Added the checkpoints back in.

lib/services/block/index.js

@@ -482,6 +482,7 @@ BlockService.prototype._onBlock = function(block) {
 BlockService.prototype._setListeners = function() {
 
   this._header.once('headers', this._onAllHeaders.bind(this));
+  this._header.on('reorg', this._handleReorg.bind(this));
 
 };
 

lib/services/header/index.js

@@ -24,6 +24,7 @@ var HeaderService = function(options) {
 
   this.subscriptions = {};
   this.subscriptions.block = [];
+  this._checkpoint = options.checkpoint || 2000;
   this.GENESIS_HASH = constants.BITCOIN_GENESIS_HASH[this.node.network];
 };
 
@@ -93,9 +94,10 @@ HeaderService.prototype.start = function(callback) {
     function(tip, next) {
       self._tip = tip;
       self._originalTip = {
-        height: self._tip.height,
-        hash: self._tip.hash
+        hash: self._tip.hash,
+        height: self._tip.height
       };
+
       if (self._tip.height === 0) {
 
         var genesisHeader = {
@@ -128,9 +130,6 @@ HeaderService.prototype.start = function(callback) {
       return callback(err);
     }
 
-    if (self._headers.size > 0) {
-      self._tip.hash = self._headers.getLastIndex().hash;
-    }
     self._setListeners();
     self._startSubscriptions();
     callback();
@@ -224,7 +223,7 @@ HeaderService.prototype._onHeaders = function(headers) {
       value: self._encoding.encodeHeaderValue(header)
     });
     prevHeader = header;
-    self._headers.set(header.hash, header);
+    self._headers.set(header.hash, header, header.height);
   }
 
   var tipOps = utils.encodeTip(self._tip, self.name);
@@ -243,24 +242,33 @@ HeaderService.prototype._onHeaders = function(headers) {
 
     log.debug('Header Service: download complete.');
 
-    // have we reorg'ed since we've been shutdown?
-    if (self._tip.height > 0) {
-
-      var headerHash = self._headers.getIndex(self._tip.height).hash;
-      if (self._tip.hash !== headerHash) {
-
-        self.emit('reorg', headerHash, self._headers);
-        return;
-
-      }
+    // at this point, we can check our header list to see if our starting tip diverged from the tip
+    // that we have now
+    if (self._detectReorg()) {
+      self._handleReorg();
+      return;
     }
 
     log.debug('Header Service: emitting headers to block service.');
     self.emit('headers', self._headers);
+
   });
 
 };
 
+HeaderService.prototype._detectReorg = function() {
+  // is our original tip's height and hash the same after we rewound by the checkpoint amount of blocks
+  // and re-imported? If so, then we've reorg'ed since we've been shut down.
+  if (this._originalTip.hash !== this._headers.getIndex(this._originalTip.height).hash) {
+    return true;
+  }
+  return false;
+};
+
+HeaderService.prototype._handleReorg = function() {
+  this.emit('reorg', this._headers.getIndex(this._originalTip.height).hash, this._headers);
+};
+
 HeaderService.prototype._setListeners = function() {
 
   this._p2p.once('bestHeight', this._onBestHeight.bind(this));
@@ -287,10 +295,10 @@ HeaderService.prototype._startSync = function() {
 
 HeaderService.prototype._sync = function() {
 
-    log.debug('Header Service: download progress: ' + this._tip.height + '/' +
-      this._bestHeight + '  (' + (this._tip.height / this._bestHeight*100).toFixed(2) + '%)');
+  log.debug('Header Service: download progress: ' + this._tip.height + '/' +
+    this._bestHeight + '  (' + (this._tip.height / this._bestHeight*100).toFixed(2) + '%)');
 
-    this._p2p.getHeaders({ startHash: this._tip.hash });
+  this._p2p.getHeaders({ startHash: this._tip.hash });
 
 };
 
@@ -302,8 +310,14 @@ HeaderService.prototype._getPersistedHeaders = function(callback) {
 
   var self = this;
 
+  var startingHeight = self._tip.height;
+  if (self._tip.height > self._checkpoint) {
+    self._tip.height -= self._checkpoint;
+  }
+  var removalOps = [];
+
   var start = self._encoding.encodeHeaderKey(0);
-  var end = self._encoding.encodeHeaderKey(self._tip.height + 1);
+  var end = self._encoding.encodeHeaderKey(startingHeight + 1);
 
   log.debug('Getting persisted headers from genesis block to block ' + (self._tip.height + 1));
 
@@ -320,14 +334,24 @@ HeaderService.prototype._getPersistedHeaders = function(callback) {
   });
 
   stream.on('data', function(data) {
-    self._headers.set(self._encoding.decodeHeaderKey(data.key).hash, self._encoding.decodeHeaderValue(data.value));
+    var header  = self._encoding.decodeHeaderValue(data.value);
+    // any records with a height greater than our current tip height can be scheduled for removal
+    if (header.height > self._tip.height) {
+      removalOps.push({
+        type: 'del',
+        key: data.key
+      });
+      return;
+    }
+    self._headers.set(self._encoding.decodeHeaderKey(data.key).hash, header, header.height);
   });
 
   stream.on('end', function() {
     if (streamErr) {
       return streamErr;
     }
-    callback();
+    self._tip.hash = self._headers.getIndex(self._tip.height).hash;
+    self._db.batch(removalOps, callback);
   });
 
 };

lib/utils.js

@@ -76,9 +76,14 @@ utils.SimpleMap = function SimpleMap() {
     return array[object[key]];
   };
 
-  this.set = function (key, value) {
+  this.set = function (key, value, pos) {
     object[key] = array.length;
-    array.push(value);
+
+    if (pos >= 0) {
+      array[pos] = value;
+    } else {
+      array.push(value);
+    }
 
     this.size = array.length;
     this.length = array.length;