zen hub (#574)

Initial implementation of zenserver "hub" mode. This is an experimental feature.

zenserver can be started in hub mode by specifying `hub` as the first argument to zenserver

1 files changed, 40 insertions, 0 deletions

diff --git a/src/zenserver/hub/hydration.h b/src/zenserver/hub/hydration.h
new file mode 100644
index 000000000..f86f2accf
--- /dev/null
+++ b/src/zenserver/hub/hydration.h
@@ -0,0 +1,40 @@
+// Copyright Epic Games, Inc. All Rights Reserved.
+
+#pragma once
+
+#include "zenhubserver.h"
+
+namespace zen {
+
+struct HydrationConfig
+{
+	// Location of server state to hydrate/dehydrate
+	std::filesystem::path ServerStateDir;
+	// Temporary directory available for use during hydration/dehydration
+	std::filesystem::path TempDir;
+	// Module ID of the server state being hydrated/dehydrated
+	std::string ModuleId;
+	// Back-end specific target specification (e.g. S3 bucket, file path, etc)
+	std::string TargetSpecification;
+};
+
+/**
+ * @brief State hydration strategy interface
+ *
+ * An instance of this interface is used to perform hydration OR
+ * dehydration of server state. It's expected to be used only once
+ * and not reused.
+ *
+ */
+struct HydrationStrategyBase
+{
+	virtual ~HydrationStrategyBase() = default;
+
+	virtual void Dehydrate()							  = 0;
+	virtual void Hydrate()								  = 0;
+	virtual void Configure(const HydrationConfig& Config) = 0;
+};
+
+std::unique_ptr<HydrationStrategyBase> CreateFileHydrator();
+
+}  // namespace zen