1 files changed, 430 insertions, 0 deletions
diff --git a/src/zencompute/timeline/workertimeline.cpp b/src/zencompute/timeline/workertimeline.cpp
new file mode 100644
index 000000000..88ef5b62d
--- /dev/null
+++ b/src/zencompute/timeline/workertimeline.cpp
@@ -0,0 +1,430 @@
+// Copyright Epic Games, Inc. All Rights Reserved.
+
+#include "workertimeline.h"
+
+#if ZEN_WITH_COMPUTE_SERVICES
+
+#	include <zencore/basicfile.h>
+#	include <zencore/compactbinary.h>
+#	include <zencore/compactbinarybuilder.h>
+#	include <zencore/compactbinaryfile.h>
+
+#	include <algorithm>
+
+namespace zen::compute {
+
+WorkerTimeline::WorkerTimeline(std::string_view WorkerId) : m_WorkerId(WorkerId)
+{
+}
+
+WorkerTimeline::~WorkerTimeline()
+{
+}
+
+void
+WorkerTimeline::RecordProvisioned()
+{
+	AppendEvent({
+		.Type	   = EventType::WorkerProvisioned,
+		.Timestamp = DateTime::Now(),
+	});
+}
+
+void
+WorkerTimeline::RecordDeprovisioned()
+{
+	AppendEvent({
+		.Type	   = EventType::WorkerDeprovisioned,
+		.Timestamp = DateTime::Now(),
+	});
+}
+
+void
+WorkerTimeline::RecordActionAccepted(int ActionLsn, const IoHash& ActionId)
+{
+	AppendEvent({
+		.Type	   = EventType::ActionAccepted,
+		.Timestamp = DateTime::Now(),
+		.ActionLsn = ActionLsn,
+		.ActionId  = ActionId,
+	});
+}
+
+void
+WorkerTimeline::RecordActionRejected(int ActionLsn, const IoHash& ActionId, std::string_view Reason)
+{
+	AppendEvent({
+		.Type	   = EventType::ActionRejected,
+		.Timestamp = DateTime::Now(),
+		.ActionLsn = ActionLsn,
+		.ActionId  = ActionId,
+		.Reason	   = std::string(Reason),
+	});
+}
+
+void
+WorkerTimeline::RecordActionStateChanged(int				 ActionLsn,
+										 const IoHash&		 ActionId,
+										 RunnerAction::State PreviousState,
+										 RunnerAction::State NewState)
+{
+	AppendEvent({
+		.Type		   = EventType::ActionStateChanged,
+		.Timestamp	   = DateTime::Now(),
+		.ActionLsn	   = ActionLsn,
+		.ActionId	   = ActionId,
+		.ActionState   = NewState,
+		.PreviousState = PreviousState,
+	});
+}
+
+std::vector<WorkerTimeline::Event>
+WorkerTimeline::QueryTimeline(DateTime StartTime, DateTime EndTime) const
+{
+	std::vector<Event> Result;
+
+	m_EventsLock.WithSharedLock([&] {
+		for (const auto& Evt : m_Events)
+		{
+			if (Evt.Timestamp >= StartTime && Evt.Timestamp <= EndTime)
+			{
+				Result.push_back(Evt);
+			}
+		}
+	});
+
+	return Result;
+}
+
+std::vector<WorkerTimeline::Event>
+WorkerTimeline::QueryRecent(int Limit) const
+{
+	std::vector<Event> Result;
+
+	m_EventsLock.WithSharedLock([&] {
+		const int Count = std::min(Limit, gsl::narrow<int>(m_Events.size()));
+		auto	  It	= m_Events.end() - Count;
+		Result.assign(It, m_Events.end());
+	});
+
+	return Result;
+}
+
+size_t
+WorkerTimeline::GetEventCount() const
+{
+	size_t Count = 0;
+	m_EventsLock.WithSharedLock([&] { Count = m_Events.size(); });
+	return Count;
+}
+
+WorkerTimeline::TimeRange
+WorkerTimeline::GetTimeRange() const
+{
+	TimeRange Range;
+	m_EventsLock.WithSharedLock([&] {
+		if (!m_Events.empty())
+		{
+			Range.First = m_Events.front().Timestamp;
+			Range.Last	= m_Events.back().Timestamp;
+		}
+	});
+	return Range;
+}
+
+void
+WorkerTimeline::AppendEvent(Event&& Evt)
+{
+	m_EventsLock.WithExclusiveLock([&] {
+		while (m_Events.size() >= m_MaxEvents)
+		{
+			m_Events.pop_front();
+		}
+
+		m_Events.push_back(std::move(Evt));
+	});
+}
+
+const char*
