Merge remote-tracking branch 'gordonwritescode/feature/peer-discovery'

examples/PeerDiscovery.js

@@ -0,0 +1,4 @@
+var PeerManager = require('../lib/PeerManager');
+var peerman     = new PeerManager();
+
+peerman.discover({ limit: 12 }).start();

lib/Peer.js

@@ -34,8 +34,8 @@ function Peer(host, port, services) {
 Peer.IPV6_IPV4_PADDING = new Buffer([0,0,0,0,0,0,0,0,0,0,255,255]);
 
 Peer.prototype.createConnection = function () {
-  var c = Net.createConnection(this.port, this.host);
-  return c;
+  this.connection = Net.createConnection(this.port, this.host);
+  return this.connection;
 };
 
 Peer.prototype.getHostAsBuffer = function () {

lib/PeerManager.js

@@ -1,10 +1,8 @@
-
-
 var imports         = require('soop').imports();
+var extend          = imports.extend || require('extend');
 var log             = imports.log || require('../util/log');
 var bitcoreDefaults = imports.config || require('../config');
 var Connection      = imports.Connection || require ('./Connection');
-
 var Peer            = imports.Peer || require('./Peer');
 
 GetAdjustedTime = imports.GetAdjustedTime || function () {
@@ -13,11 +11,13 @@ GetAdjustedTime = imports.GetAdjustedTime || function () {
 };
 
 function PeerManager(config) {
-  this.config = config || bitcoreDefaults;
+  // extend defaults with config
+  this.config = extend(true, config || {}, bitcoreDefaults);
   this.active = false;
   this.timer = null;
 
   this.peers = [];
+  this.pool = [];
   this.connections = [];
   this.isConnected = false;
   this.peerDiscovery = false;
@@ -26,6 +26,12 @@ function PeerManager(config) {
   this.interval = 5000;
   this.minConnections = 8;
   this.minKnownPeers = 10;
+
+  // keep track of tried seeds and results
+  this.seeds = {
+    resolved: [],
+    failed: []
+  };
 }
 
 PeerManager.parent = imports.parent || require('events').EventEmitter;
@@ -61,6 +67,13 @@ PeerManager.prototype.addPeer = function(peer, port) {
   }
 };
 
+PeerManager.prototype.removePeer = function(peer) {
+  var index  = this.peers.indexOf(peer);
+  var exists = !!~index;
+  if (exists) this.peers.splice(index, 1);
+  return exists;
+};
+
 PeerManager.prototype.checkStatus = function checkStatus() {
   // Make sure we are connected to all forcePeers
   if(this.peers.length) {
@@ -77,6 +90,13 @@ PeerManager.prototype.checkStatus = function checkStatus() {
       }
     });
 
+    // for debug purposes, print how many of our peers are actually connected
+    var connected = 0
+    this.peers.forEach(function(p) { 
+      if (p.connection && !p.connection._connecting) connected++ 
+    });
+    log.info(connected + ' of ' + this.peers.length + ' peers connected');
+
     Object.keys(peerIndex).forEach(function(i) {
       this.connectTo(peerIndex[i]);
     }.bind(this));
@@ -84,7 +104,7 @@ PeerManager.prototype.checkStatus = function checkStatus() {
 };
 
 PeerManager.prototype.connectTo = function(peer) {
-  log.info('connecting to '+peer);
+  log.info('connecting to ' + peer);
   try {
     return this.addConnection(peer.createConnection(), peer);
   } catch (e) {
@@ -174,10 +194,16 @@ PeerManager.prototype.handleError = function(e) {
 };
 
 PeerManager.prototype.handleDisconnect = function(e) {
-  log.info('disconnected from peer '+e.peer);
+  log.info('disconnected from peer ' + e.peer);
   var i = this.connections.indexOf(e.conn);
   if(i != -1) this.connections.splice(i, 1);
 
+  this.removePeer(e.peer);
+  if (this.pool.length) {
+    log.info('replacing peer using the pool of ' + this.pool.length + ' seeds');
+    this.addPeer(this.pool.pop());
+  }
+
   if(!this.connections.length) {
     this.emit('netDisconnected');
     this.isConnected = false;
@@ -212,4 +238,72 @@ PeerManager.prototype.getActiveConnections = function () {
   return this.connections.slice(0);
 };
 
+PeerManager.prototype.discover = function(options, callback) {
+  var self     = this;
+  var async    = imports.async || require('async');
+  var dns      = imports.dns || require('dns');
+  var networks = imports.networks || require('../networks');
+  var seeds    = networks[self.config.network].dnsSeeds;
+
+  self.limit = options.limit || 12;
+
+  var dnsExecutor = seeds.map(function(seed) {
+    return function(done) {
+      // have we already resolved this seed?
+      if (~self.seeds.resolved.indexOf(seed)) {
+        // if so, just pass back cached peer list
+        return done(null, self.seeds.results[seed]);
+      }
+
+      // has this seed failed to resolve?
+      if (~self.seeds.failed.indexOf(seed)) {
+        // if so, pass back empty results
+        return done(null, []);
+      }
+
+      log.info('resolving dns seed '+ seed);
+
+      dns.resolve(seed, function(err, peers) {
+        if (err) {
+          log.err('failed to resolve dns seed '+ seed, err);
+          self.seeds.failed.push(seed);
+          return done(null, []);
+        }
+
+        log.info('found '+ peers.length + ' peers from ' + seed);
+        self.seeds.resolved.push(seed);
+
+        // transform that list into a list of Peer instances
+        peers = peers.map(function(ip) {
+          return new Peer(ip, networks.defaultClientPort);
+        });
+
+        peers.forEach(function(p) {
+          if (self.peers.length < self.limit) self.addPeer(p);
+          else self.pool.push(p);
+        });
+
+        self.emit('peers', peers);
+
+        return done(null, peers);
+      });
+
+    };
+  });
+
+  // try resolving all seeds
+  async.parallel(dnsExecutor, function(err, results) {
+    var peers = [];
+
+    // consolidate all resolved peers into one list
+    results.forEach(function(peerlist) {
+      peers = peers.concat(peerlist);
+    });
+
+    if (typeof callback === 'function') callback(null, peers);
+  });
+
+  return self;
+};
+
 module.exports = require('soop')(PeerManager);

networks.js

@@ -19,7 +19,16 @@ exports.livenet = {
     prev_hash: buffertools.fill(new Buffer(32), 0),
     timestamp: 1231006505,
     bits: 486604799,
-  }
+  },
+  dnsSeeds: [
+    'seed.bitcoin.sipa.be',
+    'dnsseed.bluematt.me',
+    'dnsseed.bitcoin.dashjr.org',
+    'seed.bitcoinstats.com',
+    'seed.bitnodes.io',
+    'bitseed.xf2.org'
+  ],
+  defaultClientPort: 8333
 };
 
 exports.testnet = {
@@ -39,5 +48,10 @@ exports.testnet = {
     prev_hash: buffertools.fill(new Buffer(32), 0),
     timestamp: 1296688602,
     bits: 486604799,
-  }
+  },
+  dnsSeeds: [
+    'testnet-seed.bitcoin.petertodd.org',
+    'testnet-seed.bluematt.me'
+  ],
+  defaultClientPort: 18333
 };

package.json

@@ -70,7 +70,8 @@
     "socks5-client": "~0.3.6",
     "brfs": "=1.0.0",
     "chai": "=1.9.1",
-    "uglifyify": "=1.2.3"
+    "uglifyify": "=1.2.3",
+    "extend": "~1.2.1"
   },
   "devDependencies": {
     "grunt-contrib-watch": "~0.5.3",