onHttpRequest() as part of the public API

client.js

@@ -36,7 +36,7 @@ function Client (peerId, port, torrent, opts) {
   // required
   self._peerId = Buffer.isBuffer(peerId)
     ? peerId
-    : new Buffer(peerId, 'utf8')
+    : new Buffer(peerId, 'hex')
   self._port = port
   self._infoHash = Buffer.isBuffer(torrent.infoHash)
     ? torrent.infoHash

examples/express-embed/package.json

@@ -0,0 +1,13 @@
+{
+  "name": "bittorrent-tracker-example-express-embed",
+  "version": "0.0.0",
+  "description": "Example for embedding bittorrent-tracker server in express.js",
+  "scripts": {
+    "server": "./server.js"
+  },
+  "author": "Astro <[email protected]>",
+  "license": "MIT",
+  "dependencies": {
+    "express": "^4.10.5"
+  }
+}

examples/express-embed/server.js

@@ -0,0 +1,16 @@
+#!/usr/bin/env node
+
+var Server = require('../..').Server
+var express = require('express')
+var app = express()
+
+var server = new Server({
+  http: false, // we do our own
+  udp: false   // not interested
+})
+
+var onHttpRequest = server.onHttpRequest.bind(server)
+app.get('/announce', onHttpRequest)
+app.get('/scrape', onHttpRequest)
+
+app.listen(8080)

lib/common.js

@@ -15,7 +15,7 @@ exports.EVENT_IDS = {
   1: 'completed',
   2: 'started',
   3: 'stopped'
-};
+}
 
 function toUInt32 (n) {
   var buf = new Buffer(4)
@@ -24,8 +24,12 @@ function toUInt32 (n) {
 }
 exports.toUInt32 = toUInt32
 
-exports.binaryToUtf8 = function (str) {
-  return new Buffer(str, 'binary').toString('utf8')
+exports.binaryToHex = function (str) {
+  return new Buffer(str, 'binary').toString('hex')
+}
+
+exports.hexToBinary = function (str) {
+  return new Buffer(str, 'hex').toString('binary')
 }
 
 /**

lib/parse_http.js

@@ -11,48 +11,44 @@ function parseHttpRequest (req, options) {
   if (s[0] === '/announce') {
     params.action = common.ACTIONS.ANNOUNCE
 
-    params.peer_id = typeof params.peer_id === 'string' && common.binaryToUtf8(params.peer_id)
-    params.port = Number(params.port)
+    if (typeof params.info_hash !== 'string' || params.info_hash.length !== 20)
+      throw new Error('invalid info_hash')
+    params.info_hash = common.binaryToHex(params.info_hash)
+    if (typeof params.peer_id !== 'string' || params.peer_id.length !== 20)
+      throw new Error('invalid peer_id')
+    params.peer_id = common.binaryToHex(params.peer_id)
 
-    if (typeof params.info_hash !== 'string') throw new Error('invalid info_hash')
-    if (params.info_hash.length !== 20) throw new Error('invalid info_hash length')
-    if (typeof params.peer_id !== 'string') throw new Error('invalid peer_id')
-    if (params.peer_id.length !== 20) throw new Error('invalid peer_id length')
+    params.port = Number(params.port)
     if (!params.port) throw new Error('invalid port')
 
     params.left = Number(params.left)
     params.compact = Number(params.compact)
+    params.numwant = Math.min(
+      Number(params.numwant) || common.NUM_ANNOUNCE_PEERS,
+      common.MAX_ANNOUNCE_PEERS
+    )
 
     params.ip = options.trustProxy
       ? req.headers['x-forwarded-for'] || req.connection.remoteAddress
       : req.connection.remoteAddress.replace(REMOVE_IPV6_RE, '') // force ipv4
     params.addr = params.ip + ':' + params.port // TODO: ipv6 brackets?
 
