public void NodeStaysAFollowerWhenReceiveAppendEntries()
{
using (Helpers.InitLog4Net())
{
var settings = Helpers.BuildNodeSettings("1", new[] { "1", "2", "3", "4", "5" });
settings.TimeoutInMs = 20;
var middleware = new Middleware();
var node = new Node<string>(TestHelpers.GetPool().BuildSequencer(), settings, middleware, new StateMachine());
using (node)
{
node.Initialize();
// should switch to candidate
Check.That(this.WaitState(node, NodeStatus.Candidate, 40)).IsTrue();
// now we pretend there is a leader
var message = new AppendEntries<string>
{
LeaderId = "2",
LeaderTerm = 5,
PrevLogIndex = -1,
PrevLogTerm = 0
};
var entry = new LogEntry<string>("dummy", 1L);
message.Entries = new[] { entry };
middleware.SendMessage("1", message);
Check.That(this.WaitState(node, NodeStatus.Follower, 30)).IsTrue();
Check.That(node.State.LogEntries.Count).IsEqualTo(1);
}
}
}
public void CheckThatExceptionsAreFiltered()
{
var test = new Middleware(false);
test.RegisterEndPoint("test", x => { throw new Exception(); });
Check.That( ()=> test.SendMessage("test", 1)).DoesNotThrow();
}
public void EmptyLogIsfilledTest()
{
using (Helpers.InitLog4Net())
{
var middleware = new Middleware();
var settings = Helpers.BuildNodeSettings("1", new[] { "1", "2" });
settings.TimeoutInMs = 10;
using (var leader = new Node<string>(TestHelpers.GetPool().BuildSequencer(), settings, middleware, new StateMachine()))
{
// we inject
leader.State.AppendEntries(
-1, new[] { new LogEntry<string>("one"), new LogEntry<string>("two"), });
middleware.RegisterEndPoint("2", this.OnMessage);
lock (this.synchro)
{
leader.Initialize();
const int MaxDelay = 3000;
var initIndex = this.WaitForLogSynchro(MaxDelay, middleware, leader);
Check.That(initIndex).IsEqualTo(2);
}
}
}
}
public void CommitIndexIsProperlyEstablished()
{
using (Helpers.InitLog4Net())
{
var middleware = new Middleware();
var settings = Helpers.BuildNodeSettings("1", new[] { "1", "2" });
settings.TimeoutInMs = 1;
using (var leader = new Node<string>(TestHelpers.GetPool().BuildSequencer(), settings, middleware, new StateMachine()))
{
// we inject
leader.State.AppendEntries(-1, new[] { new LogEntry<string>("one"), new LogEntry<string>("two"), new LogEntry<string>("3") });
middleware.RegisterEndPoint("2", this.OnMessage);
lock (this.synchro)
{
leader.Initialize();
const int MaxDelay = 300000;
var initIndex = this.WaitForLogSynchro(MaxDelay, middleware, leader);
Check.That(initIndex).IsEqualTo(3);
// let sometime for the leader to commit entries
Thread.Sleep(50);
Check.That(leader.LastCommit).IsEqualTo(2);
}
}
}
}
public void CheckThatDoubleRegisterFails()
{
var test = new Middleware(false);
test.RegisterEndPoint("test", this.MessageReceived);
Check.ThatCode(() => test.RegisterEndPoint("test", this.MessageReceived))
.Throws<InvalidOperationException>();
;
}
public void SendCommandToASingleNode()
{
var middleware = new Middleware();
// have a cluster of one
var settings = Helpers.BuildNodeSettings("1", new[] { "1" });
settings.TimeoutInMs = 10;
// create a cluster of one node, so there is no ambiguity about who is the leader
var leader = new Node<string>(TestHelpers.GetPool().BuildSequencer(), settings, middleware, new StateMachine());
}
public void CheckThatMessageIsReceived()
{
this.lastMessage = null;
var test = new Middleware(false);
test.RegisterEndPoint("point", this.MessageReceived);
var newMessage = new object();
test.SendMessage("point", newMessage);
Check.That(this.lastMessage).IsSameReferenceThan(newMessage);
}
