hub async provision/deprovision/hibernate/wake (#891)HEADmain

- Improvement: Hub provision, deprovision, hibernate, and wake operations are now async. HTTP requests returns 202 Accepted while the operation completes in the background
- Improvement: Hub returns 202 Accepted (instead of 409 Conflict) when the same async operation is already in progress for a module
- Improvement: Hub returns 200 OK when a requested state transition is already satisfied

1 files changed, 82 insertions, 83 deletions

diff --git a/src/zenserver/hub/httphubservice.cpp b/src/zenserver/hub/httphubservice.cpp
index 34f4294e4..032a61f08 100644
--- a/src/zenserver/hub/httphubservice.cpp
+++ b/src/zenserver/hub/httphubservice.cpp
@@ -11,6 +11,37 @@
 
 namespace zen {
 
+namespace {
+	bool HandleFailureResults(HttpServerRequest& Request, const Hub::Response& Resp)
+	{
+		if (Resp.ResponseCode == Hub::EResponseCode::Rejected)
+		{
+			if (Resp.Message.empty())
+			{
+				Request.WriteResponse(HttpResponseCode::Conflict);
+			}
+			else
+			{
+				Request.WriteResponse(HttpResponseCode::Conflict, HttpContentType::kText, Resp.Message);
+			}
+			return true;
+		}
+		if (Resp.ResponseCode == Hub::EResponseCode::NotFound)
+		{
+			if (Resp.Message.empty())
+			{
+				Request.WriteResponse(HttpResponseCode::NotFound);
+			}
+			else
+			{
+				Request.WriteResponse(HttpResponseCode::NotFound, HttpContentType::kText, Resp.Message);
+			}
+			return true;
+		}
+		return false;
+	}
+}  // namespace
+
 HttpHubService::HttpHubService(Hub& Hub) : m_Hub(Hub)
 {
 	using namespace std::literals;
@@ -83,144 +114,113 @@ HttpHubService::HttpHubService(Hub& Hub) : m_Hub(Hub)
 		[this](HttpRouterRequest& Req) {
 			std::string_view ModuleId = Req.GetCapture(1);
 
-			std::string		 FailureReason = "unknown";
-			HttpResponseCode ResponseCode  = HttpResponseCode::OK;
-
 			try
 			{
 				HubProvisionedInstanceInfo Info;
-				if (m_Hub.Provision(ModuleId, /* out */ Info, /* out */ FailureReason))
-				{
-					CbObjectWriter Obj;
-					Obj << "moduleId" << ModuleId;
-					Obj << "baseUri" << Info.BaseUri;
-					Obj << "port" << Info.Port;
-					Req.ServerRequest().WriteResponse(HttpResponseCode::OK, Obj.Save());
+				Hub::Response			   Resp = m_Hub.Provision(ModuleId, Info);
 
-					return;
-				}
-				else
+				if (HandleFailureResults(Req.ServerRequest(), Resp))
 				{
-					ResponseCode = HttpResponseCode::BadRequest;
+					return;
 				}
+
+				const HttpResponseCode HttpCode =
+					(Resp.ResponseCode == Hub::EResponseCode::Accepted) ? HttpResponseCode::Accepted : HttpResponseCode::OK;
+				CbObjectWriter Obj;
+				Obj << "moduleId" << ModuleId;
+				Obj << "baseUri" << Info.BaseUri;
+				Obj << "port" << Info.Port;
+				return Req.ServerRequest().WriteResponse(HttpCode, Obj.Save());
 			}
 			catch (const std::exception& Ex)
 			{
 				ZEN_ERROR("Exception while provisioning module '{}': {}", ModuleId, Ex.what());
-
-				FailureReason = Ex.what();
-				ResponseCode  = HttpResponseCode::InternalServerError;
+				throw;
 			}
-
-			Req.ServerRequest().WriteResponse(ResponseCode, HttpContentType::kText, FailureReason);
 		},
 		HttpVerb::kPost);
 
 	m_Router.RegisterRoute(
 		"modules/{moduleid}/deprovision",
 		[this](HttpRouterRequest& Req) {
-			std::string_view ModuleId	   = Req.GetCapture(1);
-			std::string		 FailureReason = "unknown";
+			std::string_view ModuleId = Req.GetCapture(1);
 
 			try
 			{
-				if (!m_Hub.Deprovision(std::string(ModuleId), /* out */ FailureReason))
+				Hub::Response Resp = m_Hub.Deprovision(std::string(ModuleId));
+
+				if (HandleFailureResults(Req.ServerRequest(), Resp))
 				{
-					if (FailureReason.empty())
-					{
-						return Req.ServerRequest().WriteResponse(HttpResponseCode::NotFound);
-					}
-					else
-					{
-						return Req.ServerRequest().WriteResponse(HttpResponseCode::BadRequest, HttpContentType::kText, FailureReason);
-					}
+					return;
 				}
 
