Use the Twilio STUN/TURN service.

lib/ice.js

@@ -0,0 +1,34 @@
+var twilio = require('twilio')
+var winston = require('winston')
+
+if (process.env.TWILIO_SID && process.env.TWILIO_TOKEN) {
+  var client = twilio(process.env.TWILIO_SID, process.env.TWILIO_TOKEN)
+} else {
+  var client = null
+}
+
+var CACHE_LIFETIME = 5 * 60 * 1000 // 5 minutes
+var cachedPromise = null
+
+function clearCache() {
+  cachedPromise = null
+}
+
+exports.getICEServers = function () {
+  if (client == null) return Promise.resolve({})
+  if (cachedPromise) return cachedPromise
+
+  cachedPromise = new Promise(function (resolve, reject) {
+    client.tokens.create({}, function(err, token) {
+      if (err) {
+        winston.error(err.message)
+        return resolve({})
+      }
+
+      setTimeout(clearCache, CACHE_LIFETIME)
+      resolve(token.ice_servers)
+    })
+  })
+
+  return cachedPromise
+}

lib/server.js

@@ -1,11 +1,12 @@
 var db = require('./db')
 var express = require('express')
+var expressWinston = require('express-winston')
 var fs = require('fs')
 var http = require('http')
+var ice = require('./ice')
 var path = require('path')
 var socketIO = require('socket.io')
 var winston = require('winston')
-var expressWinston = require('express-winston')
 
 var app = express()
 var server = http.Server(app)
@@ -62,6 +63,12 @@ io.on('connection', function (socket) {
     })
   })
 
+  socket.on('rtcConfig', function (_, res) {
+    ice.getICEServers().then(function (iceServers) {
+      res({ iceServers: iceServers })
+    })
+  })
+
   socket.on('disconnect', function () {
     db.remove(upload)
   })

lib/stores/DownloadStore.js

@@ -1,7 +1,7 @@
 import DownloadActions from '../actions/DownloadActions'
-import webtorrent from '../webtorrent'
 import alt from '../alt'
 import socket from 'filepizza-socket'
+import { getClient } from '../wt'
 
 const SPEED_REFRESH_TIME = 2000
 
@@ -34,36 +34,38 @@ export default alt.createStore(class DownloadStore {
     if (this.status !== 'ready') return
     this.status = 'requesting'
 
-    webtorrent.download(this.infoHash, (torrent) => {
-      this.setState({ status: 'downloading' })
+    getClient().then((client) => {
+      client.download(this.infoHash, (torrent) => {
+        this.setState({ status: 'downloading' })
 
-      const updateSpeed = () => {
-        this.setState({
-          speedUp: torrent.swarm.uploadSpeed(),
-          speedDown: torrent.swarm.downloadSpeed(),
-          peers: torrent.swarm.wires.length
-        })
-      }
+        const updateSpeed = () => {
+          this.setState({
+            speedUp: torrent.swarm.uploadSpeed(),
+            speedDown: torrent.swarm.downloadSpeed(),
+            peers: torrent.swarm.wires.length
+          })
+        }
 
-      torrent.on('upload', updateSpeed)
-      torrent.on('download', updateSpeed)
-      setInterval(updateSpeed, SPEED_REFRESH_TIME)
+        torrent.on('upload', updateSpeed)
+        torrent.on('download', updateSpeed)
+        setInterval(updateSpeed, SPEED_REFRESH_TIME)
 
-      const file = torrent.files[0]
-      const stream = file.createReadStream()
-      stream.on('data', (chunk) => {
-        if (this.status !== 'downloading') return
+        const file = torrent.files[0]
+        const stream = file.createReadStream()
+        stream.on('data', (chunk) => {
+          if (this.status !== 'downloading') return
 
-        if (torrent.progress === 1) {
-          this.setState({ status: 'done', progress: 1 })
-          file.getBlobURL((err, blobURL) => {
-            if (err) throw err
-            downloadBlobURL(this.fileName, blobURL)
-          })
-        } else {
-          this.setState({ progress: torrent.progress })
-        }
+          if (torrent.progress === 1) {
+            this.setState({ status: 'done', progress: 1 })
+            file.getBlobURL((err, blobURL) => {
+              if (err) throw err
+              downloadBlobURL(this.fileName, blobURL)
+            })
+          } else {
+            this.setState({ progress: torrent.progress })
+          }
 
+        })
       })
     })
   }

lib/stores/UploadStore.js

@@ -1,7 +1,7 @@
 import UploadActions from '../actions/UploadActions'
 import alt from '../alt'
 import socket from 'filepizza-socket'
-import webtorrent from '../webtorrent'
+import { getClient } from '../wt'
 
 const SPEED_REFRESH_TIME = 2000
 
@@ -24,35 +24,37 @@ export default alt.createStore(class UploadStore {
     if (this.status !== 'ready') return
     this.status = 'processing'
 
-    webtorrent.seed(file, (torrent) => {
+    getClient().then((client) => {
+      client.seed(file, (torrent) => {
 
-      const updateSpeed = () => {
-        this.setState({
-          speedUp: torrent.swarm.uploadSpeed(),
-          peers: torrent.swarm.wires.length
-        })
-      }
-
-      torrent.on('upload', updateSpeed)
-      torrent.on('download', updateSpeed)
-      setInterval(updateSpeed, SPEED_REFRESH_TIME)
-
-      socket.emit('upload', {
-        fileName: file.name,
-        fileSize: file.size,
-        fileType: file.type,
-        infoHash: torrent.infoHash
-      }, (token) => {
-        this.setState({
-          status: 'uploading',
-          token: token,
+        const updateSpeed = () => {
+          this.setState({
+            speedUp: torrent.swarm.uploadSpeed(),
+            peers: torrent.swarm.wires.length
+          })
+        }
+
+        torrent.on('upload', updateSpeed)
+        torrent.on('download', updateSpeed)
+        setInterval(updateSpeed, SPEED_REFRESH_TIME)
+
+        socket.emit('upload', {
           fileName: file.name,
           fileSize: file.size,
           fileType: file.type,
           infoHash: torrent.infoHash
+        }, (token) => {
+          this.setState({
+            status: 'uploading',
+            token: token,
+            fileName: file.name,
+            fileSize: file.size,
+            fileType: file.type,
+            infoHash: torrent.infoHash
+          })
         })
-      })
 
+      })
     })
   }
 

lib/webtorrent.js

@@ -1,3 +0,0 @@
-import WebTorrent from 'webtorrent'
-
-export default new WebTorrent({})

lib/wt.js

@@ -0,0 +1,11 @@
+import WebTorrent from 'webtorrent'
+import socket from 'filepizza-socket'
+
+export function getClient() {
+  return new Promise((resolve, reject) => {
+    socket.emit('rtcConfig', {}, (rtcConfig) => {
+      const client = new WebTorrent({ rtcConfig: rtcConfig })
+      resolve(client)
+    })
+  })
+}

package.json

@@ -36,6 +36,7 @@
     "socket.io": "^1.3.5",
     "socket.io-client": "^1.3.5",
     "stylus": "^0.50.0",
+    "twilio": "^2.3.0",
     "webrtcsupport": "^2.1.2",
     "webtorrent": "^0.56.0",
     "winston": "^1.0.1",