/// <summary>
/// Executes the <paramref name="actions"/> step by step, and emits
/// <see cref="ActionEvaluation"/> for each step.
/// </summary>
/// <param name="blockHash">The <see cref="Block{T}.Hash"/> of <see cref="Block{T}"/> that
/// <paramref name="actions"/> belongs to.</param>
/// <param name="blockIndex">The <see cref="Block{T}.Index"/> of <see cref="Block{T}"/> that
/// <paramref name="actions"/> belongs to.</param>
/// <param name="txid">The <see cref="Transaction{T}.Id"/> of <see cref="Transaction{T}"/>
/// that <paramref name="actions"/> belongs to. This can be <c>null</c> on rehearsal mode
/// or if an action is a <see cref="IBlockPolicy{T}.BlockAction"/>.</param>
/// <param name="previousStates">The states immediately before <paramref name="actions"/>
/// being executed. Note that its <see cref="IAccountStateDelta.UpdatedAddresses"/> are
/// remained to the returned next states.</param>
/// <param name="minerAddress">An address of block miner.</param>
/// <param name="signer">Signer of the <paramref name="actions"/>.</param>
/// <param name="signature"><see cref="Transaction{T}"/> signature used to generate random
/// seeds.</param>
/// <param name="actions">Actions to evaluate.</param>
/// <param name="rehearsal">Pass <c>true</c> if it is intended
/// to be dry-run (i.e., the returned result will be never used).
/// The default value is <c>false</c>.</param>
/// <param name="previousBlockStatesTrie">The trie to contain states at previous block.
/// </param>
/// <param name="blockAction">Pass <c>true</c> if it is
/// <see cref="IBlockPolicy{T}.BlockAction"/>.</param>
/// <returns>Enumerates <see cref="ActionEvaluation"/>s for each one in
/// <paramref name="actions"/>. The order is the same to the <paramref name="actions"/>.
/// Note that each <see cref="IActionContext.Random"/> object
/// has a unconsumed state.
/// </returns>
internal static IEnumerable <ActionEvaluation> EvaluateActionsGradually(
HashDigest <SHA256> blockHash,
long blockIndex,
TxId?txid,
IAccountStateDelta previousStates,
Address minerAddress,
Address signer,
byte[] signature,
IImmutableList <IAction> actions,
bool rehearsal = false,
ITrie previousBlockStatesTrie = null,
bool blockAction = false)
{
ActionContext CreateActionContext(
IAccountStateDelta prevStates,
int randomSeed
) =>
new ActionContext(
signer: signer,
miner: minerAddress,
blockIndex: blockIndex,
previousStates: prevStates,
randomSeed: randomSeed,
rehearsal: rehearsal,
previousBlockStatesTrie: previousBlockStatesTrie,
blockAction: blockAction
);
byte[] hashedSignature;
using (var hasher = SHA1.Create())
{
hashedSignature = hasher.ComputeHash(signature);
}
int seed =
BitConverter.ToInt32(blockHash.ToByteArray(), 0) ^
(signature.Any() ? BitConverter.ToInt32(hashedSignature, 0) : 0);
IAccountStateDelta states = previousStates;
Exception exc = null;
foreach (IAction action in actions)
{
ActionContext context = CreateActionContext(states, seed);
IAccountStateDelta nextStates = context.PreviousStates;
try
{
DateTimeOffset actionExecutionStarted = DateTimeOffset.Now;
nextStates = action.Execute(context);
TimeSpan spent = DateTimeOffset.Now - actionExecutionStarted;
Log.Verbose($"{action} execution spent {spent.TotalMilliseconds} ms.");
}
catch (Exception e)
{
if (rehearsal)
{
var msg =
$"The action {action} threw an exception during its " +
"rehearsal. It is probably because the logic of the " +
$"action {action} is not enough generic so that it " +
"can cover every case including rehearsal mode.\n" +
"The IActionContext.Rehearsal property also might be " +
"useful to make the action can deal with the case of " +
"rehearsal mode.\n" +
"See also this exception's InnerException property.";
exc = new UnexpectedlyTerminatedActionException(
null, null, null, null, action, msg, e
);
}
else
{
var stateRootHash = context.PreviousStateRootHash;
var msg =
$"The action {action} (block #{blockIndex} {blockHash}, tx {txid}, " +
$"state root hash {stateRootHash}) threw an exception " +
"during execution. See also this exception's InnerException property.";
Log.Error("{Message}\nInnerException: {ExcMessage}", msg, e.Message);
exc = new UnexpectedlyTerminatedActionException(
blockHash, blockIndex, txid, stateRootHash, action, msg, e
);
}
}
// As IActionContext.Random is stateful, we cannot reuse
// the context which is once consumed by Execute().
