@Test
public void testProofOfWork() throws Exception {
// This params accepts any difficulty target.
NetworkParameters params = UnitTestParams.get();
Block block = params.getDefaultSerializer().makeBlock(blockBytes);
block.setNonce(12346);
try {
block.verify(Block.BLOCK_HEIGHT_GENESIS, EnumSet.noneOf(Block.VerifyFlag.class));
fail();
} catch (VerificationException e) {
// Expected.
}
// Blocks contain their own difficulty target. The BlockChain verification mechanism is what
// stops real blocks
// from containing artificially weak difficulties.
block.setDifficultyTarget(Block.EASIEST_DIFFICULTY_TARGET);
// Now it should pass.
block.verify(Block.BLOCK_HEIGHT_GENESIS, EnumSet.noneOf(Block.VerifyFlag.class));
// Break the nonce again at the lower difficulty level so we can try solving for it.
block.setNonce(1);
try {
block.verify(Block.BLOCK_HEIGHT_GENESIS, EnumSet.noneOf(Block.VerifyFlag.class));
fail();
} catch (VerificationException e) {
// Expected to fail as the nonce is no longer correct.
}
// Should find an acceptable nonce.
block.solve();
block.verify(Block.BLOCK_HEIGHT_GENESIS, EnumSet.noneOf(Block.VerifyFlag.class));
assertEquals(block.getNonce(), 2);
}
public void testBlock(byte[] blockBytes, boolean isChild, boolean lazy, boolean retain)
throws Exception {
// reference serializer to produce comparison serialization output after changes to
// message structure.
BitcoinSerializer bsRef = new BitcoinSerializer(unitTestParams, false, false);
ByteArrayOutputStream bos = new ByteArrayOutputStream();
BitcoinSerializer bs = new BitcoinSerializer(unitTestParams, lazy, retain);
Block b1;
Block bRef;
b1 = (Block) bs.deserialize(new ByteArrayInputStream(blockBytes));
bRef = (Block) bsRef.deserialize(new ByteArrayInputStream(blockBytes));
// verify our reference BitcoinSerializer produces matching byte array.
bos.reset();
bsRef.serialize(bRef, bos);
assertTrue(Arrays.equals(bos.toByteArray(), blockBytes));
// check lazy and retain status survive both before and after a serialization
assertEquals(!lazy, b1.isParsedTransactions());
assertEquals(!lazy, b1.isParsedHeader());
if (b1.isParsedHeader()) assertEquals(retain, b1.isHeaderBytesValid());
if (b1.isParsedTransactions()) assertEquals(retain, b1.isTransactionBytesValid());
serDeser(bs, b1, blockBytes, null, null);
assertEquals(!lazy, b1.isParsedTransactions());
assertEquals(!lazy, b1.isParsedHeader());
if (b1.isParsedHeader()) assertEquals(retain, b1.isHeaderBytesValid());
if (b1.isParsedTransactions()) assertEquals(retain, b1.isTransactionBytesValid());
// compare to ref block
bos.reset();
bsRef.serialize(bRef, bos);
serDeser(bs, b1, bos.toByteArray(), null, null);
// retrieve a value from a child
b1.getTransactions();
assertTrue(b1.isParsedTransactions());
if (b1.getTransactions().size() > 0) {
assertTrue(b1.isParsedTransactions());
Transaction tx1 = b1.getTransactions().get(0);
// this will always be true for all children of a block once they are retrieved.
// the tx child inputs/outputs may not be parsed however.
// no longer forced to parse if length not provided.
// assertEquals(true, tx1.isParsed());
if (tx1.isParsed()) assertEquals(retain, tx1.isCached());
else assertTrue(tx1.isCached());
// does it still match ref block?
serDeser(bs, b1, bos.toByteArray(), null, null);
}
// refresh block
b1 = (Block) bs.deserialize(new ByteArrayInputStream(blockBytes));
bRef = (Block) bsRef.deserialize(new ByteArrayInputStream(blockBytes));
// retrieve a value from header
b1.getDifficultyTarget();
assertTrue(b1.isParsedHeader());
assertEquals(lazy, !b1.isParsedTransactions());
// does it still match ref block?
serDeser(bs, b1, bos.toByteArray(), null, null);
// refresh block
b1 = (Block) bs.deserialize(new ByteArrayInputStream(blockBytes));
bRef = (Block) bsRef.deserialize(new ByteArrayInputStream(blockBytes));
// retrieve a value from a child and header
b1.getDifficultyTarget();
assertTrue(b1.isParsedHeader());
assertEquals(lazy, !b1.isParsedTransactions());
b1.getTransactions();
assertTrue(b1.isParsedTransactions());
if (b1.getTransactions().size() > 0) {
assertTrue(b1.isParsedTransactions());
Transaction tx1 = b1.getTransactions().get(0);
// no longer forced to parse if length not provided.
