/app/assets/javascripts/components/features/hashtag_timeline/index.jsx
@@ -8,45 +8,49 @@ import {
   deleteFromTimelines
 } from '../../actions/timelines';
 import ColumnBackButtonSlim from '../../components/column_back_button_slim';
+import createStream from '../../stream';
+
+const mapStateToProps = state => ({
+  accessToken: state.getIn(['meta', 'access_token'])
+});
 
 const HashtagTimeline = React.createClass({
 
   propTypes: {
     params: React.PropTypes.object.isRequired,
-    dispatch: React.PropTypes.func.isRequired
+    dispatch: React.PropTypes.func.isRequired,
+    accessToken: React.PropTypes.string.isRequired
   },
 
   mixins: [PureRenderMixin],
 
   _subscribe (dispatch, id) {
-    if (typeof App !== 'undefined') {
-      this.subscription = App.cable.subscriptions.create({
-        channel: 'HashtagChannel',
-        tag: id
-      }, {
-
-        received (data) {
-          switch(data.event) {
-          case 'update':
-            dispatch(updateTimeline('tag', JSON.parse(data.payload)));
-            break;
-          case 'delete':
-            dispatch(deleteFromTimelines(data.payload));
-            break;
-          }
+    const { accessToken } = this.props;
+
+    this.subscription = createStream(accessToken, `hashtag&tag=${id}`, {
+
+      received (data) {
+        switch(data.event) {
+        case 'update':
+          dispatch(updateTimeline('tag', JSON.parse(data.payload)));
+          break;
+        case 'delete':
+          dispatch(deleteFromTimelines(data.payload));
+          break;
         }
+      }
 
-      });
-    }
+    });
   },
 
   _unsubscribe () {
     if (typeof this.subscription !== 'undefined') {
-      this.subscription.unsubscribe();
+      this.subscription.close();
+      this.subscription = null;
     }
   },
 
-  componentWillMount () {
+  componentDidMount () {
     const { dispatch } = this.props;
     const { id } = this.props.params;
 
@@ -79,4 +83,4 @@ const HashtagTimeline = React.createClass({
 
 });
 
-export default connect()(HashtagTimeline);
+export default connect(mapStateToProps)(HashtagTimeline);
diff --git a/app/assets/javascripts/components/features/public_timeline/index.jsx b/app/assets/javascripts/components/features/public_timeline/index.jsx
index 42970061c..36d68dbbb 100644
--- a/app/assets/javascripts/components/features/public_timeline/index.jsx
+++ b/app/assets/javascripts/components/features/public_timeline/index.jsx
@@ -9,46 +9,51 @@ import {
 } from '../../actions/timelines';
 import { defineMessages, injectIntl } from 'react-intl';
 import ColumnBackButtonSlim from '../../components/column_back_button_slim';
+import createStream from '../../stream';
 
 const messages = defineMessages({
   title: { id: 'column.public', defaultMessage: 'Public' }
 });
 
+const mapStateToProps = state => ({
+  accessToken: state.getIn(['meta', 'access_token'])
+});
+
 const PublicTimeline = React.createClass({
 
   propTypes: {
     dispatch: React.PropTypes.func.isRequired,
-    intl: React.PropTypes.object.isRequired
+    intl: React.PropTypes.object.isRequired,
+    accessToken: React.PropTypes.string.isRequired
   },
 
   mixins: [PureRenderMixin],
 
-  componentWillMount () {
-    const { dispatch } = this.props;
+  componentDidMount () {
+    const { dispatch, accessToken } = this.props;
 
     dispatch(refreshTimeline('public'));
 
-    if (typeof App !== 'undefined') {
-      this.subscription = App.cable.subscriptions.create('PublicChannel', {
+    this.subscription = createStream(accessToken, 'public', {
 
-        received (data) {
-          switch(data.event) {
-          case 'update':
-            dispatch(updateTimeline('public', JSON.parse(data.payload)));
-            break;
-          case 'delete':
-            dispatch(deleteFromTimelines(data.payload));
-            break;
-          }
+      received (data) {
+        switch(data.event) {
+        case 'update':
+          dispatch(updateTimeline('public', JSON.parse(data.payload)));
+          break;
+        case 'delete':
+          dispatch(deleteFromTimelines(data.payload));
+          break;
         }
+      }
 
