Lesson 55 - Dedicated Servers Game Mode

Source/DedicatedServers/DedicatedServers.Build.cs

@@ -20,7 +20,20 @@ public class DedicatedServers : ModuleRules
 		PrivateDependencyModuleNames.AddRange(new string[]
 		{
 			"Slate", 
-			"SlateCore"
+			"SlateCore",
+			"OpenSSL"
 		});
+		
+		//  Adds in the plugin for GameLiftServerSDK if it is the server build.
+
+		if (Target.Type == TargetType.Server)
+		{
+			PublicDependencyModuleNames.Add("GameLiftServerSDK");
+		}
+		else
+		{
+			PublicDefinitions.Add("WITH_GAMELIFT=0");
+		}
+		bEnableExceptions = true;
 	}
 }

Source/DedicatedServers/Private/Game/DS_GameMode.cpp

@@ -0,0 +1,357 @@
+// Fill out your copyright notice in the Description page of Project Settings.
+
+
+#include "DedicatedServers/Public/Game/DS_GameMode.h"
+#include "openssl/sha.h"
+#include "GameLift/GameLiftClp.h"
+#if WITH_GAMELIFT
+#include "GameLiftServerSDK.h"
+#endif
+
+DEFINE_LOG_CATEGORY(LogDS_GameMode);
+
+void ADS_GameMode::BeginPlay()
+{
+	Super::BeginPlay();
+}
+
+void ADS_GameMode::InitGame(const FString& MapName, const FString& Options, FString& ErrorMessage)
+{
+	Super::InitGame(MapName, Options, ErrorMessage);
+	CachedCommandLine = FCommandLine::Get();
+	
+	const FPortResult PortResult = cmdlineparser::details::GetConfiguredOrDefaultPort(CachedCommandLine, TEXT("port"));;
+	if (PortResult.bUsedDefaultPort)
+	{
+		UE_LOGFMT (LogDS_GameMode, Warning, "{0}", PortResult.WarningMessage);
+	}
+	
+	GameLiftConfig.ServerPort = PortResult.Port;
+	if (FParse::Param(*CachedCommandLine, TEXT("glAnywhereFleet")))
+	{
+		UE_LOGFMT(LogDS_GameMode, Log, "Fleet type: Anywhere");
+		GameLiftConfig.bIsAnywhereFleet = true;
+		GameLiftConfig.bAllOptionsFound = GetAnywhereFleetParameters(CachedCommandLine);
+		LogAnywhereFleetParameters();
+	}
+	else
+	{
+		UE_LOGFMT(LogDS_GameMode, Log, "Fleet type: EC2");
+		// TODO: EC2 configuration
+	}
+}
+
+FString ADS_GameMode::GetSHA256Hash(const FString& InString)
+{
+		
+	if (InString.IsEmpty()) 
+		return TEXT("e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855");
+
+	FSHA256Signature Hash;
+	
+	// Use OpenSSL to compute the SHA-256 hash
+	
+	FTCHARToUTF8 Utf8(InString);
+	const uint8* Bytes = reinterpret_cast<const uint8*>(Utf8.Get());
+	uint32 Length = Utf8.Length();
+	
+	
+	SHA256_CTX Sha256Context;
+	SHA256_Init(&Sha256Context);
+	SHA256_Update(&Sha256Context, Bytes,Length);
+	SHA256_Final(Hash.Signature, &Sha256Context);
+	
+	return Hash.ToString();
+}
+
+void ADS_GameMode::InitGameLift()
+{
+	#if WITH_GAMELIFT
+	UE_LOGFMT(LogDS_GameMode, Log, "Calling InitGameLift...");
+	
+	//  Get the module first
+	FGameLiftServerSDKModule* GameLiftSdkModule = &FModuleManager::LoadModuleChecked<FGameLiftServerSDKModule>("GameLiftServerSDK");
+	FGameLiftGenericOutcome InitSdkOutcome;
+
+	UE_LOGFMT(LogDS_GameMode, Log, "Initializing the GameLift Server...");
+	if (GameLiftConfig.bIsAnywhereFleet)
+	{
+		//  Define the server parameters for an Anywhere fleet.  These are not needed for a GameLift managed EC2 fleet.
+		FServerParameters ServerParametersForAnywhere;
+
+		uint32 PID = FPlatformProcess::GetCurrentProcessId();
+		FString PIDString = FString::FromInt(static_cast<int32>(PID));
+		
+		UE_LOGFMT(LogDS_GameMode, Log, "Configuring server parameters for Anywhere...");
+		//  If AnywhereFleets are being used load the command line arguments parsed earlier.
