fix: modernize

bin/cmd.js

@@ -39,7 +39,7 @@ if (argv.version) {
 }
 
 if (argv.help) {
-  console.log(function () {
+  console.log((() => {
   /*
   bittorrent-tracker - Start a bittorrent tracker server
 
@@ -64,7 +64,7 @@ if (argv.help) {
     -v, --version                 print the current version
 
   */
-  }.toString().split(/\n/).slice(2, -2).join('\n'))
+  }).toString().split(/\n/).slice(2, -2).join('\n'))
   process.exit(0)
 }
 
@@ -85,23 +85,23 @@ const server = new Server({
   ws: argv.ws
 })
 
-server.on('error', function (err) {
-  if (!argv.silent) console.error('ERROR: ' + err.message)
+server.on('error', err => {
+  if (!argv.silent) console.error(`ERROR: ${err.message}`)
 })
-server.on('warning', function (err) {
-  if (!argv.quiet) console.log('WARNING: ' + err.message)
+server.on('warning', err => {
+  if (!argv.quiet) console.log(`WARNING: ${err.message}`)
 })
-server.on('update', function (addr) {
-  if (!argv.quiet) console.log('update: ' + addr)
+server.on('update', addr => {
+  if (!argv.quiet) console.log(`update: ${addr}`)
 })
-server.on('complete', function (addr) {
-  if (!argv.quiet) console.log('complete: ' + addr)
+server.on('complete', addr => {
+  if (!argv.quiet) console.log(`complete: ${addr}`)
 })
-server.on('start', function (addr) {
-  if (!argv.quiet) console.log('start: ' + addr)
+server.on('start', addr => {
+  if (!argv.quiet) console.log(`start: ${addr}`)
 })
-server.on('stop', function (addr) {
-  if (!argv.quiet) console.log('stop: ' + addr)
+server.on('stop', addr => {
+  if (!argv.quiet) console.log(`stop: ${addr}`)
 })
 
 const hostname = {
@@ -110,35 +110,35 @@ const hostname = {
   udp6: argv['udp6-hostname']
 }
 
-server.listen(argv.port, hostname, function () {
+server.listen(argv.port, hostname, () => {
   if (server.http && argv.http && !argv.quiet) {
     const httpAddr = server.http.address()
     const httpHost = httpAddr.address !== '::' ? httpAddr.address : 'localhost'
     const httpPort = httpAddr.port
-    console.log('HTTP tracker: http://' + httpHost + ':' + httpPort + '/announce')
+    console.log(`HTTP tracker: http://${httpHost}:${httpPort}/announce`)
   }
   if (server.udp && !argv.quiet) {
     const udpAddr = server.udp.address()
     const udpHost = udpAddr.address
     const udpPort = udpAddr.port
-    console.log('UDP tracker: udp://' + udpHost + ':' + udpPort)
+    console.log(`UDP tracker: udp://${udpHost}:${udpPort}`)
   }
   if (server.udp6 && !argv.quiet) {
     const udp6Addr = server.udp6.address()
     const udp6Host = udp6Addr.address !== '::' ? udp6Addr.address : 'localhost'
     const udp6Port = udp6Addr.port
-    console.log('UDP6 tracker: udp://' + udp6Host + ':' + udp6Port)
+    console.log(`UDP6 tracker: udp://${udp6Host}:${udp6Port}`)
   }
   if (server.ws && !argv.quiet) {
     const wsAddr = server.http.address()
     const wsHost = wsAddr.address !== '::' ? wsAddr.address : 'localhost'
     const wsPort = wsAddr.port
-    console.log('WebSocket tracker: ws://' + wsHost + ':' + wsPort)
+    console.log(`WebSocket tracker: ws://${wsHost}:${wsPort}`)
   }
   if (server.http && argv.stats && !argv.quiet) {
     const statsAddr = server.http.address()
     const statsHost = statsAddr.address !== '::' ? statsAddr.address : 'localhost'
     const statsPort = statsAddr.port
-    console.log('Tracker stats: http://' + statsHost + ':' + statsPort + '/stats')
+    console.log(`Tracker stats: http://${statsHost}:${statsPort}/stats`)
   }
 })

client.js

@@ -281,9 +281,7 @@ Client.scrape = (opts, cb) => {
   })
 
   opts.infoHash = Array.isArray(opts.infoHash)
-    ? opts.infoHash.map(infoHash => {
-        return Buffer.from(infoHash, 'hex')
-      })
+    ? opts.infoHash.map(infoHash => Buffer.from(infoHash, 'hex'))
     : Buffer.from(opts.infoHash, 'hex')
   client.scrape({ infoHash: opts.infoHash })
   return client

