implemented structured cache logging (#296)

may be used as audit trail to help analyse potential cache pollution/corruption

* also added common header with timestamp to all known log targets
* made `Oid::operator bool` explicit to avoid logging/text format mishaps
* made `HttpClient::operator bool` explicit

1 files changed, 32 insertions, 7 deletions

diff --git a/src/zenserver/diag/logging.cpp b/src/zenserver/diag/logging.cpp
index 24c7572f4..e6192c7c0 100644
--- a/src/zenserver/diag/logging.cpp
+++ b/src/zenserver/diag/logging.cpp
@@ -18,6 +18,8 @@ ZEN_THIRD_PARTY_INCLUDES_END
 
 #include <zencore/compactbinary.h>
 #include <zencore/filesystem.h>
+#include <zencore/fmtutils.h>
+#include <zencore/session.h>
 #include <zencore/string.h>
 
 #include <chrono>
@@ -415,30 +417,45 @@ InitializeLogging(const ZenServerOptions& GlobalOptions)
 	}
 #endif
 
-	// HTTP server request logging
+	std::vector<std::shared_ptr<spdlog::logger>> KnownLoggers{spdlog::default_logger()};
 
-	std::filesystem::path HttpLogPath = GlobalOptions.DataDir / "logs" / "http.log";
+	auto RegisterLogger = [&](std::shared_ptr<spdlog::logger> Logger) {
+		spdlog::register_logger(Logger);
+		KnownLoggers.push_back(Logger);
+	};
 
+	// HTTP server request logging
+	std::filesystem::path HttpLogPath = GlobalOptions.DataDir / "logs" / "http.log";
 	// spdlog can't create directories that starts with `\\?\` so we make sure the folder exists before creating the logger instance
 	zen::CreateDirectories(HttpLogPath.parent_path());
-
 	auto HttpSink = std::make_shared<spdlog::sinks::rotating_file_sink_mt>(zen::PathToUtf8(HttpLogPath),
 																		   /* max size */ 128 * 1024 * 1024,
 																		   /* max files */ 16,
 																		   /* rotate on open */ true);
 
 	auto HttpLogger = std::make_shared<spdlog::logger>("http_requests", HttpSink);
-	spdlog::register_logger(HttpLogger);
+	RegisterLogger(HttpLogger);
+
+	// Cache request logging
+	std::filesystem::path CacheLogPath = GlobalOptions.DataDir / "logs" / "z$.log";
+	zen::CreateDirectories(CacheLogPath.parent_path());
+	auto CacheSink = std::make_shared<spdlog::sinks::rotating_file_sink_mt>(zen::PathToUtf8(CacheLogPath),
+																			/* max size */ 128 * 1024 * 1024,
+																			/* max files */ 16,
+																			/* rotate on open */ false);
+
+	auto CacheLogger = std::make_shared<spdlog::logger>("z$", CacheSink);
+	RegisterLogger(CacheLogger);
 
 	// Jupiter - only log upstream HTTP traffic to file
 
 	auto JupiterLogger = std::make_shared<spdlog::logger>("jupiter", FileSink);
-	spdlog::register_logger(JupiterLogger);
+	RegisterLogger(JupiterLogger);
 
 	// Zen - only log upstream HTTP traffic to file
 
 	auto ZenClientLogger = std::make_shared<spdlog::logger>("zenclient", FileSink);
-	spdlog::register_logger(ZenClientLogger);
+	RegisterLogger(ZenClientLogger);
 
 	// Configure all registered loggers according to settings
 
@@ -455,7 +472,15 @@ InitializeLogging(const ZenServerOptions& GlobalOptions)
 	{
 		FileSink->set_pattern("[%C-%m-%d.%e %T] [%n] [%l] %v");
 	}
-	DefaultLogger.info("log starting at {}", zen::DateTime::Now().ToIso8601());
+
+	const std::string StartLogTime	  = zen::DateTime::Now().ToIso8601();
+	const zen::Oid	  ServerSessionId = zen::GetSessionId();
+
+	for (auto& Logger : KnownLoggers)
+	{
+		Logger->info("log starting at {}", StartLogTime);
+		Logger->info("server session id: {}", ServerSessionId);
+	}
 }
 
 void