private CoreDaemon CreateExampleDaemon(out BlockProvider embeddedBlocks, out IStorageManager storageManager, int? maxHeight = null)
{
// retrieve first 10,000 testnet3 blocks
embeddedBlocks = new BlockProvider("BitSharp.Examples.Blocks.TestNet3.zip");
// initialize in-memory storage
storageManager = new MemoryStorageManager();
// intialize testnet3 rules (ignore script errors, script engine is not and is not intended to be complete)
var chainParams = new Testnet3Params();
var rules = new CoreRules(chainParams) { IgnoreScriptErrors = true };
// initialize & start core daemon
var coreDaemon = new CoreDaemon(rules, storageManager) { MaxHeight = maxHeight, IsStarted = true };
// add embedded blocks
coreDaemon.CoreStorage.AddBlocks(embeddedBlocks.ReadBlocks());
// wait for core daemon to finish processing any available data
coreDaemon.WaitForUpdate();
return coreDaemon;
}
private void TestRollback(ITestStorageProvider provider)
{
ConsoleLoggingModule.Configure();
var logger = LogManager.GetCurrentClassLogger();
var blockCount = 10.THOUSAND();
var checkUtxoHashFrequencey = 1000;
var blockProvider = new TestNet3BlockProvider();
var blocks = blockProvider.ReadBlocks().Take(blockCount).ToList();
var genesisBlock = blocks[0];
var genesisHeader = new ChainedHeader(genesisBlock.Header, height: 0, totalWork: 0, dateSeen: DateTimeOffset.Now);
var genesisChain = Chain.CreateForGenesisBlock(genesisHeader);
var chainParams = new Testnet3Params();
var rules = new CoreRules(chainParams)
{
IgnoreScripts = true,
IgnoreSignatures = true,
IgnoreScriptErrors = true
};
using (var storageManager = provider.OpenStorageManager())
using (var coreStorage = new CoreStorage(storageManager))
using (var chainStateBuilder = new ChainStateBuilder(rules, coreStorage, storageManager))
{
// add blocks to storage
coreStorage.AddGenesisBlock(ChainedHeader.CreateForGenesisBlock(blocks[0].Header));
foreach (var block in blocks)
coreStorage.TryAddBlock(block);
// store empty utxo hash
var expectedUtxoHashes = new List<UInt256>();
using (var chainState = chainStateBuilder.ToImmutable())
expectedUtxoHashes.Add(UtxoCommitment.ComputeHash(chainState));
// calculate utxo forward and store its state at each step along the way
for (var blockIndex = 0; blockIndex < blocks.Count; blockIndex++)
{
logger.Info($"Adding: {blockIndex:N0}");
var block = blocks[blockIndex];
var chainedHeader = new ChainedHeader(block.Header, blockIndex, 0, DateTimeOffset.Now);
chainStateBuilder.AddBlockAsync(chainedHeader, block.Transactions.Select(
(tx, txIndex) => BlockTx.Create(txIndex, tx))).Wait();
if (blockIndex % checkUtxoHashFrequencey == 0 || blockIndex == blocks.Count - 1)
using (var chainState = chainStateBuilder.ToImmutable())
expectedUtxoHashes.Add(UtxoCommitment.ComputeHash(chainState));
}
// verify the utxo state before rolling back
var expectedLastUtxoHash = UInt256.ParseHex("5f155c7d8a5c850d5fb2566aec5110caa40e270184126d17022ae9780fd65fd9");
Assert.AreEqual(expectedLastUtxoHash, expectedUtxoHashes.Last());
expectedUtxoHashes.RemoveAt(expectedUtxoHashes.Count - 1);
// roll utxo backwards and validate its state at each step along the way
for (var blockIndex = blocks.Count - 1; blockIndex >= 0; blockIndex--)
{
logger.Info($"Rolling back: {blockIndex:N0}");
var block = blocks[blockIndex];
var chainedHeader = new ChainedHeader(block.Header, blockIndex, 0, DateTimeOffset.Now);
var blockTxes = block.Transactions.Select((tx, txIndex) => BlockTx.Create(txIndex, tx));
chainStateBuilder.RollbackBlock(chainedHeader, blockTxes);
if ((blockIndex - 1) % checkUtxoHashFrequencey == 0 || blockIndex == 0)
{
var expectedUtxoHash = expectedUtxoHashes.Last();
expectedUtxoHashes.RemoveAt(expectedUtxoHashes.Count - 1);
using (var chainState = chainStateBuilder.ToImmutable())
Assert.AreEqual(expectedUtxoHash, UtxoCommitment.ComputeHash(chainState));
}
}
// verify chain state was rolled all the way back
Assert.AreEqual(-1, chainStateBuilder.Chain.Height);
Assert.AreEqual(0, expectedUtxoHashes.Count);
// calculate utxo forward again
for (var blockIndex = 0; blockIndex < blocks.Count; blockIndex++)
{
logger.Info($"Adding: {blockIndex:N0}");
var block = blocks[blockIndex];
var chainedHeader = new ChainedHeader(block.Header, blockIndex, 0, DateTimeOffset.Now);
chainStateBuilder.AddBlockAsync(chainedHeader, block.Transactions.Select(
(tx, txIndex) => BlockTx.Create(txIndex, tx))).Wait();
}
// verify final utxo state again
using (var chainState = chainStateBuilder.ToImmutable())
Assert.AreEqual(expectedLastUtxoHash, UtxoCommitment.ComputeHash(chainState));
}
}