Add FilterLoad, FilterAdd, and FilterClear Messages + BloomFilter

lib/bloomfilter.js

@@ -0,0 +1,47 @@
+'use strict';
+
+var bitcore = require('bitcore');
+var BloomFilter = require('bloom-filter');
+var BufferReader = bitcore.encoding.BufferReader;
+var BufferWriter = bitcore.encoding.BufferWriter;
+var $ = bitcore.util.preconditions;
+
+
+BloomFilter.fromBuffer = function fromBuffer(payload) {
+  var parser = new BufferReader(payload);
+  var data = parser.readVarLengthBuffer();
+  $.checkState(data.length <= BloomFilter.MAX_BLOOM_FILTER_SIZE,
+    'Filter data must be <= MAX_BLOOM_FILTER_SIZE bytes');
+  var nHashFuncs = parser.readUInt32LE();
+  $.checkState(nHashFuncs <= BloomFilter.MAX_HASH_FUNCS,
+    'Filter nHashFuncs must be <= MAX_HASH_FUNCS');
+  var nTweak = parser.readUInt32LE();
+  var nFlags = parser.readUInt8();
+
+  var vData = [];
+  var dataParser = new BufferReader(data);
+  for(var i = 0; i < data.length; i++) {
+    vData.push(dataParser.readUInt8());
+  }
+
+  return new BloomFilter({
+    vData: vData,
+    nHashFuncs: nHashFuncs,
+    nTweak: nTweak,
+    nFlags: nFlags
+  });
+}
+
+BloomFilter.prototype.toBuffer = function toBuffer() {
+  var bw = new BufferWriter();
+  bw.writeVarintNum(this.vData.length);
+  for(var i = 0; i < this.vData.length; i++) {
+    bw.writeUInt8(this.vData[i]);
+  }
+  bw.writeUInt32LE(this.nHashFuncs);
+  bw.writeUInt32LE(this.nTweak);
+  bw.writeUInt8(this.nFlags);
+  return bw.concat();
+};
+
+module.exports = BloomFilter;

lib/index.js

@@ -4,5 +4,6 @@
 module.exports = {
   Messages: require('./messages'),
   Peer: require('./peer'),
-  Pool: require('./pool')
+  Pool: require('./pool'),
+  BloomFilter: require('./bloomfilter')
 };

lib/messages.js

@@ -7,6 +7,7 @@
 var Buffers = require('buffers');
 var Put = require('bufferput');
 var util = require('util');
+var BloomFilter = require('./bloomfilter');
 
 var bitcore = require('bitcore');
 var _ = bitcore.deps._;
@@ -14,6 +15,7 @@ var _ = bitcore.deps._;
 var BlockHeaderModel = bitcore.BlockHeader;
 var BlockModel = bitcore.Block;
 var BufferReader = bitcore.encoding.BufferReader;
+var BufferWriter = bitcore.encoding.BufferWriter;
 var BufferUtil = bitcore.util.buffer;
 var $ = bitcore.util.preconditions;
 var Hash = bitcore.crypto.Hash;
@@ -826,6 +828,80 @@ function GetHeaders(starts, stop) {
 util.inherits(GetHeaders, GetBlocks);
 module.exports.GetHeaders = Message.COMMANDS.getheaders = GetHeaders;
 
+/**
+ * Request peer to apply a bloom filter to 'inv' messages sent back
+ *
+ * @name P2P.Message.filterload
+ * @param{BloomFilter} filter - a BloomFilter object
+ */
+function FilterLoad(filter) {
+  this.command = 'filterload';
+  $.checkArgument(_.isUndefined() || filter instanceof BloomFilter,
+    'BloomFilter object  or undefined required for FilterLoad');
+  this.filter = filter;
+  return this;
+}
+util.inherits(FilterLoad, Message);
+
+FilterLoad.prototype.fromBuffer = function(payload) {
+  this.filter = BloomFilter.fromBuffer(payload);
+  return this;
+};
+
+FilterLoad.prototype.getPayload = function() {
+  if(this.filter) {
+    return this.filter.toBuffer()
+  } else {
+    return BufferUtil.EMPTY_BUFFER;
+  }
+};
+
+module.exports.FilterLoad = Message.COMMANDS.filterload = FilterLoad;
+
+/**
+ * Request peer to add data to a bloom filter already set by 'filterload'
+ *
+ * @name P2P.Message.filteradd
+ * @param{Buffer} data - Array of bytes representing bloom filter data
+ */
+function FilterAdd(data) {
+  this.command = 'filteradd';
+  this.data = data || new Buffer(0,'hex');
+  return this;
+}
+util.inherits(FilterAdd, Message);
+
+FilterAdd.prototype.fromBuffer = function(payload) {
+  $.checkArgument(payload);
+  var parser = new BufferReader(payload);
+  this.data = parser.readVarLengthBuffer();
+  $.checkState(this.data.length <= BloomFilter.MAX_BLOOM_FILTER_SIZE,
+    'FilterAdd data must be <= 520 bytes');
+  this._checkFinished(parser);
+  return this;
+};
+
+FilterAdd.prototype.getPayload = function() {
+  var bw = new BufferWriter();
+  bw.writeVarintNum(this.data.length);
+  bw.write(this.data);
+  return bw.concat();
+};
+
+module.exports.FilterAdd = Message.COMMANDS.filterload = FilterAdd;
+
+/**
+ * Request peer to apply a bloom filter to 'inv' messages sent back
+ *
+ * @name P2P.Message.filterclear
+ */
+function FilterClear() {
+  this.command = 'filterclear';
+}
+util.inherits(FilterClear, Message);
+
+module.exports.FilterClear = Message.COMMANDS.filterclear = FilterClear;
+
 /**
  * Request for transactions on the mempool
  *