ActionContext equivalentContext = CreateActionContext(states, seed);
yield return(new ActionEvaluation(
action,
equivalentContext,
nextStates,
exc
));
states = nextStates;
unchecked
{
seed++;
}
}
}
/// <summary>
/// Executes the <paramref name="actions"/> step by step, and emits
/// <see cref="ActionEvaluation"/> for each step.
/// </summary>
/// <param name="blockHash">The <see cref="Block{T}.Hash"/> of <see cref="Block{T}"/> that
/// <paramref name="actions"/> belongs to.</param>
/// <param name="blockIndex">The <see cref="Block{T}.Index"/> of <see cref="Block{T}"/> that
/// <paramref name="actions"/> belongs to.</param>
/// <param name="txid">The <see cref="Transaction{T}.Id"/> of <see cref="Transaction{T}"/>
/// that <paramref name="actions"/> belongs to. This can be <c>null</c> on rehearsal mode
/// or if an action is a <see cref="IBlockPolicy{T}.BlockAction"/>.</param>
/// <param name="previousStates">The states immediately before <paramref name="actions"/>
/// being executed. Note that its <see cref="IAccountStateDelta.UpdatedAddresses"/> are
/// remained to the returned next states.</param>
/// <param name="minerAddress">An address of block miner.</param>
/// <param name="signer">Signer of the <paramref name="actions"/>.</param>
/// <param name="signature"><see cref="Transaction{T}"/> signature used to generate random
/// seeds.</param>
/// <param name="actions">Actions to evaluate.</param>
/// <param name="rehearsal">Pass <c>true</c> if it is intended
/// to be dry-run (i.e., the returned result will be never used).
/// The default value is <c>false</c>.</param>
/// <returns>Enumerates <see cref="ActionEvaluation"/>s for each one in
/// <paramref name="actions"/>. The order is the same to the <paramref name="actions"/>.
/// Note that each <see cref="IActionContext.Random"/> object
/// has a unconsumed state.
/// </returns>
internal static IEnumerable <ActionEvaluation> EvaluateActionsGradually(
HashDigest <SHA256> blockHash,
long blockIndex,
TxId?txid,
IAccountStateDelta previousStates,
Address minerAddress,
Address signer,
byte[] signature,
IImmutableList <IAction> actions,
bool rehearsal = false)
{
ActionContext CreateActionContext(
IAccountStateDelta prevStates,
int randomSeed
) =>
new ActionContext(
signer: signer,
miner: minerAddress,
blockIndex: blockIndex,
previousStates: prevStates,
randomSeed: randomSeed,
rehearsal: rehearsal
);
byte[] hashedSignature;
using (var hasher = SHA1.Create())
{
hashedSignature = hasher.ComputeHash(signature);
}
int seed =
BitConverter.ToInt32(blockHash.ToByteArray(), 0) ^
(signature.Any() ? BitConverter.ToInt32(hashedSignature, 0) : 0);
IAccountStateDelta states = previousStates;
Exception exc = null;
foreach (IAction action in actions)
{
ActionContext context = CreateActionContext(states, seed);
IAccountStateDelta nextStates = context.PreviousStates;
try
{
nextStates = action.Execute(context);
}
catch (Exception e)
{
string msg;
if (!rehearsal)
{
// FIXME: The below "exc" object seems never used; Hong Minhee believes
// this code's behavior does not follow the intention.
msg = $"The action {action} (block #{blockIndex} {blockHash}, tx {txid}) " +
"threw an exception during execution. See also this exception's " +
"InnerException property.";
exc = new UnexpectedlyTerminatedActionException(
blockHash, blockIndex, txid, action, msg, e
);
}
msg =
$"The action {action} threw an exception during its " +
"rehearsal. It is probably because the logic of the " +
$"action {action} is not enough generic so that it " +
"can cover every case including rehearsal mode.\n" +
"The IActionContext.Rehearsal property also might be " +
"useful to make the action can deal with the case of " +
"rehearsal mode.\n" +
"See also this exception's InnerException property.";
exc = new UnexpectedlyTerminatedActionException(
null, null, null, action, msg, e
);
}
// As IActionContext.Random is stateful, we cannot reuse
// the context which is once consumed by Execute().
ActionContext equivalentContext = CreateActionContext(states, seed);
yield return(new ActionEvaluation(
action,
equivalentContext,
nextStates,
exc
));
states = nextStates;
unchecked
{
seed++;
}
}
}