+		ServerParametersForAnywhere.m_webSocketUrl = TCHAR_TO_UTF8(*GameLiftConfig.WebSocketUrlResult.Value);
+		ServerParametersForAnywhere.m_fleetId = TCHAR_TO_UTF8((*GameLiftConfig.FleetIdResult.Value));
+		ServerParametersForAnywhere.m_hostId = TCHAR_TO_UTF8(*GameLiftConfig.HostIdResult.Value);
+		ServerParametersForAnywhere.m_processId = PIDString;
+		ServerParametersForAnywhere.m_authToken = TCHAR_TO_UTF8(*GameLiftConfig.AuthTokenResult.Value);
+		LogServerParameters(ServerParametersForAnywhere);
+		
+		//  InitSDK will establish a local connection with GameLift's agent to enable further communication.
+		InitSdkOutcome = GameLiftSdkModule->InitSDK(ServerParametersForAnywhere);
+	}
+	else
+	{
+		InitSdkOutcome = GameLiftSdkModule->InitSDK();
+	}
+	
+	if (InitSdkOutcome.IsSuccess())
+	{
+		UE_LOG(LogDS_GameMode, SetColor, TEXT("%s"), COLOR_GREEN);
+		UE_LOG(LogDS_GameMode, Log, TEXT("GameLift InitSDK succeeded!"));
+		UE_LOG(LogDS_GameMode, SetColor, TEXT("%s"), COLOR_NONE);
+	}
+	else
+	{
+		UE_LOG(LogDS_GameMode, SetColor, TEXT("%s"), COLOR_RED);
+		UE_LOG(LogDS_GameMode, Log, TEXT("ERROR: InitSDK failed : ("));
+		FGameLiftError GameLiftError = InitSdkOutcome.GetError();
+		UE_LOG(LogDS_GameMode, Log, TEXT("ERROR: %s"), *GameLiftError.m_errorMessage);
+		UE_LOG(LogDS_GameMode, SetColor, TEXT("%s"), COLOR_NONE);
+		return;
+	}
+		
+	ProcessParameters = MakeShared<FProcessParameters>();
+	//When a game session is created, Amazon GameLift Servers sends an activation request to the game server and passes along the game session object containing game properties and other settings.
+	//Here is where a game server should take action based on the game session object.
+	//Once the game server is ready to receive incoming player connections, it should invoke GameLiftServerAPI.ActivateGameSession()
+	// ReSharper disable once CppPassValueParameterByConstReference - not safe to do with async lambdas
+	ProcessParameters->OnStartGameSession.BindLambda([=](Aws::GameLift::Server::Model::GameSession InGameSession)
+    {
+		const FString GameSessionId = FString(InGameSession.GetGameSessionId());
+        UE_LOG(LogDS_GameMode, Log, TEXT("GameSession Initializing: %s"), *GameSessionId);
+        GameLiftSdkModule->ActivateGameSession();
+    });
+
+    //OnProcessTerminate callback. Amazon GameLift Servers will invoke this callback before shutting down an instance hosting this game server.
+    //It gives this game server a chance to save its state, communicate with services, etc., before being shut down.
+    //In this case, we simply tell Amazon GameLift Servers we are indeed going to shut down.
+	ProcessParameters->OnTerminate.BindLambda([=]()
+    {
+		UE_LOG(LogDS_GameMode, Log, TEXT("Game Server Process is terminating"));
+        // First call ProcessEnding()
+        FGameLiftGenericOutcome processEndingOutcome = GameLiftSdkModule->ProcessEnding();
+        // Then call Destroy() to free the SDK from memory
+        FGameLiftGenericOutcome destroyOutcome = GameLiftSdkModule->Destroy();
+        // Exit the process with success or failure
+        if (processEndingOutcome.IsSuccess() && destroyOutcome.IsSuccess()) {
+            UE_LOG(LogDS_GameMode, Log, TEXT("Server process ending successfully"));
+        }
+        else {
+            if (!processEndingOutcome.IsSuccess()) {
+                const FGameLiftError& error = processEndingOutcome.GetError();
+                UE_LOG(LogDS_GameMode, Error, TEXT("ProcessEnding() failed. Error: %s"),
+                error.m_errorMessage.IsEmpty() ? TEXT("Unknown error") : *error.m_errorMessage);
+            }
+            if (!destroyOutcome.IsSuccess()) {
+                const FGameLiftError& error = destroyOutcome.GetError();
+                UE_LOG(LogDS_GameMode, Error, TEXT("Destroy() failed. Error: %s"),
+                error.m_errorMessage.IsEmpty() ? TEXT("Unknown error") : *error.m_errorMessage);
+            }
+        }
+		GLog->Flush();
+		FGenericPlatformMisc::RequestExit(false);
+    });
+         
+    //This is the Health Check callback.
+    //Amazon GameLift Servers will invoke this callback every 60 seconds or so.
+    //Here, a game server might want to check the health of dependencies and such.