examples/express-embed/server.js

@@ -13,7 +13,7 @@ const server = new Server({
   http: false, // we do our own
   udp: false, // not interested
   ws: false, // not interested
-  filter: function (params) {
+  filter (params) {
     // black/whitelist for disallowing/allowing specific clients [default=allow all]
     // this example only allows the uTorrent client
     const client = params.peer_id[1] + params.peer_id[2]

lib/client/http-tracker.js

@@ -17,7 +17,7 @@ const HTTP_SCRAPE_SUPPORT = /\/(announce)[^/]*$/
  * @param {Object} opts         options object
  */
 class HTTPTracker extends Tracker {
-  constructor (client, announceUrl, opts) {
+  constructor (client, announceUrl) {
     super(client, announceUrl)
 
     debug('new http tracker %s', announceUrl)
@@ -62,9 +62,7 @@ class HTTPTracker extends Tracker {
     }
 
     const infoHashes = (Array.isArray(opts.infoHash) && opts.infoHash.length > 0)
-      ? opts.infoHash.map(infoHash => {
-          return infoHash.toString('binary')
-        })
+      ? opts.infoHash.map(infoHash => infoHash.toString('binary'))
       : (opts.infoHash && opts.infoHash.toString('binary')) || this.client._infoHashBinary
     const params = {
       info_hash: infoHashes

lib/client/udp-tracker.js

@@ -16,7 +16,7 @@ const Tracker = require('./tracker')
  * @param {Object} opts         options object
  */
 class UDPTracker extends Tracker {
-  constructor (client, announceUrl, opts) {
+  constructor (client, announceUrl) {
     super(client, announceUrl)
     debug('new udp tracker %s', announceUrl)
 
@@ -181,7 +181,7 @@ class UDPTracker extends Tracker {
             return onError(new Error('invalid scrape message'))
           }
           const infoHashes = (Array.isArray(opts.infoHash) && opts.infoHash.length > 0)
-            ? opts.infoHash.map(infoHash => { return infoHash.toString('hex') })
+            ? opts.infoHash.map(infoHash => infoHash.toString('hex'))
             : [(opts.infoHash && opts.infoHash.toString('hex')) || self.client.infoHash]
 
           for (let i = 0, len = (msg.length - 8) / 12; i < len; i += 1) {

lib/client/websocket-tracker.js

@@ -17,7 +17,7 @@ const RECONNECT_VARIANCE = 5 * 60 * 1000
 const OFFER_TIMEOUT = 50 * 1000
 
 class WebSocketTracker extends Tracker {
-  constructor (client, announceUrl, opts) {
+  constructor (client, announceUrl) {
     super(client, announceUrl)
     debug('new websocket tracker %s', announceUrl)
 
@@ -76,9 +76,7 @@ class WebSocketTracker extends Tracker {
     }
 
     const infoHashes = (Array.isArray(opts.infoHash) && opts.infoHash.length > 0)
-      ? opts.infoHash.map(infoHash => {
-          return infoHash.toString('binary')
-        })
+      ? opts.infoHash.map(infoHash => infoHash.toString('binary'))
       : (opts.infoHash && opts.infoHash.toString('binary')) || this.client._infoHashBinary
     const params = {
       action: 'scrape',

lib/common-node.js

@@ -50,21 +50,17 @@ exports.toUInt32 = toUInt32
  * @param  {string} q
  * @return {Object}
  */
-exports.querystringParse = function (q) {
-  return querystring.parse(q, null, null, { decodeURIComponent: unescape })
-}
+exports.querystringParse = q => querystring.parse(q, null, null, { decodeURIComponent: unescape })
 
 /**
  * `querystring.stringify` using `escape` instead of encodeURIComponent, since bittorrent
  * clients send non-UTF8 querystrings
  * @param  {Object} obj
  * @return {string}
  */
-exports.querystringStringify = function (obj) {
+exports.querystringStringify = obj => {
   let ret = querystring.stringify(obj, null, null, { encodeURIComponent: escape })
-  ret = ret.replace(/[@*/+]/g, function (char) {
-    // `escape` doesn't encode the characters @*/+ so we do it manually
-    return '%' + char.charCodeAt(0).toString(16).toUpperCase()
-  })
+  ret = ret.replace(/[@*/+]/g, char => // `escape` doesn't encode the characters @*/+ so we do it manually
+  `%${char.charCodeAt(0).toString(16).toUpperCase()}`)
   return ret
 }

lib/common.js

@@ -5,14 +5,14 @@
 exports.DEFAULT_ANNOUNCE_PEERS = 50
 exports.MAX_ANNOUNCE_PEERS = 82
 
