public void OnBlock(IStore store, BeaconBlock block)
{
// Make a copy of the state to avoid mutability issues
if (!store.TryGetBlockState(block.ParentRoot, out var parentState))
{
throw new ArgumentOutOfRangeException(nameof(block), block.ParentRoot, "Block parent root not found in the block states history.");
}
var preState = BeaconState.Clone(parentState);
// Blocks cannot be in the future. If they are, their consideration must be delayed until the are in the past.
var blockTime = preState.GenesisTime + (ulong)block.Slot * _timeParameterOptions.CurrentValue.SecondsPerSlot;
if (blockTime > store.Time)
{
throw new ArgumentOutOfRangeException(nameof(block), blockTime, $"Block slot time cannot be in the future, compared to store time {store.Time}.");
}
// Add new block to the store
var signingRoot = block.SigningRoot(_miscellaneousParameterOptions.CurrentValue, _maxOperationsPerBlockOptions.CurrentValue);
store.AddBlock(signingRoot, block);
// Check block is a descendant of the finalized block
if (!store.TryGetBlock(store.FinalizedCheckpoint.Root, out var finalizedCheckpointBlock))
{
throw new Exception($"Block not found for finalized checkpoint root {store.FinalizedCheckpoint.Root}.");
}
var ancestor = GetAncestor(store, signingRoot, finalizedCheckpointBlock.Slot);
if (ancestor != store.FinalizedCheckpoint.Root)
{
throw new Exception($"Block with signing root {signingRoot} is not a descendant of the finalized block {store.FinalizedCheckpoint.Root} at slot {finalizedCheckpointBlock.Slot}.");
}
// Check that block is later than the finalized epoch slot
var finalizedEpochStartSlot = _beaconChainUtility.ComputeStartSlotOfEpoch(store.FinalizedCheckpoint.Epoch);
if (block.Slot <= finalizedEpochStartSlot)
{
throw new ArgumentOutOfRangeException(nameof(block), block.Slot, $"Block slot must be later than the finalized epoch start slot {finalizedEpochStartSlot}.");
}
// Check the block is valid and compute the post-state
var state = _beaconStateTransition.StateTransition(preState, block, validateStateRoot: true);
// Add new state for this block to the store
store.AddBlockState(signingRoot, state);
_logger.LogInformation(Event.CreateGenesisStore, "Store added block {BeaconBlock} generating state {BeaconState}, with signing root {SigningRoot}",
block, state, signingRoot);
// Update justified checkpoint
if (state.CurrentJustifiedCheckpoint.Epoch > store.JustifiedCheckpoint.Epoch)
{
store.SetBestJustifiedCheckpoint(state.CurrentJustifiedCheckpoint);
var shouldUpdateJustifiedCheckpoint = ShouldUpdateJustifiedCheckpoint(store, state.CurrentJustifiedCheckpoint);
if (shouldUpdateJustifiedCheckpoint)
{
store.SetJustifiedCheckpoint(state.CurrentJustifiedCheckpoint);
_logger.LogDebug("Updated justified checkpoint {JustifiedCheckpoint}", state.CurrentJustifiedCheckpoint);
}
else
{
_logger.LogDebug("Updated best justified checkpoint {JustifiedCheckpoint}", state.CurrentJustifiedCheckpoint);
}
}
// Update finalized checkpoint
if (state.FinalizedCheckpoint.Epoch > store.FinalizedCheckpoint.Epoch)
{
store.SetFinalizedCheckpoint(state.FinalizedCheckpoint);
_logger.LogDebug("Updated finalized checkpoint {FinalizedCheckpoint}", state.FinalizedCheckpoint);
}
}