-      });
-    }
+    });
   },
 
   componentWillUnmount () {
     if (typeof this.subscription !== 'undefined') {
-      this.subscription.unsubscribe();
+      this.subscription.close();
+      this.subscription = null;
     }
   },
 
@@ -65,4 +70,4 @@ const PublicTimeline = React.createClass({
 
 });
 
-export default connect()(injectIntl(PublicTimeline));
+export default connect(mapStateToProps)(injectIntl(PublicTimeline));
diff --git a/app/assets/javascripts/components/stream.jsx b/app/assets/javascripts/components/stream.jsx
new file mode 100644
index 000000000..0787399f6
--- /dev/null
+++ b/app/assets/javascripts/components/stream.jsx
@@ -0,0 +1,21 @@
+import WebSocketClient from 'websocket.js';
+
+const createWebSocketURL = (url) => {
+  const a = document.createElement('a');
+
+  a.href     = url;
+  a.href     = a.href;
+  a.protocol = a.protocol.replace('http', 'ws');
+
+  return a.href;
+};
+
+export default function getStream(accessToken, stream, { connected, received, disconnected }) {
+  const ws = new WebSocketClient(`${createWebSocketURL(STREAMING_API_BASE_URL)}/api/v1/streaming/?access_token=${accessToken}&stream=${stream}`);
+
+  ws.onopen    = connected;
+  ws.onmessage = e => received(JSON.parse(e.data));
+  ws.onclose   = disconnected;
+
+  return ws;
+};
diff --git a/app/views/home/index.html.haml b/app/views/home/index.html.haml
index 0147f4064..9e3b94463 100644
--- a/app/views/home/index.html.haml
+++ b/app/views/home/index.html.haml
@@ -1,5 +1,6 @@
 - content_for :header_tags do
   :javascript
+    window.STREAMING_API_BASE_URL = '#{Rails.configuration.x.streaming_api_base_url}';
     window.INITIAL_STATE = #{json_escape(render(file: 'home/initial_state', formats: :json))}
 
   = javascript_include_tag 'application'
diff --git a/config/initializers/ostatus.rb b/config/initializers/ostatus.rb
index faa9940b0..fb0b8b7fe 100644
--- a/config/initializers/ostatus.rb
+++ b/config/initializers/ostatus.rb
@@ -10,8 +10,10 @@ Rails.application.configure do
   config.x.use_s3       = ENV['S3_ENABLED'] == 'true'
 
   config.action_mailer.default_url_options = { host: host, protocol: https ? 'https://' : 'http://', trailing_slash: false }
+  config.x.streaming_api_base_url          = 'http://localhost:4000'
 
   if Rails.env.production?
     config.action_cable.allowed_request_origins = ["http#{https ? 's' : ''}://#{host}"]
+    config.x.streaming_api_base_url             = ENV.fetch('STREAMING_API_BASE_URL') { "http#{https ? 's' : ''}://#{host}" }
   end
 end
diff --git a/docker-compose.yml b/docker-compose.yml
index e1f1f1c4c..e6002eaa5 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -19,6 +19,16 @@ services:
     volumes:
       - ./public/assets:/mastodon/public/assets
       - ./public/system:/mastodon/public/system
+  streaming:
+    restart: always
+    build: .
+    env_file: .env.production
+    command: npm run start
+    ports:
+      - "4000:4000"
+    depends_on:
+      - db
+      - redis
   sidekiq:
     restart: always
     build: .
diff --git a/docs/Running-Mastodon/Production-guide.md b/docs/Running-Mastodon/Production-guide.md
index 76964d995..ff4427dd2 100644
--- a/docs/Running-Mastodon/Production-guide.md
+++ b/docs/Running-Mastodon/Production-guide.md
@@ -49,6 +49,22 @@ server {
     tcp_nodelay on;
   }
 
+  location /api/v1/streaming {
+    proxy_set_header Host $host;
+    proxy_set_header X-Real-IP $remote_addr;
+    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
+    proxy_set_header X-Forwarded-Proto https;
+
+    proxy_pass http://localhost:4000;
+    proxy_buffering off;
+    proxy_redirect off;
+    proxy_http_version 1.1;
+    proxy_set_header Upgrade $http_upgrade;
+    proxy_set_header Connection $connection_upgrade;
+
+    tcp_nodelay on;
+  }
+
   error_page 500 501 502 503 504 /500.html;
 }
 ```
@@ -162,6 +178,27 @@ Restart=always
 WantedBy=multi-user.target
 ```
 