-exports.binaryToHex = function (str) {
+exports.binaryToHex = str => {
   if (typeof str !== 'string') {
     str = String(str)
   }
   return Buffer.from(str, 'binary').toString('hex')
 }
 
-exports.hexToBinary = function (str) {
+exports.hexToBinary = str => {
   if (typeof str !== 'string') {
     str = String(str)
   }
@@ -31,7 +31,7 @@ exports.hexToBinary = function (str) {
 // Bug reports:
 // - Chrome: https://bugs.chromium.org/p/chromium/issues/detail?id=734880
 // - Firefox: https://bugzilla.mozilla.org/show_bug.cgi?id=1374505
-exports.parseUrl = function (str) {
+exports.parseUrl = str => {
   const url = new URL(str.replace(/^udp:/, 'http:'))
 
   if (str.match(/^udp:/)) {

lib/server/parse-http.js

@@ -36,23 +36,23 @@ function parseHttpRequest (req, opts) {
     params.ip = opts.trustProxy
       ? req.headers['x-forwarded-for'] || req.connection.remoteAddress
       : req.connection.remoteAddress.replace(common.REMOVE_IPV4_MAPPED_IPV6_RE, '') // force ipv4
-    params.addr = (common.IPV6_RE.test(params.ip) ? '[' + params.ip + ']' : params.ip) + ':' + params.port
+    params.addr = `${common.IPV6_RE.test(params.ip) ? `[${params.ip}]` : params.ip}:${params.port}`
 
     params.headers = req.headers
   } else if (opts.action === 'scrape' || s[0] === '/scrape') {
     params.action = common.ACTIONS.SCRAPE
 
     if (typeof params.info_hash === 'string') params.info_hash = [params.info_hash]
     if (Array.isArray(params.info_hash)) {
-      params.info_hash = params.info_hash.map(function (binaryInfoHash) {
+      params.info_hash = params.info_hash.map(binaryInfoHash => {
         if (typeof binaryInfoHash !== 'string' || binaryInfoHash.length !== 20) {
           throw new Error('invalid info_hash')
         }
         return common.binaryToHex(binaryInfoHash)
       })
     }
   } else {
-    throw new Error('invalid action in HTTP request: ' + req.url)
+    throw new Error(`invalid action in HTTP request: ${req.url}`)
   }
 
   return params

lib/server/parse-udp.js

@@ -44,7 +44,7 @@ function parseUdpRequest (msg, rinfo) {
     )
 
     params.port = msg.readUInt16BE(96) || rinfo.port // optional
-    params.addr = params.ip + ':' + params.port // TODO: ipv6 brackets
+    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
     if ((msg.length - 16) % 20 !== 0) throw new Error('invalid scrape message')
@@ -54,7 +54,7 @@ function parseUdpRequest (msg, rinfo) {
       params.info_hash.push(infoHash)
     }
   } else {
-    throw new Error('Invalid action in UDP packet: ' + params.action)
+    throw new Error(`Invalid action in UDP packet: ${params.action}`)
   }
 
   return params

lib/server/parse-websocket.js

@@ -41,15 +41,15 @@ function parseWebSocketRequest (socket, opts, params) {
 
     if (typeof params.info_hash === 'string') params.info_hash = [params.info_hash]
     if (Array.isArray(params.info_hash)) {
-      params.info_hash = params.info_hash.map(function (binaryInfoHash) {
+      params.info_hash = params.info_hash.map(binaryInfoHash => {
         if (typeof binaryInfoHash !== 'string' || binaryInfoHash.length !== 20) {
           throw new Error('invalid info_hash')
         }
         return common.binaryToHex(binaryInfoHash)
       })
     }
   } else {
-    throw new Error('invalid action in WS request: ' + params.action)
+    throw new Error(`invalid action in WS request: ${params.action}`)
   }
 
   // On first parse, save important data from `socket.upgradeReq` and delete it
@@ -60,7 +60,7 @@ function parseWebSocketRequest (socket, opts, params) {
       : socket.upgradeReq.connection.remoteAddress.replace(common.REMOVE_IPV4_MAPPED_IPV6_RE, '') // force ipv4
     socket.port = socket.upgradeReq.connection.remotePort
     if (socket.port) {
-      socket.addr = (common.IPV6_RE.test(socket.ip) ? '[' + socket.ip + ']' : socket.ip) + ':' + socket.port
+      socket.addr = `${common.IPV6_RE.test(socket.ip) ? `[${socket.ip}]` : socket.ip}:${socket.port}`
     }
 
     socket.headers = socket.upgradeReq.headers