-    params.numwant = Math.min(
-      Number(params.numwant) || common.NUM_ANNOUNCE_PEERS,
-      common.MAX_ANNOUNCE_PEERS
-    )
-
-    return params
   } else if (s[0] === '/scrape') { // unofficial scrape message
     params.action = common.ACTIONS.SCRAPE
-
-    if (typeof params.info_hash === 'string') {
+    if (typeof params.info_hash === 'string')
       params.info_hash = [ params.info_hash ]
-    }
-
-    if (params.info_hash) {
-      if (!Array.isArray(params.info_hash)) throw new Error('invalid info_hash array')
 
-      params.info_hash.forEach(function (infoHash) {
-        if (infoHash.length !== 20) {
+    if (Array.isArray(params.info_hash)) {
+      params.info_hash = params.info_hash.map(function (binaryInfoHash) {
+        if (typeof binaryInfoHash !== 'string' || binaryInfoHash.length !== 20)
           throw new Error('invalid info_hash')
-        }
+        return common.binaryToHex(binaryInfoHash)
       })
     }
 
-    return params
   } else {
-    return null
+    throw new Error('Invalid action in HTTP request: ' + params.action)
   }
+
+  return params
 }

lib/parse_udp.js

@@ -5,13 +5,11 @@ var ipLib = require('ip')
 var common = require('./common')
 
 function parseUdpRequest (msg, rinfo) {
-  if (msg.length < 16) {
+  if (msg.length < 16)
     throw new Error('received packet is too short')
-  }
 
-  if (rinfo.family !== 'IPv4') {
+  if (rinfo.family !== 'IPv4')
     throw new Error('udp tracker does not support IPv6')
-  }
 
   var params = {
     connectionId: msg.slice(0, 8), // 64-bit
@@ -20,41 +18,46 @@ function parseUdpRequest (msg, rinfo) {
   }
 
   // TODO: randomize
-  if (!bufferEqual(params.connectionId, common.CONNECTION_ID)) {
+  if (!bufferEqual(params.connectionId, common.CONNECTION_ID))
     throw new Error('received packet with invalid connection id')
-  }
 
   if (params.action === common.ACTIONS.CONNECT) {
     // No further params
+
   } else if (params.action === common.ACTIONS.ANNOUNCE) {
-    params.info_hash = msg.slice(16, 36).toString('binary') // 20 bytes
-    params.peer_id = msg.slice(36, 56).toString('utf8') // 20 bytes
+    params.info_hash = msg.slice(16, 36).toString('hex') // 20 bytes
+    params.peer_id = msg.slice(36, 56).toString('hex') // 20 bytes
     params.downloaded = fromUInt64(msg.slice(56, 64)) // TODO: track this?
     params.left = fromUInt64(msg.slice(64, 72))
     params.uploaded = fromUInt64(msg.slice(72, 80)) // TODO: track this?
-    params.event = msg.readUInt32BE(80)
-    params.event = common.EVENT_IDS[params.event]
+
+    params.event = common.EVENT_IDS[msg.readUInt32BE(80)]
     if (!params.event) throw new Error('invalid event') // early return
-    params.ip = msg.readUInt32BE(84) // optional
-    params.ip = params.ip ?
-      ipLib.toString(params.ip) :
-      rinfo.address
+
+    var ip = msg.readUInt32BE(84) // optional
+    params.ip = ip
+      ? ipLib.toString(ip)
+      : rinfo.address
+
     params.key = msg.readUInt32BE(88) // TODO: what is this for?
-    params.numwant = msg.readUInt32BE(92) // optional
+
     // never send more than MAX_ANNOUNCE_PEERS or else the UDP packet will get bigger than
     // 512 bytes which is not safe
-    params.numwant = Math.min(params.numwant || common.NUM_ANNOUNCE_PEERS, common.MAX_ANNOUNCE_PEERS)
+    params.numwant = Math.min(
+      msg.readUInt32BE(92) || common.NUM_ANNOUNCE_PEERS, // optional
+      common.MAX_ANNOUNCE_PEERS
+    )
+
     params.port = msg.readUInt16BE(96) || rinfo.port // optional
     params.addr = params.ip + ':' + params.port // TODO: ipv6 brackets
     params.compact = 1 // udp is always compact
 
   } else if (params.action === common.ACTIONS.SCRAPE) { // scrape message
-    params.info_hash = msg.slice(16, 36).toString('binary') // 20 bytes
-
     // TODO: support multiple info_hash scrape
-    if (msg.length > 36) {
-      throw new Error('multiple info_hash scrape not supported')
-    }
+    if (msg.length > 36) throw new Error('multiple info_hash scrape not supported')
+
+    params.info_hash = [ msg.slice(16, 36).toString('hex') ] // 20 bytes
+
   } else {
     throw new Error('Invalid action in UDP packet: ' + params.action)
   }

server.js

@@ -54,7 +54,7 @@ function Server (opts) {
   // default to starting an http server unless the user explictly says no
   if (opts.http !== false) {
     self._httpServer = http.createServer()
-    self._httpServer.on('request', self._onHttpRequest.bind(self))
+    self._httpServer.on('request', self.onHttpRequest.bind(self))
     self._httpServer.on('error', self._onError.bind(self))
     self._httpServer.on('listening', onListening)
   }
@@ -115,24 +115,20 @@ Server.prototype.close = function (cb) {
   }
 }
 