+Example systemd configuration file for the streaming API, to be placed in `/etc/systemd/system/mastodon-streaming.service`:
+
+```systemd
+[Unit]
+Description=mastodon-streaming
+After=network.target
+
+[Service]
+Type=simple
+User=mastodon
+WorkingDirectory=/home/mastodon/live
+Environment="NODE_ENV=production"
+Environment="PORT=4000"
+ExecStart=/usr/bin/npm run start
+TimeoutSec=15
+Restart=always
+
+[Install]
+WantedBy=multi-user.target
+```
+
 This allows you to `sudo systemctl enable mastodon-*.service` and `sudo systemctl start mastodon-*.service` to get things going.
 
 ## Cronjobs
diff --git a/package.json b/package.json
index 9685f07a4..def42f596 100644
--- a/package.json
+++ b/package.json
@@ -18,6 +18,7 @@
     "babelify": "^7.3.0",
     "browserify": "^13.1.0",
     "browserify-incremental": "^3.1.1",
+    "bufferutil": "^2.0.0",
     "chai": "^3.5.0",
     "chai-enzyme": "^0.5.2",
     "css-loader": "^0.26.1",
@@ -64,6 +65,9 @@
     "sass-loader": "^4.0.2",
     "sinon": "^1.17.6",
     "style-loader": "^0.13.1",
-    "webpack": "^1.14.0"
+    "utf-8-validate": "^3.0.0",
+    "webpack": "^1.14.0",
+    "websocket.js": "^0.1.7",
+    "ws": "^2.0.2"
   }
 }
diff --git a/streaming/index.js b/streaming/index.js
index e5a2778f8..16dda5c1e 100644
--- a/streaming/index.js
+++ b/streaming/index.js
@@ -1,8 +1,11 @@
 import dotenv from 'dotenv'
 import express from 'express'
+import http from 'http'
 import redis from 'redis'
 import pg from 'pg'
 import log from 'npmlog'
+import url from 'url'
+import WebSocket from 'ws'
 
 const env = process.env.NODE_ENV || 'development'
 
@@ -27,8 +30,10 @@ const pgConfigs = {
   }
 }
 
-const app = express()
+const app    = express()
 const pgPool = new pg.Pool(pgConfigs[env])
+const server = http.createServer(app)
+const wss    = new WebSocket.Server({ server })
 
 const allowCrossDomain = (req, res, next) => {
   res.header('Access-Control-Allow-Origin', '*')
@@ -38,22 +43,7 @@ const allowCrossDomain = (req, res, next) => {
   next()
 }
 
-const authenticationMiddleware = (req, res, next) => {
-  if (req.method === 'OPTIONS') {
-    return next()
-  }
-
-  const authorization = req.get('Authorization')
-
-  if (!authorization) {
-    const err = new Error('Missing access token')
-    err.statusCode = 401
-
-    return next(err)
-  }
-
-  const token = authorization.replace(/^Bearer /, '')
-
+const accountFromToken = (token, req, next) => {
   pgPool.connect((err, client, done) => {
     if (err) {
       return next(err)
@@ -80,26 +70,36 @@ const authenticationMiddleware = (req, res, next) => {
   })
 }
 
+const authenticationMiddleware = (req, res, next) => {
+  if (req.method === 'OPTIONS') {
+    return next()
+  }
+
+  const authorization = req.get('Authorization')
+
+  if (!authorization) {
+    const err = new Error('Missing access token')
+    err.statusCode = 401
+
+    return next(err)
+  }
+
+  const token = authorization.replace(/^Bearer /, '')
+
+  accountFromToken(token, req, next)
+}
+
 const errorMiddleware = (err, req, res, next) => {
   log.error(err)
   res.writeHead(err.statusCode || 500, { 'Content-Type': 'application/json' })
-  res.end(JSON.stringify({ error: err.statusCode ? `${err}` : 'An unexpected error occured' }))
+  res.end(JSON.stringify({ error: err.statusCode ? `${err}` : 'An unexpected error occurred' }))
 }
 
 const placeholders = (arr, shift = 0) => arr.map((_, i) => `$${i + 1 + shift}`).join(', ');
 