// assertEquals(true, tx1.isParsed());
if (tx1.isParsed()) assertEquals(retain, tx1.isCached());
else assertTrue(tx1.isCached());
}
// does it still match ref block?
serDeser(bs, b1, bos.toByteArray(), null, null);
// refresh block
b1 = (Block) bs.deserialize(new ByteArrayInputStream(blockBytes));
bRef = (Block) bsRef.deserialize(new ByteArrayInputStream(blockBytes));
// change a value in header
b1.setNonce(23);
bRef.setNonce(23);
assertTrue(b1.isParsedHeader());
assertEquals(lazy, !b1.isParsedTransactions());
assertFalse(b1.isHeaderBytesValid());
if (b1.isParsedTransactions()) assertEquals(retain, b1.isTransactionBytesValid());
else assertEquals(true, b1.isTransactionBytesValid());
// does it still match ref block?
bos.reset();
bsRef.serialize(bRef, bos);
serDeser(bs, b1, bos.toByteArray(), null, null);
// refresh block
b1 = (Block) bs.deserialize(new ByteArrayInputStream(blockBytes));
bRef = (Block) bsRef.deserialize(new ByteArrayInputStream(blockBytes));
// retrieve a value from a child of a child
b1.getTransactions();
if (b1.getTransactions().size() > 0) {
Transaction tx1 = b1.getTransactions().get(0);
TransactionInput tin = tx1.getInputs().get(0);
assertTrue(tx1.isParsed());
assertTrue(b1.isParsedTransactions());
assertEquals(!lazy, b1.isParsedHeader());
assertEquals(!lazy, tin.isParsed());
assertEquals(tin.isParsed() ? retain : true, tin.isCached());
// does it still match ref tx?
bos.reset();
bsRef.serialize(bRef, bos);
serDeser(bs, b1, bos.toByteArray(), null, null);
}
// refresh block
b1 = (Block) bs.deserialize(new ByteArrayInputStream(blockBytes));
bRef = (Block) bsRef.deserialize(new ByteArrayInputStream(blockBytes));
// add an input
b1.getTransactions();
if (b1.getTransactions().size() > 0) {
Transaction tx1 = b1.getTransactions().get(0);
if (tx1.getInputs().size() > 0) {
tx1.addInput(tx1.getInputs().get(0));
// replicate on reference tx
bRef.getTransactions().get(0).addInput(bRef.getTransactions().get(0).getInputs().get(0));
assertFalse(tx1.isCached());
assertTrue(tx1.isParsed());
assertFalse(b1.isTransactionBytesValid());
assertTrue(b1.isParsedHeader());
// confirm sibling cache status was unaffected
if (tx1.getInputs().size() > 1) {
boolean parsed = tx1.getInputs().get(1).isParsed();
assertEquals(parsed ? retain : true, tx1.getInputs().get(1).isCached());
assertEquals(!lazy, parsed);
}
// this has to be false. Altering a tx invalidates the merkle root.
// when we have seperate merkle caching then the entire header won't need to be
// invalidated.
assertFalse(b1.isHeaderBytesValid());
bos.reset();
bsRef.serialize(bRef, bos);
byte[] source = bos.toByteArray();
// confirm we still match the reference tx.
serDeser(bs, b1, source, null, null);
}
// does it still match ref tx?
bos.reset();
bsRef.serialize(bRef, bos);
serDeser(bs, b1, bos.toByteArray(), null, null);
}
// refresh block
b1 = (Block) bs.deserialize(new ByteArrayInputStream(blockBytes));
Block b2 = (Block) bs.deserialize(new ByteArrayInputStream(blockBytes));
bRef = (Block) bsRef.deserialize(new ByteArrayInputStream(blockBytes));
Block bRef2 = (Block) bsRef.deserialize(new ByteArrayInputStream(blockBytes));
// reparent an input
b1.getTransactions();
if (b1.getTransactions().size() > 0) {
Transaction tx1 = b1.getTransactions().get(0);
Transaction tx2 = b2.getTransactions().get(0);
if (tx1.getInputs().size() > 0) {
TransactionInput fromTx1 = tx1.getInputs().get(0);
tx2.addInput(fromTx1);
// replicate on reference tx
TransactionInput fromTxRef = bRef.getTransactions().get(0).getInputs().get(0);
bRef2.getTransactions().get(0).addInput(fromTxRef);
// b1 hasn't changed but it's no longer in the parent
// chain of fromTx1 so has to have been uncached since it won't be
// notified of changes throught the parent chain anymore.
assertFalse(b1.isTransactionBytesValid());
// b2 should have it's cache invalidated because it has changed.
assertFalse(b2.isTransactionBytesValid());
bos.reset();
bsRef.serialize(bRef2, bos);
byte[] source = bos.toByteArray();
// confirm altered block matches altered ref block.
serDeser(bs, b2, source, null, null);
}
// does unaltered block still match ref block?
bos.reset();
bsRef.serialize(bRef, bos);
serDeser(bs, b1, bos.toByteArray(), null, null);
// how about if we refresh it?
bRef = (Block) bsRef.deserialize(new ByteArrayInputStream(blockBytes));
bos.reset();
bsRef.serialize(bRef, bos);
serDeser(bs, b1, bos.toByteArray(), null, null);
}
}