stats: Implemented new stats endpoint

Stats are exposed under /stats/{id}, so for example structured cache stats are exposed under /stats/z$

The separate endpoint makes it easier to separate request handling to ensure stats/status endpoints still respond if the regular request queue is somehow saturated or otherwise not behaving

There is also a /status endpoint which is similar and is targeted towards lightweight health monitoring

4 files changed, 61 insertions, 5 deletions

diff --git a/zenserver/monitoring/httpstats.cpp b/zenserver/monitoring/httpstats.cpp
index a82cfda50..de04294d0 100644
--- a/zenserver/monitoring/httpstats.cpp
+++ b/zenserver/monitoring/httpstats.cpp
@@ -19,14 +19,31 @@ HttpStatsService::BaseUri() const
 }
 
 void
+HttpStatsService::RegisterHandler(std::string_view Id, IHttpStatsProvider& Provider)
+{
+	RwLock::ExclusiveLockScope _(m_Lock);
+	m_Providers.insert_or_assign(std::string(Id), &Provider);
+}
+
+void
 HttpStatsService::HandleRequest(HttpServerRequest& Request)
 {
 	using namespace std::literals;
 
+	std::string_view Key = Request.RelativeUri();
+
 	switch (Request.RequestVerb())
 	{
+		case HttpVerb::kHead:
 		case HttpVerb::kGet:
-			return Request.WriteResponse(HttpResponseCode::OK, HttpContentType::kText, u8"OK!"sv);
+			if (auto It = m_Providers.find(std::string{Key}); It != end(m_Providers))
+			{
+				return It->second->HandleStatsRequest(Request);
+			}
+
+			[[fallthrough]];
+		default:
+			return;
 	}
 }
 
diff --git a/zenserver/monitoring/httpstats.h b/zenserver/monitoring/httpstats.h
index 9da48233b..1c3c79dd0 100644
--- a/zenserver/monitoring/httpstats.h
+++ b/zenserver/monitoring/httpstats.h
@@ -2,11 +2,18 @@
 
 #pragma once
 
-#include <zenhttp/httpserver.h>
 #include <zencore/logging.h>
+#include <zenhttp/httpserver.h>
+
+#include <map>
 
 namespace zen {
 
+struct IHttpStatsProvider
+{
+	virtual void HandleStatsRequest(HttpServerRequest& Request) = 0;
+};
+
 class HttpStatsService : public HttpService
 {
 public:
@@ -15,12 +22,16 @@ public:
 
 	virtual const char* BaseUri() const override;
 	virtual void		HandleRequest(HttpServerRequest& Request) override;
+	void				RegisterHandler(std::string_view Id, IHttpStatsProvider& Provider);
 
 private:
 	spdlog::logger&	  m_Log;
 	HttpRequestRouter m_Router;
 
 	inline spdlog::logger& Log() { return m_Log; }
+
+	RwLock									   m_Lock;
+	std::map<std::string, IHttpStatsProvider*> m_Providers;
 };
 
 }  // namespace zen
\ No newline at end of file
diff --git a/zenserver/monitoring/httpstatus.cpp b/zenserver/monitoring/httpstatus.cpp
index c18bf6c1f..e12662b1c 100644
--- a/zenserver/monitoring/httpstatus.cpp
+++ b/zenserver/monitoring/httpstatus.cpp
@@ -15,7 +15,14 @@ HttpStatusService::~HttpStatusService()
 const char*
 HttpStatusService::BaseUri() const
 {
-	return "/statUs/";
+	return "/status/";
+}
+
+void
+HttpStatusService::RegisterHandler(std::string_view Id, IHttpStatusProvider& Provider)
+{
+	RwLock::ExclusiveLockScope _(m_Lock);
+	m_Providers.insert_or_assign(std::string(Id), &Provider);
 }
 
 void
@@ -23,10 +30,20 @@ HttpStatusService::HandleRequest(HttpServerRequest& Request)
 {
 	using namespace std::literals;
 
+	std::string_view Key = Request.RelativeUri();
+
 	switch (Request.RequestVerb())
 	{
+		case HttpVerb::kHead:
 		case HttpVerb::kGet:
-			return Request.WriteResponse(HttpResponseCode::OK, HttpContentType::kText, u8"OK!"sv);
+			if (auto It = m_Providers.find(std::string{Key}); It != end(m_Providers))
+			{
+				return It->second->HandleStatusRequest(Request);
+			}
+
+			[[fallthrough]];
+		default:
+			return;
 	}
 }
 
diff --git a/zenserver/monitoring/httpstatus.h b/zenserver/monitoring/httpstatus.h
index f5c6bd616..8f069f760 100644
--- a/zenserver/monitoring/httpstatus.h
+++ b/zenserver/monitoring/httpstatus.h
@@ -2,11 +2,18 @@
 
 #pragma once
 
-#include <zenhttp/httpserver.h>
 #include <zencore/logging.h>
+#include <zenhttp/httpserver.h>
+
+#include <map>
 
 namespace zen {
 
+struct IHttpStatusProvider
+{
+	virtual void HandleStatusRequest(HttpServerRequest& Request) = 0;
+};
+
 class HttpStatusService : public HttpService
 {
 public:
@@ -15,11 +22,15 @@ public:
 
 	virtual const char* BaseUri() const override;
 	virtual void		HandleRequest(HttpServerRequest& Request) override;
+	void				RegisterHandler(std::string_view Id, IHttpStatusProvider& Provider);
 
 private:
 	spdlog::logger&	  m_Log;
 	HttpRequestRouter m_Router;
 
+	RwLock										m_Lock;
+	std::map<std::string, IHttpStatusProvider*> m_Providers;
+
 	inline spdlog::logger& Log() { return m_Log; }
 };