lib/pool.js

@@ -86,7 +86,8 @@ Pool.MaxConnectedPeers = 8;
 Pool.RetrySeconds = 30;
 Pool.PeerEvents = ['version', 'inv', 'getdata', 'ping', 'pong', 'addr',
   'getaddr', 'verack', 'reject', 'alert', 'headers', 'block',
-  'tx', 'getblocks', 'getheaders', 'error'
+  'tx', 'getblocks', 'getheaders', 'error', 'filterload', 'filteradd',
+  'filterclear'
 ];
 
 

package.json

@@ -53,6 +53,7 @@
   },
   "dependencies": {
     "bitcore": "^0.10.2",
+    "bloom-filter": "^0.1.1",
     "bufferput": "^0.1.2",
     "buffers": "^0.1.1",
     "socks5-client": "^0.3.6"

test/bloomfilter.js

@@ -0,0 +1,17 @@
+'use strict';
+
+var chai = require('chai');
+
+var Data = require('./data/messages');
+var P2P = require('../');
+var BloomFilter = P2P.BloomFilter;
+
+
+describe('BloomFilter', function() {
+  it('BloomFilter#fromBuffer and toBuffer methods work', function() {
+    var testPayload = Data.FILTERLOAD.payload;
+    var filter = new BloomFilter.fromBuffer(new Buffer(testPayload, 'hex'));
+    filter.toBuffer().toString('hex').should.equal(testPayload);
+  });
+
+});

test/data/messages.json

@@ -62,5 +62,17 @@
   "PONG": {
     "message": "f9beb4d9706f6e67000000000000000008000000c6466f1e6b86480ae969867c",
     "payload": "6b86480ae969867c"
+  },
+  "FILTERLOAD": {
+    "message": "f9beb4d966696c7465726c6f61640000210000002ef97a71170000000000000000000000000000000000000000000000060000000000000000",
+    "payload": "170000000000000000000000000000000000000000000000060000000000000000"
+  },
+  "FILTERADD": {
+    "message": "f9beb4d966696c7465726c6f61640000150000009727ea0a1499108ad8ed9bb6274d3980bab5a85c048f0950c8",
+    "payload": "1499108ad8ed9bb6274d3980bab5a85c048f0950c8"
+  },
+  "FILTERCLEAR": {
+    "message": "f9beb4d966696c7465726c6365617200000000005df6e0e2",
+    "payload": ""
   }
 }

test/messages.js

@@ -8,6 +8,7 @@ var Buffers = require('buffers');
 var bitcore = require('bitcore');
 var Data = require('./data/messages');
 var P2P = require('../');
+var BloomFilter = P2P.BloomFilter;
 var Messages = P2P.Messages;
 var Networks = bitcore.Networks;
 var BufferUtils = bitcore.util.buffer;
@@ -26,6 +27,9 @@ describe('Messages', function() {
     Alert: 'alert',
     Reject: 'reject',
     Block: 'block',
+    FilterLoad: 'filterload',
+    FilterAdd: 'filteradd',
+    FilterClear: 'filterclear',
     GetBlocks: 'getblocks',
     GetHeaders: 'getheaders',
     GetData: 'getdata',
@@ -34,7 +38,7 @@ describe('Messages', function() {
     Transaction: 'tx',
     NotFound: 'notfound'
   };
-  // TODO: add data for these 
+  // TODO: add data for these
   var noPayload = ['Reject', 'GetBlocks', 'GetHeaders'];
   var names = Object.keys(commands);
   describe('named', function() {
@@ -116,4 +120,10 @@ describe('Messages', function() {
 
   });
 
+  it('FilterLoad#fromBuffer method works', function() {
+    var testPayload = Data.FILTERLOAD.payload;
+    var msg = new Messages.FilterLoad().fromBuffer(new Buffer(testPayload, 'hex'));
+    msg.getPayload().toString('hex').should.equal(testPayload);
+  });
+
 });