block serialization: Add option skip magic numbers

10 years ago · b416655222
4 changed files with 54 additions and 60 deletions
--- a/lib/block.js
+++ b/lib/block.js
@ -59,12 +59,11 @@ Block._from = function _from(arg) {
       * @type {BlockHeader}
       */
      header: arg.header,
-      txsvi: arg.txsvi,
      /**
-       * @name Block#txs
+       * @name Block#transactions
       * @type {Transaction[]}
       */
-      txs: arg.txs
+      transactions: arg.transactions
    };
  } else {
    throw new TypeError('Unrecognized argument for Block');
@ -81,16 +80,15 @@ Block._fromJSON = function _fromJSON(data) {
  if (JSUtil.isValidJSON(data)) {
    data = JSON.parse(data);
  }
-  var txs = [];
-  data.txs.forEach(function(tx) {
-    txs.push(Transaction().fromJSON(tx));
+  var transactions = [];
+  data.transactions.forEach(function(data) {
+    transactions.push(Transaction().fromJSON(data));
  });
  var info = {
    magicnum: data.magicnum,
    size: data.size,
    header: BlockHeader.fromJSON(data.header),
-    txsvi: Varint().fromString(data.txsvi),
-    txs: txs
+    transactions: transactions
  };
  return info;
 };
@ -109,16 +107,22 @@ Block.fromJSON = function fromJSON(json) {
 * @returns {Object} - An object representing the block data
 * @private
 */
-Block._fromBufferReader = function _fromBufferReader(br) {
+Block._fromBufferReader = function _fromBufferReader(br, options) {
+  options = options || {};
  var info = {};
-  info.magicnum = br.readUInt32LE();
-  info.size = br.readUInt32LE();
+  if (!options.skipMagic) {
+    info.magicnum = br.readUInt32LE();
+    info.size = br.readUInt32LE();
+  }
  info.header = BlockHeader.fromBufferReader(br);
-  info.txsvi = Varint(br.readVarintBuf());
-  var txslen = info.txsvi.toNumber();
-  info.txs = [];
-  for (var i = 0; i < txslen; i++) {
-    info.txs.push(Transaction().fromBufferReader(br));
+  if (options.skipMagic) {
+    info.magicnum = 0;
+    info.size = info.header.bits;
+  }
+  var transactions = br.readVarintNum();
+  info.transactions = [];
+  for (var i = 0; i < transactions; i++) {
+    info.transactions.push(Transaction().fromBufferReader(br));
  }
  return info;
 };
@ -127,8 +131,8 @@ Block._fromBufferReader = function _fromBufferReader(br) {
 * @param {BufferReader} - A buffer reader of the block
 * @returns {Block} - An instance of block
 */
-Block.fromBufferReader = function fromBufferReader(br) {
-  var info = Block._fromBufferReader(br);
+Block.fromBufferReader = function fromBufferReader(br, opts) {
+  var info = Block._fromBufferReader(br, opts);
  return new Block(info);
 };

@ -136,8 +140,8 @@ Block.fromBufferReader = function fromBufferReader(br) {
 * @param {Buffer} - A buffer of the block
 * @returns {Block} - An instance of block
 */
-Block.fromBuffer = function fromBuffer(buf) {
-  return Block.fromBufferReader(BufferReader(buf));
+Block.fromBuffer = function fromBuffer(buf, opts) {
+  return Block.fromBufferReader(BufferReader(buf), opts);
 };

 /**
@ -166,16 +170,15 @@ Block.fromRawBlock = function fromRawBlock(data) {
 * @returns {Object} - A plain object with the block properties
 */
 Block.prototype.toObject = function toObject() {
-  var txs = [];
-  this.txs.forEach(function(tx) {
-    txs.push(tx.toObject());
+  var transactions = [];
+  this.transactions.forEach(function(tx) {
+    transactions.push(tx.toObject());
  });
  return {
    magicnum: this.magicnum,
    size: this.size,
    header: this.header.toObject(),
-    txsvi: this.txsvi.toString(),
-    txs: txs
+    transactions: transactions
  };
 };

@ -211,10 +214,9 @@ Block.prototype.toBufferWriter = function toBufferWriter(bw) {
  bw.writeUInt32LE(this.magicnum);
  bw.writeUInt32LE(this.size);
  bw.write(this.header.toBuffer());
-  bw.write(this.txsvi.buf);
-  var txslen = this.txsvi.toNumber();
-  for (var i = 0; i < txslen; i++) {
-    this.txs[i].toBufferWriter(bw);
+  bw.writeVarintNum(this.transactions.length);
+  for (var i = 0; i < this.transactions.length; i++) {
+    this.transactions[i].toBufferWriter(bw);
  }
  return bw;
 };
@ -225,11 +227,11 @@ Block.prototype.toBufferWriter = function toBufferWriter(bw) {
 */
 Block.prototype.getTransactionHashes = function getTransactionHashes() {
  var hashes = [];
-  if (this.txs.length === 0) {
+  if (this.transactions.length === 0) {
    return [Block.Values.NULL_HASH];
  }
-  for (var t = 0; t < this.txs.length; t++) {
-    hashes.push(this.txs[t]._getHash());
+  for (var t = 0; t < this.transactions.length; t++) {
+    hashes.push(this.transactions[t]._getHash());
  }
  return hashes;
 };
@ -245,7 +247,7 @@ Block.prototype.getMerkleTree = function getMerkleTree() {
  var tree = this.getTransactionHashes();

