public void Initialize()
{
if (false == Directory.Exists(LedgerPath))
{
Directory.CreateDirectory(LedgerPath);
}
Indexes.Initialize();
PhysicalBlock block = new PhysicalBlock();
block.Id = Indexes.GetNextBlockId();
block.LedgerId = Id;
block.TransactionData = System.Text.Encoding.ASCII.GetBytes("ledger initialized");
block.SignBlock = new SignBlock();
block.ComputeHash();
LedgerIndex index = Indexes.Add(block.Hash, block.TimeStamp);
if (block.Id != index.BlockID)
{
throw new LedgerException(Name, $"ID mismatch {block.Id}/{index.BlockID}");
}
// TODO: these next two steps are technically a transaction, need to determine what happens when
// one step fails.
System.Console.WriteLine($"saving indexes to {LedgerIndexFileName}");
Indexes.Save();
}
public void Initialize()
{
if (false == Directory.Exists(LedgerPath))
{
Directory.CreateDirectory(LedgerPath);
}
Indexes.Initialize();
PhysicalBlock block = new PhysicalBlock
{
Id = Indexes.GetNextBlockId(),
LedgerId = Id,
TransactionData = System.Text.Encoding.ASCII.GetBytes("ledger initialized"),
SignBlock = new SignBlock()
};
block.ComputeHash();
LedgerIndex index = Indexes.Add(block.Hash, block.TimeStamp);
if (block.Id != index.BlockId)
{
throw new LedgerException(Name, $"ID mismatch {block.Id}/{index.BlockId}");
}
// TODO: these next two steps are technically a transaction, need to determine what happens when
// one step fails.
_logger.LogInformation($"saving indexes to {LedgerIndexFileName}");
// step 1 save the block
// TODO: need rollback if Indexes.Save() fails
Writer.SaveBlock(block);
// step 2 save the index
Indexes.Save();
}
public void Load()
{
data.Clear();
string[] lines = File.ReadAllLines(IndexFile);
foreach (string line in lines)
{
data.Add(LedgerIndex.FromString(line));
}
isLoaded = true;
}
public void Validate()
{
State = LedgerState.StartingUp;
if (false == File.Exists(LedgerIndexFileName))
{
throw new LedgerNotFoundException(LedgerIndexFileName);
}
try
{
Indexes.Load();
// Validation Rule #1: the number of records in the index file should match
// the number of blocks saved on disk
if (Reader.CountBlocks() != Indexes.Count())
{
throw new LedgerNotValidException($"{Reader.CountBlocks()} != {Indexes.Count()}");
}
// Validation Rule #2: the boot record (which is the very first record)
// should be valid
PhysicalBlock rootBlock = Reader.GetLedgerPhysicalBlock(1, (data) => {
return(PhysicalBlock.FromString(data));
}) as PhysicalBlock;
LedgerIndex rootIndex = Indexes.GetIndex(1);
if (rootBlock.ComputeHash() != rootIndex.Hash)
{
throw new LedgerNotValidException($"block {rootBlock.Id}");
}
// Validation Rule #3: the last record should validate
// Validation Rule #4: verify a few other blocks
// TODO: validate some of the remaining blocks.
// TODO: have an option that requires all blocks to be validated
State = LedgerState.Available;
}
catch (Exception e)
{
State = LedgerState.Nonfunctional;
throw new LedgerException(Name, e);
}
}
public static LedgerIndex FromString(string data)
{
string[] elements = data.Split(":");
LedgerIndex index = new LedgerIndex();
index.BlockId = Convert.ToInt32(elements[0]);
index.Hash = elements[1];
DateTime expectedDate;
if (false == DateTime.TryParseExact(elements[2], Constants.DateTimeFormat, System.Globalization.CultureInfo.InvariantCulture, System.Globalization.DateTimeStyles.None, out expectedDate))
{
throw new LedgerNotValidException($"index is not valid");
}
index.Created = expectedDate;
return(index);
}
public LedgerIndex Add(string hash, DateTime created)
{
if (false == isLoaded)
{
throw new LedgerException(LedgerName, "Attempted to add index before loading");
}
LedgerIndex index = new LedgerIndex();
index.BlockId = GetNextBlockId();
index.Created = created;
index.Hash = hash;
data.Add(index);
return(index);
}
public int GetNextBlockId()
{
LedgerIndex mostrecent = data.OrderByDescending(u => u.BlockId).FirstOrDefault();
return((mostrecent == null ? 0 : mostrecent.BlockId) + 1);
}