public void TruncatingLogSetsCommitAndApplyIndexToIndexToTruncateFrom()
{
// Arrange
var eventDispatcher = Substitute.For <IEventDispatcher>();
var raftNode = new Node(eventDispatcher)
{
Data =
{
CommitIndex = 10,
LastApplied = 10
}
};
var cmd = new TruncateLog
{
TruncateFromIndex = raftNode.Data.CommitIndex - 5
};
TransitionNodeFromInitialState(raftNode, NodeState.Follower);
raftNode.FireAtStateMachine <TruncateLog>();
// Act
raftNode.Handle(cmd);
// Assert
raftNode.Data.CommitIndex.Should().Be(cmd.TruncateFromIndex);
raftNode.Data.LastApplied.Should().Be(cmd.TruncateFromIndex);
}
public void Handle(TruncateLog @event)
{
if (@event.TruncateFromIndex > Data.CommitIndex)
{
throw new InvalidOperationException("Cannot truncate from the specified index as it is greater than the nodes current commit index.");
}
Data.CommitIndex = @event.TruncateFromIndex;
Data.LastApplied = @event.TruncateFromIndex;
Data.Log.TruncateLog(@event.TruncateFromIndex);
}
public void TruncatingCallsTruncateLogOnNodeLog()
{
// Arrange
const long logTerm = 34;
const long initialIdx = 10;
const long truncateFromIdx = initialIdx / 2;
var eventDispatcher = Substitute.For <IEventDispatcher>();
var raftNode = new Node(eventDispatcher)
{
Data =
{
CommitIndex = initialIdx,
CurrentTerm = logTerm
}
};
for (var i = 0; i < initialIdx; i++)
{
raftNode.Data.Log.SetLogEntry(i + 1, logTerm);
}
raftNode.Data.Log[truncateFromIdx].Should().Be(logTerm);
raftNode.Data.Log[truncateFromIdx + 1].Should().Be(logTerm);
var cmd = new TruncateLog {
TruncateFromIndex = truncateFromIdx
};
TransitionNodeFromInitialState(raftNode, NodeState.Follower);
raftNode.FireAtStateMachine <TruncateLog>();
// Act
raftNode.Handle(cmd);
// Assert
raftNode.Data.Log[truncateFromIdx].Should().Be(logTerm);
raftNode.Data.Log[truncateFromIdx + 1].Should().NotHaveValue();
}