  var j = 0;
-  for (var size = this.txs.length; size > 1; size = Math.floor((size + 1) / 2)) {
+  for (var size = this.transactions.length; size > 1; size = Math.floor((size + 1) / 2)) {
    for (var i = 0; i < size; i += 2) {
      var i2 = Math.min(i + 1, size - 1);
      var buf = Buffer.concat([tree[j + i], tree[j + i2]]);
--- a/lib/blockheader.js
+++ b/lib/blockheader.js
@ -119,14 +119,13 @@ BlockHeader.fromString = function fromString(str) {
 * @private
 */
 BlockHeader._fromBufferReader = function _fromBufferReader(br) {
-  var info = {
-    version: br.readUInt32LE(),
-    prevHash: br.read(32),
-    merkleRoot: br.read(32),
-    time: br.readUInt32LE(),
-    bits: br.readUInt32LE(),
-    nonce: br.readUInt32LE()
-  };
+  var info = {};
+  info.version = br.readUInt32LE();
+  info.prevHash = br.read(32);
+  info.merkleRoot = br.read(32);
+  info.time = br.readUInt32LE();
+  info.bits = br.readUInt32LE();
+  info.nonce = br.readUInt32LE();
  return info;
 };

--- a/test/block.js
+++ b/test/block.js
@ -27,9 +27,8 @@ describe('Block', function() {
  var blockbuf = new Buffer(blockhex, 'hex');
  var size = data.blocksize;
  var bh = BlockHeader.fromBuffer(new Buffer(data.blockheaderhex, 'hex'));
-  var txsvi = Varint().fromNumber(data.txsvi);
  var txs = [];
-  JSON.parse(dataJson).txs.forEach(function(tx){
+  JSON.parse(dataJson).transactions.forEach(function(tx){
    txs.push(new Transaction().fromJSON(tx));
  });
  var json = dataJson;
@ -45,7 +44,7 @@ describe('Block', function() {

  it('should not make an empty block', function() {
    (function() {
-      var b = new Block();
+      return new Block();
    }).should.throw('Unrecognized argument for Block');
  });

@ -56,20 +55,18 @@ describe('Block', function() {
        magicnum: magicnum,
        size: size,
        header: bh,
-        txsvi: txsvi,
-        txs: txs
+        transactions: txs
      });
      should.exist(b.magicnum);
      should.exist(b.size);
-      should.exist(b.txsvi);
      should.exist(b.header);
-      should.exist(b.txs);
+      should.exist(b.transactions);
    });

    it('should properly deserialize blocks', function() {
      dataBlocks.forEach(function(block){
-        var b = Block.fromBuffer(new Buffer(block.data, 'hex'));
-        b.txs.length.should.equal(block.transactions);
+        var b = Block.fromBuffer(new Buffer(block.data, 'hex'), {skipMagic: true});
+        b.transactions.length.should.equal(block.transactions);
      });
    });

@ -98,8 +95,7 @@ describe('Block', function() {
      should.exist(block.magicnum);
      should.exist(block.size);
      should.exist(block.header);
-      should.exist(block.txsvi);
-      should.exist(block.txs);
+      should.exist(block.transactions);
    });

    it('should set these known values', function() {
@ -108,8 +104,7 @@ describe('Block', function() {
      should.exist(block.magicnum);
      should.exist(block.size);
      should.exist(block.header);
-      should.exist(block.txsvi);
-      should.exist(block.txs);
+      should.exist(block.transactions);
    });

    it('accepts an object as argument', function() {
@ -127,8 +122,7 @@ describe('Block', function() {
      should.exist(b.magicnum);
      should.exist(b.size);
      should.exist(b.header);
-      should.exist(b.txsvi);
-      should.exist(b.txs);
+      should.exist(b.transactions);
    });

  });
@ -225,14 +219,14 @@ describe('Block', function() {

    it('should describe as invalid merkle root', function() {
      var x = Block.fromRawBlock(dataRawBlockBinary);
-      x.txs.push(new Transaction());
+      x.transactions.push(new Transaction());
      var valid = x.validMerkleRoot();
      valid.should.equal(false);
    });

    it('should get a null hash merkle root', function() {
      var x = Block.fromRawBlock(dataRawBlockBinary);
-      x.txs = []; // empty the txs
+      x.transactions = []; // empty the txs
      var mr = x.getMerkleRoot();
      mr.should.deep.equal(Block.Values.NULL_HASH);
    });
--- a/test/data/blk86756-testnet.json
+++ b/test/data/blk86756-testnet.json
@ -9,8 +9,7 @@
    "bits": 473956288,
    "nonce": 3594009557
  },
-  "txsvi": "16",
-  "txs": [{
+  "transactions": [{
    "version": 1,
    "txinsvi": "01",
    "txins": [{