-const streamFrom = (id, req, res, needsFiltering = false) => {
+const streamFrom = (redisClient, id, req, output, needsFiltering = false) => {
   log.verbose(`Starting stream from ${id} for ${req.accountId}`)
 
-  res.setHeader('Content-Type', 'text/event-stream')
-  res.setHeader('Transfer-Encoding', 'chunked')
-
-  const redisClient = redis.createClient({
-    host:     process.env.REDIS_HOST     || '127.0.0.1',
-    port:     process.env.REDIS_PORT     || 6379,
-    password: process.env.REDIS_PASSWORD
-  })
-
   redisClient.on('message', (channel, message) => {
     const { event, payload } = JSON.parse(message)
 
@@ -127,36 +127,107 @@ const streamFrom = (id, req, res, needsFiltering = false) => {
             return
           }
 
-          res.write(`event: ${event}\n`)
-          res.write(`data: ${payload}\n\n`)
+          log.silly(`Transmitting for ${req.accountId}: ${event} ${payload}`)
+          output(event, payload)
         })
       })
     } else {
-      res.write(`event: ${event}\n`)
-      res.write(`data: ${payload}\n\n`)
+      log.silly(`Transmitting for ${req.accountId}: ${event} ${payload}`)
+      output(event, payload)
     }
   })
 
+  redisClient.subscribe(id)
+}
+
+// Setup stream output to HTTP
+const streamToHttp = (req, res, redisClient) => {
+  res.setHeader('Content-Type', 'text/event-stream')
+  res.setHeader('Transfer-Encoding', 'chunked')
+
   const heartbeat = setInterval(() => res.write(':thump\n'), 15000)
 
   req.on('close', () => {
-    log.verbose(`Ending stream from ${id} for ${req.accountId}`)
+    log.verbose(`Ending stream for ${req.accountId}`)
     clearInterval(heartbeat)
     redisClient.quit()
   })
 
-  redisClient.subscribe(id)
+  return (event, payload) => {
+    res.write(`event: ${event}\n`)
+    res.write(`data: ${payload}\n\n`)
+  }
+}
+
+// Setup stream output to WebSockets
+const streamToWs = (req, ws, redisClient) => {
+  ws.on('close', () => {
+    log.verbose(`Ending stream for ${req.accountId}`)
+    redisClient.quit()
+  })
+
+  return (event, payload) => {
+    ws.send(JSON.stringify({ event, payload }))
+  }
 }
 
+// Get new redis connection
+const getRedisClient = () => redis.createClient({
+  host:     process.env.REDIS_HOST     || '127.0.0.1',
+  port:     process.env.REDIS_PORT     || 6379,
+  password: process.env.REDIS_PASSWORD
+})
+
 app.use(allowCrossDomain)
 app.use(authenticationMiddleware)
 app.use(errorMiddleware)
 
-app.get('/api/v1/streaming/user',    (req, res) => streamFrom(`timeline:${req.accountId}`, req, res))
-app.get('/api/v1/streaming/public',  (req, res) => streamFrom('timeline:public', req, res, true))
-app.get('/api/v1/streaming/hashtag', (req, res) => streamFrom(`timeline:hashtag:${req.params.tag}`, req, res, true))
+app.get('/api/v1/streaming/user', (req, res) => {
+  const redisClient = getRedisClient()
+  streamFrom(redisClient, `timeline:${req.accountId}`, req, streamToHttp(req, res, redisClient))
+})
+
+app.get('/api/v1/streaming/public', (req, res) => {
+  const redisClient = getRedisClient()
+  streamFrom(redisClient, 'timeline:public', req, streamToHttp(req, res, redisClient), true)
+})
+
+app.get('/api/v1/streaming/hashtag', (req, res) => {
+  const redisClient = getRedisClient()
+  streamFrom(redisClient, `timeline:hashtag:${req.params.tag}`, req, streamToHttp(req, res, redisClient), true)
+})
 
-log.level = 'verbose'
-log.info(`Starting HTTP server on port ${process.env.PORT || 4000}`)
+wss.on('connection', ws => {
+  const location = url.parse(ws.upgradeReq.url, true)
+  const token    = location.query.access_token
+  const req      = {}
 