+WorkerTimeline::ToString(EventType Type)
+{
+	switch (Type)
+	{
+		case EventType::WorkerProvisioned:
+			return "provisioned";
+		case EventType::WorkerDeprovisioned:
+			return "deprovisioned";
+		case EventType::ActionAccepted:
+			return "accepted";
+		case EventType::ActionRejected:
+			return "rejected";
+		case EventType::ActionStateChanged:
+			return "state_changed";
+		default:
+			return "unknown";
+	}
+}
+
+static WorkerTimeline::EventType
+EventTypeFromString(std::string_view Str)
+{
+	if (Str == "provisioned")
+		return WorkerTimeline::EventType::WorkerProvisioned;
+	if (Str == "deprovisioned")
+		return WorkerTimeline::EventType::WorkerDeprovisioned;
+	if (Str == "accepted")
+		return WorkerTimeline::EventType::ActionAccepted;
+	if (Str == "rejected")
+		return WorkerTimeline::EventType::ActionRejected;
+	if (Str == "state_changed")
+		return WorkerTimeline::EventType::ActionStateChanged;
+	return WorkerTimeline::EventType::WorkerProvisioned;
+}
+
+void
+WorkerTimeline::WriteTo(const std::filesystem::path& Path) const
+{
+	CbObjectWriter Cbo;
+	Cbo << "worker_id" << m_WorkerId;
+
+	m_EventsLock.WithSharedLock([&] {
+		if (!m_Events.empty())
+		{
+			Cbo.AddDateTime("time_first", m_Events.front().Timestamp);
+			Cbo.AddDateTime("time_last", m_Events.back().Timestamp);
+		}
+
+		Cbo.BeginArray("events");
+		for (const auto& Evt : m_Events)
+		{
+			Cbo.BeginObject();
+			Cbo << "type" << ToString(Evt.Type);
+			Cbo.AddDateTime("ts", Evt.Timestamp);
+
+			if (Evt.ActionLsn != 0)
+			{
+				Cbo << "lsn" << Evt.ActionLsn;
+				Cbo << "action_id" << Evt.ActionId;
+			}
+
+			if (Evt.Type == EventType::ActionStateChanged)
+			{
+				Cbo << "prev_state" << static_cast<int32_t>(Evt.PreviousState);
+				Cbo << "state" << static_cast<int32_t>(Evt.ActionState);
+			}
+
+			if (!Evt.Reason.empty())
+			{
+				Cbo << "reason" << std::string_view(Evt.Reason);
+			}
+
+			Cbo.EndObject();
+		}
+		Cbo.EndArray();
+	});
+
+	CbObject Obj = Cbo.Save();
+
+	BasicFile File(Path, BasicFile::Mode::kTruncate);
+	File.Write(Obj.GetBuffer().GetView(), 0);
+}
+
+void
+WorkerTimeline::ReadFrom(const std::filesystem::path& Path)
+{
+	CbObjectFromFile Loaded = LoadCompactBinaryObject(Path);
+	CbObject		 Root	= std::move(Loaded.Object);
+
+	if (!Root)
+	{
+		return;
+	}
+
+	std::deque<Event> LoadedEvents;
+
+	for (CbFieldView Field : Root["events"].AsArrayView())
+	{
+		CbObjectView EventObj = Field.AsObjectView();
+
+		Event Evt;
+		Evt.Type	  = EventTypeFromString(EventObj["type"].AsString());
+		Evt.Timestamp = EventObj["ts"].AsDateTime();
+
+		Evt.ActionLsn = EventObj["lsn"].AsInt32();
+		Evt.ActionId  = EventObj["action_id"].AsHash();
+
+		if (Evt.Type == EventType::ActionStateChanged)
+		{
+			Evt.PreviousState = static_cast<RunnerAction::State>(EventObj["prev_state"].AsInt32());
+			Evt.ActionState	  = static_cast<RunnerAction::State>(EventObj["state"].AsInt32());
+		}
+
+		std::string_view Reason = EventObj["reason"].AsString();
+		if (!Reason.empty())
+		{
+			Evt.Reason = std::string(Reason);
+		}
+
+		LoadedEvents.push_back(std::move(Evt));
+	}
+
+	m_EventsLock.WithExclusiveLock([&] { m_Events = std::move(LoadedEvents); });
+}
+
+WorkerTimeline::TimeRange
+WorkerTimeline::ReadTimeRange(const std::filesystem::path& Path)
+{
+	CbObjectFromFile Loaded = LoadCompactBinaryObject(Path);
+
+	if (!Loaded.Object)
+	{
+		return {};
+	}
+
+	return {
