Merge pull request #3 from eordano/sync

Sync

lib/blockchain.js

@@ -0,0 +1,45 @@
+'use strict';
+
+var bitcore = require('bitcore');
+var $ = bitcore.util.preconditions;
+var _ = bitcore.deps._;
+
+function BlockChain() {
+  this.tip = null;
+  this.headers = {};
+  this.next = {};
+  this.prev = {};
+}
+
+BlockChain.fromObject = function(obj) {
+  var blockchain = new BlockChain();
+  blockchain.tip = obj.tip;
+  blockchain.headers = obj.headers;
+  blockchain.next = obj.next;
+  blockchain.prev = obj.prev;
+  return blockchain;
+};
+
+BlockChain.prototype.setTip = function(block) {
+  $.checkArgument(block instanceof bitcore.Block, 'Argument is not a Block instance');
+  this.tip = block.hash;
+  this.headers[block.hash] = block.header;
+  var prevHash = bitcore.util.buffer.reverse(block.header.prevHash).toString('hex');
+  this.next[prevHash] = block.hash;
+  this.prev[block.hash] = prevHash;
+};
+
+BlockChain.prototype.toObject = function() {
+  return {
+    tip: this.tip,
+    headers: _.map(this.headers, function(header) { return header.toObject(); }),
+    next: this.next,
+    prev: this.prev
+  };
+};
+
+BlockChain.prototype.toJSON = function() {
+  return JSON.stringify(this.toObject());
+};
+
+module.exports = BlockChain;

lib/data/genesis.js

@@ -0,0 +1,13 @@
+module.exports = {
+  livenet: new Buffer('010000000000000000000000000000000000000000000000000000000000' +
+                      '0000000000003ba3edfd7a7b12b27ac72c3e67768f617fc81bc3888a5132' +
+                      '3a9fb8aa4b1e5e4a29ab5f49ffff001d1dac2b7c01010000000100000000' +
+                      '00000000000000000000000000000000000000000000000000000000ffff' +
+                      'ffff4d04ffff001d0104455468652054696d65732030332f4a616e2f3230' +
+                      '3039204368616e63656c6c6f72206f6e206272696e6b206f66207365636f' +
+                      '6e64206261696c6f757420666f722062616e6b73ffffffff0100f2052a01' +
+                      '000000434104678afdb0fe5548271967f1a67130b7105cd6a828e03909a6' +
+                      '7962e0ea1f61deb649f6bc3f4cef38c4f35504e51ec112de5c384df7ba0b' +
+                      '8d578a4c702b6bf11d5fac00000000', 'hex'),
+  testnet: new Buffer('')
+}

lib/networkmonitor.js

@@ -64,6 +64,11 @@ NetworkMonitor.prototype.setupPeer = function(peer) {
 
 };
 
+NetworkMonitor.prototype.requestBlocks = function(start) {
+  $.checkArgument(_.isString(start), 'start must be a block hash string');
+  this.peer.sendMessage(messages.GetBlocks([start]));
+};
+
 NetworkMonitor.prototype.start = function() {
   this.peer.connect();
 };
@@ -76,9 +81,4 @@ NetworkMonitor.prototype.abort = function(reason) {
   throw reason;
 };
 
-NetworkMonitor.prototype.syncFrom = function(start) {
-  $.checkArgument(_.isString(start), 'start must be a block hash string');
-  this.peer.sendMessage(messages.GetBlocks([start]));
-};
-
 module.exports = NetworkMonitor;

lib/node.js

@@ -19,6 +19,9 @@ var BlockService = require('./services/block');
 var TransactionService = require('./services/transaction');
 var AddressService = require('./services/address');
 
+var BlockChain = require('./blockchain');
+var genesisBlocks = require('./data/genesis');
+
 var BitcoreNode = function(bus, networkMonitor, blockService, transactionService, addressService) {
   $.checkArgument(bus);
   $.checkArgument(networkMonitor);
@@ -26,6 +29,8 @@ var BitcoreNode = function(bus, networkMonitor, blockService, transactionService
   this.bus = bus;
   this.networkMonitor = networkMonitor;
 
+  this.tip = null;
+
   this.addressService = addressService;
   this.transactionService = transactionService;
   this.blockService = blockService;
@@ -82,18 +87,17 @@ BitcoreNode.prototype.start = function() {
 };
 
 BitcoreNode.prototype.sync = function() {
-  var genesis = bitcore.Block.fromBuffer(bitcore.Networks.defaultNetwork.genesis);
+  var genesis = bitcore.Block.fromBuffer(genesisBlocks[bitcore.Networks.defaultNetwork.name]);
   var self = this;
   this.networkMonitor.on('ready', function() {
-    console.log('ready');
-    self.blockService.getLatest().then(function(latest) {
-        var start = genesis.hash;
-        console.log('latest', latest);
-        if (latest) {
-          start = latest.hash;
+    self.blockService.getBlockchain().then(function(blockchain) {
+        if (blockchain) {
+          self.blockchain = blockchain;
+        } else {
+          self.blockchain = new BlockChain();
+          self.blockchain.setTip(genesis);
         }
-        console.log('Starting sync from', start);
-        self.networkMonitor.syncFrom(start);
+        self.networkMonitor.requestBlocks(self.blockchain.tip);
       })
       .catch(function(err) {
         self.networkMonitor.stop();

lib/services/block.js

@@ -39,7 +39,8 @@ var Index = {
   prev: 'prev-', // prev-<hash> -> parent hash
   next: 'nxt-', // nxt-<hash> -> hash for the next block in the main chain that is a child
   height: 'bh-', // bh-<hash> -> height (-1 means disconnected)
-  tip: 'tip' // tip -> { hash: hex, height: int }, the latest tip
+  tip: 'tip', // tip -> { hash: hex, height: int }, the latest tip
+  blockchain: 'chain'
 };
 _.extend(Index, {
   getNextBlock: helper(Index.next),
@@ -381,4 +382,26 @@ BlockService.prototype.getBlockForTransaction = function(transaction) {
   });
 };
 
+BlockService.prototype.getBlockchain = function() {
+  var self = this;
+  return new Promise(function(resolve, reject) {
+    self.database.getAsync(Index.blockchain).then(function(blockchain) {
+      blockchain = BlockChain.fromObject(JSON.parse(blockchain));
+      return resolve(blockchain);
+    }).catch(function(arg) {
+      if (arg.message.indexOf('Key not found in database') !== -1) {
+        return resolve();
+      }
+      return reject(arg);
+    });
+  });
+};
+
+BlockService.prototype.saveBlockchain = function(blockchain) {
+  return this.database.putAsync({
+    key: Index.blockchain,
+    value: blockchain.toJSON()
+  });
+};
+
 module.exports = BlockService;