-app.listen(process.env.PORT || 4000)
+  accountFromToken(token, req, err => {
+    if (err) {
+      log.error(err)
+      ws.close()
+      return
+    }
+
+    const redisClient = getRedisClient()
+
+    switch(location.query.stream) {
+    case 'user':
+      streamFrom(redisClient, `timeline:${req.accountId}`, req, streamToWs(req, ws, redisClient))
+      break;
+    case 'public':
+      streamFrom(redisClient, 'timeline:public', req, streamToWs(req, ws, redisClient), true)
+      break;
+    case 'hashtag':
+      streamFrom(redisClient, `timeline:hashtag:${location.query.tag}`, req, streamToWs(req, ws, redisClient), true)
+      break;
+    default:
+      ws.close()
+    }
+  })
+})
+
+server.listen(process.env.PORT || 4000, () => {
+  log.level = process.env.LOG_LEVEL || 'verbose'
+  log.info(`Starting streaming API server on port ${server.address().port}`)
+})
diff --git a/yarn.lock b/yarn.lock
index bd1747929..8038411fe 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -1237,6 +1237,12 @@ babylon@^6.15.0:
   version "6.15.0"
   resolved "https://registry.yarnpkg.com/babylon/-/babylon-6.15.0.tgz#ba65cfa1a80e1759b0e89fb562e27dccae70348e"
 
+backoff@^2.4.1:
+  version "2.5.0"
+  resolved "https://registry.yarnpkg.com/backoff/-/backoff-2.5.0.tgz#f616eda9d3e4b66b8ca7fca79f695722c5f8e26f"
+  dependencies:
+    precond "0.2"
+
 balanced-match@^0.4.1, balanced-match@^0.4.2:
   version "0.4.2"
   resolved "https://registry.yarnpkg.com/balanced-match/-/balanced-match-0.4.2.tgz#cb3f3e3c732dc0f01ee70b403f302e61d7709838"
@@ -1263,6 +1269,10 @@ binary-extensions@^1.0.0:
   version "1.7.0"
   resolved "https://registry.yarnpkg.com/binary-extensions/-/binary-extensions-1.7.0.tgz#6c1610db163abfb34edfe42fa423343a1e01185d"
 
+bindings@~1.2.1:
+  version "1.2.1"
+  resolved "https://registry.yarnpkg.com/bindings/-/bindings-1.2.1.tgz#14ad6113812d2d37d72e67b4cacb4bb726505f11"
+
 bl@~1.1.2:
   version "1.1.2"
   resolved "https://registry.yarnpkg.com/bl/-/bl-1.1.2.tgz#fdca871a99713aa00d19e3bbba41c44787a65398"
@@ -1479,6 +1489,13 @@ buffer@^4.1.0, buffer@^4.9.0:
     ieee754 "^1.1.4"
     isarray "^1.0.0"
 
+bufferutil@^2.0.0:
+  version "2.0.0"
+  resolved "https://registry.yarnpkg.com/bufferutil/-/bufferutil-2.0.0.tgz#6588ed4bafa300798b26dc048494a51abde83507"
+  dependencies:
+    bindings "~1.2.1"
+    nan "~2.5.0"
+
 builtin-modules@^1.0.0:
   version "1.1.1"
   resolved "https://registry.yarnpkg.com/builtin-modules/-/builtin-modules-1.1.1.tgz#270f076c5a72c02f5b65a47df94c5fe3a278892f"
@@ -3664,9 +3681,9 @@ ms@0.7.2:
   version "0.7.2"
   resolved "https://registry.yarnpkg.com/ms/-/ms-0.7.2.tgz#ae25cf2512b3885a1d95d7f037868d8431124765"
 
-nan@^2.3.0, nan@^2.3.2:
-  version "2.4.0"
-  resolved "https://registry.yarnpkg.com/nan/-/nan-2.4.0.tgz#fb3c59d45fe4effe215f0b890f8adf6eb32d2232"
+nan@^2.3.0, nan@^2.3.2, nan@~2.5.0:
+  version "2.5.1"
+  resolved "https://registry.yarnpkg.com/nan/-/nan-2.5.1.tgz#d5b01691253326a97a2bbee9e61c55d8d60351e2"
 
 negotiator@0.6.1:
   version "0.6.1"
@@ -3808,16 +3825,7 @@ normalize-url@^1.4.0:
     gauge "~2.6.0"
     set-blocking "~2.0.0"
 