+		.First = Loaded.Object["time_first"].AsDateTime(),
+		.Last  = Loaded.Object["time_last"].AsDateTime(),
+	};
+}
+
+// WorkerTimelineStore
+
+static constexpr std::string_view kTimelineExtension = ".ztimeline";
+
+WorkerTimelineStore::WorkerTimelineStore(std::filesystem::path PersistenceDir) : m_PersistenceDir(std::move(PersistenceDir))
+{
+	std::error_code Ec;
+	std::filesystem::create_directories(m_PersistenceDir, Ec);
+}
+
+Ref<WorkerTimeline>
+WorkerTimelineStore::GetOrCreate(std::string_view WorkerId)
+{
+	// Fast path: check if it already exists in memory
+	{
+		RwLock::SharedLockScope _(m_Lock);
+		auto					It = m_Timelines.find(std::string(WorkerId));
+		if (It != m_Timelines.end())
+		{
+			return It->second;
+		}
+	}
+
+	// Slow path: create under exclusive lock, loading from disk if available
+	RwLock::ExclusiveLockScope _(m_Lock);
+
+	auto& Entry = m_Timelines[std::string(WorkerId)];
+	if (!Entry)
+	{
+		Entry = Ref<WorkerTimeline>(new WorkerTimeline(WorkerId));
+
+		std::filesystem::path Path = TimelinePath(WorkerId);
+		std::error_code		  Ec;
+		if (std::filesystem::is_regular_file(Path, Ec))
+		{
+			Entry->ReadFrom(Path);
+		}
+	}
+	return Entry;
+}
+
+Ref<WorkerTimeline>
+WorkerTimelineStore::Find(std::string_view WorkerId)
+{
+	RwLock::SharedLockScope _(m_Lock);
+	auto					It = m_Timelines.find(std::string(WorkerId));
+	if (It != m_Timelines.end())
+	{
+		return It->second;
+	}
+	return {};
+}
+
+std::vector<std::string>
+WorkerTimelineStore::GetActiveWorkerIds() const
+{
+	std::vector<std::string> Result;
+
+	RwLock::SharedLockScope $(m_Lock);
+	Result.reserve(m_Timelines.size());
+	for (const auto& [Id, _] : m_Timelines)
+	{
+		Result.push_back(Id);
+	}
+
+	return Result;
+}
+
+std::vector<WorkerTimelineStore::WorkerTimelineInfo>
+WorkerTimelineStore::GetAllWorkerInfo() const
+{
+	std::unordered_map<std::string, WorkerTimeline::TimeRange> InfoMap;
+
+	{
+		RwLock::SharedLockScope _(m_Lock);
+		for (const auto& [Id, Timeline] : m_Timelines)
+		{
+			InfoMap[Id] = Timeline->GetTimeRange();
+		}
+	}
+
+	std::error_code Ec;
+	for (const auto& Entry : std::filesystem::directory_iterator(m_PersistenceDir, Ec))
+	{
+		if (!Entry.is_regular_file())
+		{
+			continue;
+		}
+
+		const auto& Path = Entry.path();
+		if (Path.extension().string() != kTimelineExtension)
+		{
+			continue;
+		}
+
+		std::string Id = Path.stem().string();
+		if (InfoMap.find(Id) == InfoMap.end())
+		{
+			InfoMap[Id] = WorkerTimeline::ReadTimeRange(Path);
+		}
+	}
+
+	std::vector<WorkerTimelineInfo> Result;
+	Result.reserve(InfoMap.size());
+	for (auto& [Id, Range] : InfoMap)
+	{
+		Result.push_back({.WorkerId = std::move(Id), .Range = Range});
+	}
+	return Result;
+}
+
+void
+WorkerTimelineStore::Save(std::string_view WorkerId)
+{
+	RwLock::SharedLockScope _(m_Lock);
+	auto					It = m_Timelines.find(std::string(WorkerId));
+	if (It != m_Timelines.end())
+	{
+		It->second->WriteTo(TimelinePath(WorkerId));
+	}
+}
+
+void
+WorkerTimelineStore::SaveAll()
+{
+	RwLock::SharedLockScope _(m_Lock);
+	for (const auto& [Id, Timeline] : m_Timelines)
+	{
+		Timeline->WriteTo(TimelinePath(Id));
+	}
+}
+
+std::filesystem::path
+WorkerTimelineStore::TimelinePath(std::string_view WorkerId) const
+{
+	return m_PersistenceDir / (std::string(WorkerId) + std::string(kTimelineExtension));
+}
+
+}  // namespace zen::compute
+
+#endif	// ZEN_WITH_COMPUTE_SERVICES