-Server.prototype.getSwarm = function (binaryInfoHash) {
+Server.prototype.getSwarm = function (infoHash) {
   var self = this
-  if (Buffer.isBuffer(binaryInfoHash)) binaryInfoHash = binaryInfoHash.toString('binary')
-  var swarm = self.torrents[binaryInfoHash]
-  if (!swarm) {
-    swarm = self.torrents[binaryInfoHash] = new Swarm(binaryInfoHash, this)
-  }
+  if (Buffer.isBuffer(infoHash)) infoHash = infoHash.toString('hex')
+  var swarm = self.torrents[infoHash]
+  if (!swarm) swarm = self.torrents[infoHash] = new Swarm(infoHash, this)
   return swarm
 }
 
-Server.prototype._onHttpRequest = function (req, res) {
+Server.prototype.onHttpRequest = function (req, res) {
   var self = this
 
   var params
   try {
-    params = parseHttpRequest(req, {
-      trustProxy: self._trustProxy
-    })
+    params = parseHttpRequest(req, { trustProxy: self._trustProxy })
   } catch (err) {
     debug('sent error %s', err.message)
     res.end(bencode.encode({
@@ -142,7 +138,7 @@ Server.prototype._onHttpRequest = function (req, res) {
     // even though it's an error for the client, it's just a warning for the server.
     // don't crash the server because a client sent bad data :)
     self.emit('warning', err)
-    
+
     return
   }
 
@@ -225,28 +221,12 @@ Server.prototype._onAnnounce = function (params, cb) {
 Server.prototype._onScrape = function (params, cb) {
   var self = this
 
-  if (typeof params.info_hash === 'string') {
-    params.info_hash = [ params.info_hash ]
-  } else if (params.info_hash == null) {
+  if (params.info_hash == null) {
     // if info_hash param is omitted, stats for all torrents are returned
     // TODO: make this configurable!
     params.info_hash = Object.keys(self.torrents)
   }
 
-  if (!Array.isArray(params.info_hash)) {
-    var err = new Error('invalid info_hash')
-    self.emit('warning', err)
-    return cb(err)
-  }
-
-  var response = {
-    action: common.ACTIONS.SCRAPE,
-    files: {},
-    flags: {
-      min_request_interval: self._intervalMs
-    }
-  }
-
   series(params.info_hash.map(function (infoHash) {
     var swarm = self.getSwarm(infoHash)
     return function (cb) {
@@ -261,8 +241,14 @@ Server.prototype._onScrape = function (params, cb) {
   }), function (err, results) {
     if (err) return cb(err)
 
+    var response = {
+      action: common.ACTIONS.SCRAPE,
+      files: {},
+      flags: { min_request_interval: self._intervalMs }
+    }
+
     results.forEach(function (result) {
-      response.files[result.infoHash] = {
+      response.files[common.hexToBinary(result.infoHash)] = {
         complete: result.complete,
         incomplete: result.incomplete,
         downloaded: result.complete // TODO: this only provides a lower-bound
@@ -273,7 +259,6 @@ Server.prototype._onScrape = function (params, cb) {
   })
 }
 
-
 function makeUdpPacket (params) {
   switch (params.action) {
     case common.ACTIONS.CONNECT:

test/server.js

@@ -2,9 +2,9 @@ var Client = require('../')
 var Server = require('../').Server
 var test = require('tape')
 
-var infoHash = new Buffer('4cb67059ed6bd08362da625b3ae77f6f4a075705', 'hex')
-var peerId = '01234567890123456789'
-var peerId2 = '12345678901234567890'
+var infoHash = '4cb67059ed6bd08362da625b3ae77f6f4a075705'
+var peerId = new Buffer('01234567890123456789')
+var peerId2 = new Buffer('12345678901234567890')
 var torrentLength = 50000
 
 function serverTest (t, serverType) {
@@ -52,7 +52,7 @@ function serverTest (t, serverType) {
       t.deepEqual(server.getSwarm(infoHash).peers['127.0.0.1:6881'], {
         ip: '127.0.0.1',
         port: 6881,
-        peerId: peerId
+        peerId: peerId.toString('hex')
       })
 
       client.complete()