+				const HttpResponseCode HttpCode =
+					(Resp.ResponseCode == Hub::EResponseCode::Accepted) ? HttpResponseCode::Accepted : HttpResponseCode::OK;
 				CbObjectWriter Obj;
 				Obj << "moduleId" << ModuleId;
-
-				return Req.ServerRequest().WriteResponse(HttpResponseCode::OK, Obj.Save());
+				return Req.ServerRequest().WriteResponse(HttpCode, Obj.Save());
 			}
 			catch (const std::exception& Ex)
 			{
 				ZEN_ERROR("Exception while deprovisioning module '{}': {}", ModuleId, Ex.what());
-
-				FailureReason = Ex.what();
+				throw;
 			}
-
-			Req.ServerRequest().WriteResponse(HttpResponseCode::InternalServerError, HttpContentType::kText, FailureReason);
 		},
 		HttpVerb::kPost);
 
 	m_Router.RegisterRoute(
 		"modules/{moduleid}/hibernate",
 		[this](HttpRouterRequest& Req) {
-			std::string_view ModuleId	   = Req.GetCapture(1);
-			std::string		 FailureReason = "unknown";
+			std::string_view ModuleId = Req.GetCapture(1);
 
 			try
 			{
-				if (!m_Hub.Hibernate(std::string(ModuleId), /* out */ FailureReason))
+				Hub::Response Resp = m_Hub.Hibernate(std::string(ModuleId));
+
+				if (HandleFailureResults(Req.ServerRequest(), Resp))
 				{
-					if (FailureReason.empty())
-					{
-						return Req.ServerRequest().WriteResponse(HttpResponseCode::NotFound);
-					}
-					else
-					{
-						return Req.ServerRequest().WriteResponse(HttpResponseCode::BadRequest, HttpContentType::kText, FailureReason);
-					}
+					return;
 				}
 
+				const HttpResponseCode HttpCode =
+					(Resp.ResponseCode == Hub::EResponseCode::Accepted) ? HttpResponseCode::Accepted : HttpResponseCode::OK;
 				CbObjectWriter Obj;
 				Obj << "moduleId" << ModuleId;
-
-				return Req.ServerRequest().WriteResponse(HttpResponseCode::OK, Obj.Save());
+				return Req.ServerRequest().WriteResponse(HttpCode, Obj.Save());
 			}
 			catch (const std::exception& Ex)
 			{
 				ZEN_ERROR("Exception while hibernating module '{}': {}", ModuleId, Ex.what());
-
-				FailureReason = Ex.what();
+				throw;
 			}
-
-			Req.ServerRequest().WriteResponse(HttpResponseCode::InternalServerError, HttpContentType::kText, FailureReason);
 		},
 		HttpVerb::kPost);
 
 	m_Router.RegisterRoute(
 		"modules/{moduleid}/wake",
 		[this](HttpRouterRequest& Req) {
-			std::string_view ModuleId	   = Req.GetCapture(1);
-			std::string		 FailureReason = "unknown";
+			std::string_view ModuleId = Req.GetCapture(1);
 
 			try
 			{
-				if (!m_Hub.Wake(std::string(ModuleId), /* out */ FailureReason))
+				Hub::Response Resp = m_Hub.Wake(std::string(ModuleId));
+
+				if (HandleFailureResults(Req.ServerRequest(), Resp))
 				{
-					if (FailureReason.empty())
-					{
-						return Req.ServerRequest().WriteResponse(HttpResponseCode::NotFound);
-					}
-					else
-					{
-						return Req.ServerRequest().WriteResponse(HttpResponseCode::BadRequest, HttpContentType::kText, FailureReason);
-					}
+					return;
 				}
 
+				const HttpResponseCode HttpCode =
+					(Resp.ResponseCode == Hub::EResponseCode::Accepted) ? HttpResponseCode::Accepted : HttpResponseCode::OK;
 				CbObjectWriter Obj;
 				Obj << "moduleId" << ModuleId;
-
-				return Req.ServerRequest().WriteResponse(HttpResponseCode::OK, Obj.Save());
+				return Req.ServerRequest().WriteResponse(HttpCode, Obj.Save());
 			}
 			catch (const std::exception& Ex)
 			{
 				ZEN_ERROR("Exception while waking module '{}': {}", ModuleId, Ex.what());
-
-				FailureReason = Ex.what();
+				throw;
 			}
-
-			Req.ServerRequest().WriteResponse(HttpResponseCode::InternalServerError, HttpContentType::kText, FailureReason);
 		},
 		HttpVerb::kPost);
 
@@ -288,27 +288,27 @@ HttpHubService::HandleModuleDelete(HttpServerRequest& Request, std::string_view
 	if (InstanceInfo.State == HubInstanceState::Provisioned || InstanceInfo.State == HubInstanceState::Hibernated ||
 		InstanceInfo.State == HubInstanceState::Crashed)
 	{
-		std::string FailureReason;
 		try
 		{
-			if (!m_Hub.Deprovision(std::string(ModuleId), FailureReason))
+			Hub::Response Resp = m_Hub.Deprovision(std::string(ModuleId));
+
+			if (HandleFailureResults(Request, Resp))
 			{
-				if (FailureReason.empty())
-				{
-					Request.WriteResponse(HttpResponseCode::NotFound);
-				}
-				else
-				{
-					Request.WriteResponse(HttpResponseCode::BadRequest, HttpContentType::kText, FailureReason);
-				}
 				return;
 			}
+
+			// TODO: nuke all related storage
+
+			const HttpResponseCode HttpCode =
+				(Resp.ResponseCode == Hub::EResponseCode::Accepted) ? HttpResponseCode::Accepted : HttpResponseCode::OK;
+			CbObjectWriter Obj;
+			Obj << "moduleId" << ModuleId;
+			return Request.WriteResponse(HttpCode, Obj.Save());
 		}
 		catch (const std::exception& Ex)
 		{
 			ZEN_ERROR("Exception while deprovisioning module '{}': {}", ModuleId, Ex.what());
-			Request.WriteResponse(HttpResponseCode::InternalServerError, HttpContentType::kText, Ex.what());
-			return;
+			throw;
 		}
 	}
 
@@ -316,7 +316,6 @@ HttpHubService::HandleModuleDelete(HttpServerRequest& Request, std::string_view
 
 	CbObjectWriter Obj;
 	Obj << "moduleId" << ModuleId;
-	Obj << "state" << ToString(InstanceInfo.State);
 	Request.WriteResponse(HttpResponseCode::OK, Obj.Save());
 }