-npmlog@4.x, npmlog@^4.0.0:
-  version "4.0.0"
-  resolved "https://registry.yarnpkg.com/npmlog/-/npmlog-4.0.0.tgz#e094503961c70c1774eb76692080e8d578a9f88f"
-  dependencies:
-    are-we-there-yet "~1.1.2"
-    console-control-strings "~1.1.0"
-    gauge "~2.6.0"
-    set-blocking "~2.0.0"
-
-npmlog@^4.0.2:
+npmlog@4.x, npmlog@^4.0.0, npmlog@^4.0.2:
   version "4.0.2"
   resolved "https://registry.yarnpkg.com/npmlog/-/npmlog-4.0.2.tgz#d03950e0e78ce1527ba26d2a7592e9348ac3e75f"
   dependencies:
@@ -4401,6 +4409,10 @@ postgres-interval@~1.0.0:
   dependencies:
     xtend "^4.0.0"
 
+precond@0.2:
+  version "0.2.3"
+  resolved "https://registry.yarnpkg.com/precond/-/precond-0.2.3.tgz#aa9591bcaa24923f1e0f4849d240f47efc1075ac"
+
 prelude-ls@~1.1.2:
   version "1.1.2"
   resolved "https://registry.yarnpkg.com/prelude-ls/-/prelude-ls-1.1.2.tgz#21932a549f5e52ffd9a827f570e04be62a97da54"
@@ -5556,6 +5568,10 @@ uid-number@~0.0.6:
   version "0.0.6"
   resolved "https://registry.yarnpkg.com/uid-number/-/uid-number-0.0.6.tgz#0ea10e8035e8eb5b8e4449f06da1c730663baa81"
 
+ultron@~1.1.0:
+  version "1.1.0"
+  resolved "https://registry.yarnpkg.com/ultron/-/ultron-1.1.0.tgz#b07a2e6a541a815fc6a34ccd4533baec307ca864"
+
 umd@^3.0.0:
   version "3.0.1"
   resolved "https://registry.yarnpkg.com/umd/-/umd-3.0.1.tgz#8ae556e11011f63c2596708a8837259f01b3d60e"
@@ -5603,6 +5619,13 @@ user-home@^1.1.1:
   version "1.1.1"
   resolved "https://registry.yarnpkg.com/user-home/-/user-home-1.1.1.tgz#2b5be23a32b63a7c9deb8d0f28d485724a3df190"
 
+utf-8-validate@^3.0.0:
+  version "3.0.0"
+  resolved "https://registry.yarnpkg.com/utf-8-validate/-/utf-8-validate-3.0.0.tgz#42e54dfbc7cdfbd1d3bbf0a2f5000b4c6aeaa0c9"
+  dependencies:
+    bindings "~1.2.1"
+    nan "~2.5.0"
+
 util-deprecate@~1.0.1:
   version "1.0.2"
   resolved "https://registry.yarnpkg.com/util-deprecate/-/util-deprecate-1.0.2.tgz#450d4dc9fa70de732762fbd2d4a28981419a0ccf"
@@ -5727,6 +5750,12 @@ webpack@^1.13.1, webpack@^1.14.0:
     watchpack "^0.2.1"
     webpack-core "~0.6.9"
 
+websocket.js@^0.1.7:
+  version "0.1.7"
+  resolved "https://registry.yarnpkg.com/websocket.js/-/websocket.js-0.1.7.tgz#8d24cefb1a080c259e7e4740c02cab8f142df2b0"
+  dependencies:
+    backoff "^2.4.1"
+
 whatwg-fetch@>=0.10.0:
   version "1.0.0"
   resolved "https://registry.yarnpkg.com/whatwg-fetch/-/whatwg-fetch-1.0.0.tgz#01c2ac4df40e236aaa18480e3be74bd5c8eb798e"
@@ -5803,6 +5832,12 @@ write-file-atomic@^1.1.2:
     imurmurhash "^0.1.4"
     slide "^1.1.5"
 
+ws@^2.0.2:
+  version "2.0.2"
+  resolved "https://registry.yarnpkg.com/ws/-/ws-2.0.2.tgz#6257d1a679f0cb23658cba3dcad1316e2b1000c5"
+  dependencies:
+    ultron "~1.1.0"
+
 xdg-basedir@^2.0.0:
   version "2.0.0"
   resolved "https://registry.yarnpkg.com/xdg-basedir/-/xdg-basedir-2.0.0.tgz#edbc903cc385fc04523d966a335504b5504d1bd2"