add `--write-config` to zenserver options (#382)

- Feature: `zen up` command has two new command line options
  - `--config <file_path>` tells zenserver to start with a specific config file
  - `--owner-pid <pid>` tells zenserver to start with a owning process id
- Feature: `zen attach` command to add additional owning processes to a running zenserver instance
  - `--owner-pid <pid>` adds pid to running zenserver instance list of owning processes
- Feature: `--write-config` command line option for zenserver
  - `--write-config <file_path>` path to a file which will contain a lua config file for zenserver combining all command line options and optional lua config files
- Improvement: `zen up` command will check if zenserver is currently running before starting up a new instance

1 files changed, 23 insertions, 7 deletions

diff --git a/src/zenserver/config.cpp b/src/zenserver/config.cpp
index 2d286b02a..1f5a3eb21 100644
--- a/src/zenserver/config.cpp
+++ b/src/zenserver/config.cpp
@@ -10,6 +10,7 @@
 #include <zencore/iobuffer.h>
 #include <zencore/string.h>
 #include <zenhttp/zenhttp.h>
+#include <zenutil/basicfile.h>
 
 ZEN_THIRD_PARTY_INCLUDES_START
 #include <fmt/format.h>
@@ -136,15 +137,15 @@ ParseBucketConfigs(std::span<std::string> Buckets)
 }
 
 static std::string
-MakeSafePath(const std::string& Path)
+MakeSafePath(const std::string_view Path)
 {
 #if ZEN_PLATFORM_WINDOWS
 	if (Path.empty())
 	{
-		return Path;
+		return std::string(Path);
 	}
 
-	std::string FixedPath = Path;
+	std::string FixedPath(Path);
 	std::replace(FixedPath.begin(), FixedPath.end(), '/', '\\');
 	if (!FixedPath.starts_with("\\\\?\\"))
 	{
@@ -152,7 +153,7 @@ MakeSafePath(const std::string& Path)
 	}
 	return FixedPath;
 #else
-	return Path;
+	return std::string(Path);
 #endif
 };
 
@@ -768,7 +769,10 @@ private:
 }  // namespace LuaConfig
 
 void
-ParseConfigFile(const std::filesystem::path& Path, ZenServerOptions& ServerOptions, const cxxopts::ParseResult& CmdLineResult)
+ParseConfigFile(const std::filesystem::path& Path,
+				ZenServerOptions&			 ServerOptions,
+				const cxxopts::ParseResult&	 CmdLineResult,
+				std::string_view			 OutputConfigFile)
 {
 	using namespace std::literals;
 
@@ -923,6 +927,16 @@ ParseConfigFile(const std::filesystem::path& Path, ZenServerOptions& ServerOptio
 	{
 		LuaOptions.Touch("server.objectstore.buckets"sv);
 	}
+
+	if (!OutputConfigFile.empty())
+	{
+		std::filesystem::path			  WritePath(MakeSafePath(OutputConfigFile));
+		zen::ExtendableStringBuilder<512> ConfigStringBuilder;
+		LuaOptions.Print(ConfigStringBuilder, CmdLineResult);
+		zen::BasicFile Output;
+		Output.Open(WritePath, zen::BasicFile::Mode::kTruncate);
+		Output.Write(ConfigStringBuilder.Data(), ConfigStringBuilder.Size(), 0);
+	}
 }
 
 void
@@ -943,6 +957,7 @@ ParseCliOptions(int argc, char* argv[], ZenServerOptions& ServerOptions)
 	std::string ContentDir;
 	std::string AbsLogFile;
 	std::string ConfigFile;
+	std::string OutputConfigFile;
 
 	cxxopts::Options options("zenserver", "Zen Server");
 	options.add_options()("dedicated",
@@ -956,6 +971,7 @@ ParseCliOptions(int argc, char* argv[], ZenServerOptions& ServerOptions)
 	options.add_options()("content-dir", "Frontend content directory", cxxopts::value<std::string>(ContentDir));
 	options.add_options()("abslog", "Path to log file", cxxopts::value<std::string>(AbsLogFile));
 	options.add_options()("config", "Path to Lua config file", cxxopts::value<std::string>(ConfigFile));
+	options.add_options()("write-config", "Path to output Lua config file", cxxopts::value<std::string>(OutputConfigFile));
 	options.add_options()("no-sentry",
 						  "Disable Sentry crash handler",
 						  cxxopts::value<bool>(ServerOptions.NoSentry)->default_value("false"));
@@ -1380,11 +1396,11 @@ ParseCliOptions(int argc, char* argv[], ZenServerOptions& ServerOptions)
 
 		if (!ServerOptions.ConfigFile.empty())
 		{
-			ParseConfigFile(ServerOptions.ConfigFile, ServerOptions, result);
+			ParseConfigFile(ServerOptions.ConfigFile, ServerOptions, result, OutputConfigFile);
 		}
 		else
 		{
-			ParseConfigFile(ServerOptions.DataDir / "zen_cfg.lua", ServerOptions, result);
+			ParseConfigFile(ServerOptions.DataDir / "zen_cfg.lua", ServerOptions, result, OutputConfigFile);
 		}
 
 		ValidateOptions(ServerOptions);