public void GivenIHaveDeployedInstance(int p0)
{
var nodeIds = new[] { "1", "2", "3", "4", "5" };
this.middleware = new Middleware();
this.testedNodes = new Node<string>[p0];
for (var i = 0; i < p0; i++)
{
var testedNode = new Node<string>(TestHelpers.GetPool().BuildSequencer(), Helpers.BuildNodeSettings(nodeIds[i], nodeIds), middleware, new StateMachine());
this.testedNodes[i] = testedNode;
testedNode.Initialize();
}
}
public void ProtocolTest()
{
var settings = Helpers.BuildNodeSettings("1", new[] { "1" });
settings.TimeoutInMs = 5;
var raftMiddleware = new Middleware();
var node = new Node<string>(TestHelpers.GetPool().BuildSequencer(), settings, raftMiddleware, new StateMachine());
node.Initialize();
Thread.Sleep(50);
Check.ThatEnum(node.Status).IsEqualTo(NodeStatus.Leader);
raftMiddleware.SendMessage("1", new SendCommand<string>("test"));
}
private void RequestAndGetVote(Middleware middleware, Node<string> node, bool succeed)
{
lock (this.synchro)
{
// request a vote, and lie about our capacity
middleware.SendMessage("1", new RequestVote(3, "2", 2, 2));
if (this.lastMessage == null)
{
Monitor.Wait(this.synchro, 100);
}
Check.That(this.lastMessage).IsNotEqualTo(null).And.IsInstanceOf<GrantVote>();
var answer = this.lastMessage as GrantVote;
if (succeed)
{
Check.That(node.State.VotedFor).IsEqualTo("2");
// did we get the vote?
Check.That(answer.VoteGranted).IsTrue();
}
else
{
Check.That(answer.VoteGranted).IsFalse();
}
}
}
// helper to initilize setip
private Middleware InitNodes(out Node<string> node)
{
var middleware = new Middleware(false);
var settings = Helpers.BuildNodeSettings("1", new[] { "1", "2", "3", "4", "5" });
settings.TimeoutInMs = Timeout.Infinite; // no timeout
node = new Node<string>(middleware.RootUnitOfExecution.BuildSequencer(), settings, middleware, new StateMachine());
node.Initialize();
middleware.RegisterEndPoint("2", this.MessageReceived);
return middleware;
}
public void InitializationTests()
{
var test = new Middleware(false);
Check.That(() => test.RegisterEndPoint("testPoint", this.MessageReceived)).DoesNotThrow();
}
public void CheckThatRegisterEndPointFailsForNullOrEmptyAddress()
{
var test = new Middleware(false);
Check.ThatCode(() => test.RegisterEndPoint(string.Empty, this.MessageReceived)).Throws<ArgumentNullException>();
}
public void CheckThatRegisterEndPointFailsForNullHandler()
{
var test = new Middleware(false);
Check.ThatCode( () => test.RegisterEndPoint("test", null)) .Throws<ArgumentNullException>();
}
private int WaitForLogSynchro(int maxDelay, Middleware middleware, Node<string> leader)
{
var initIndex = 0;
var timer = new Stopwatch();
timer.Start();
for (;;)
{
var millisecondsTimeout = Math.Max(maxDelay - (int)timer.ElapsedMilliseconds, 0);
if (Debugger.IsAttached)
{
millisecondsTimeout = Timeout.Infinite;
}
if (this.lastMessage == null && !Monitor.Wait(this.synchro, millisecondsTimeout))
{
break;
}
var message = this.lastMessage;
this.lastMessage = null;
if (message is RequestVote)
{
// we vote for the leader
middleware.SendMessage("1", new GrantVote(true, "2", 0));
}
if (message is AppendEntries<string>)
{
var appendMessage = message as AppendEntries<string>;
if (appendMessage.PrevLogIndex != initIndex - 1)
{
middleware.SendMessage("1", new AppendEntriesAck("2", 0, false));
}
else
{
initIndex += (int)appendMessage.Entries.Count();
middleware.SendMessage("1", new AppendEntriesAck("2", 0, true));
if (initIndex == leader.State.LogEntries.Count)
{
break;
}
}
}
if (millisecondsTimeout == 0)
{
break;
}
}
return initIndex;
}