+    //Simply return true if healthy, false otherwise.
+    //The game server has 60 seconds to respond with its health status. Amazon GameLift Servers will default to 'false' if the game server doesn't respond in time.
+    //In this case, we're always healthy!
+	ProcessParameters->OnHealthCheck.BindLambda([]()
+    {
+        UE_LOG(LogDS_GameMode, Log, TEXT("Performing Health Check"));
+        return true;
+    });
+		
+	ProcessParameters->port = GameLiftConfig.ServerPort;
+		
+	TArray<FString> Logfiles;
+	Logfiles.Add(TEXT("FPSTemplate/Saved/Log/server.log"));
+	ProcessParameters->logParameters = Logfiles;
+		
+	UE_LOGFMT(LogDS_GameMode, Log, "Calling Process Ready...");
+	FGameLiftGenericOutcome ProcessReadyOutcome = GameLiftSdkModule->ProcessReady(*ProcessParameters);
+		
+	if (ProcessReadyOutcome.IsSuccess())
+	{
+		UE_LOG(LogDS_GameMode, SetColor, TEXT("%s"), COLOR_GREEN);
+		UE_LOG(LogDS_GameMode, Log, TEXT("Process Ready!"));
+		UE_LOG(LogDS_GameMode, SetColor, TEXT("%s"), COLOR_NONE);
+	}
+	else
+	{
+		UE_LOG(LogDS_GameMode, SetColor, TEXT("%s"), COLOR_RED);
+		UE_LOG(LogDS_GameMode, Log, TEXT("ERROR: Process Ready Failed!"));
+		FGameLiftError ProcessReadyError = ProcessReadyOutcome.GetError();
+		UE_LOG(LogDS_GameMode, Log, TEXT("ERROR: %s"), *ProcessReadyError.m_errorMessage);
+		UE_LOG(LogDS_GameMode, SetColor, TEXT("%s"), COLOR_NONE);
+		return;
+	}
+		
+	UE_LOGFMT(LogDS_GameMode, Log, "InitGameLift completed!");
+	
+#endif
+}
+
+bool ADS_GameMode::GetAnywhereFleetParameters(const FString& CommandLineString)
+{
+	bool bAllAnywhereFleetParametersValid = true;
+	GameLiftConfig.AuthTokenResult = cmdlineparser::GetValueOfToken(CommandLineString, cmdlineparser::details::EAvailableTokens::AuthToken);
+	if (!GameLiftConfig.AuthTokenResult.bIsValid) bAllAnywhereFleetParametersValid = false;
+	
+	GameLiftConfig.FleetIdResult = cmdlineparser::GetValueOfToken(CommandLineString, cmdlineparser::details::EAvailableTokens::FleetId);
+	if (!GameLiftConfig.FleetIdResult.bIsValid) bAllAnywhereFleetParametersValid = false;
+	
+	GameLiftConfig.HostIdResult = cmdlineparser::GetValueOfToken(CommandLineString, cmdlineparser::details::EAvailableTokens::HostId);
+	if (!GameLiftConfig.HostIdResult.bIsValid) bAllAnywhereFleetParametersValid = false;
+
+	GameLiftConfig.WebSocketUrlResult = cmdlineparser::GetValueOfToken(CommandLineString, cmdlineparser::details::EAvailableTokens::WebsocketUrl);
+	if (!GameLiftConfig.WebSocketUrlResult.bIsValid) bAllAnywhereFleetParametersValid = false;
+	
+	return bAllAnywhereFleetParametersValid;
+}
+
+void ADS_GameMode::LogAnywhereFleetParameters()
+{
+		// Lambda for getting the token name from token
+	auto GetTokenName = [](const cmdlineparser::details::FParseResult& Result) -> FString
+	{
+		return cmdlineparser::details::CLI_TOKENS[static_cast<int32>(Result.Token)];
+	};
+	
+	UE_LOGFMT(LogDS_GameMode, Log, "Anywhere Fleet Parameters:");
+	if (GameLiftConfig.AuthTokenResult.bIsValid)
+	{
+		UE_LOGFMT(LogDS_GameMode, Log, "AuthToken: {0}", GetValueOrHash(GameLiftConfig.AuthTokenResult.Value));
+	}
+	else
+	{
+		UE_LOGFMT(
+			LogDS_GameMode, 
+			Error, 
+			"AuthToken: {0}", 
+			FString::Format(
+				*GameLiftConfig.AuthTokenResult.ErrorMessage, 
+				{
+					FStringFormatArg(GetTokenName(GameLiftConfig.AuthTokenResult)), 
+					FStringFormatArg(GetValueOrHash(GameLiftConfig.AuthTokenResult.Value)),
+				}
+			)
+		);
+	}
+	
+	if (GameLiftConfig.FleetIdResult.bIsValid)
+	{
+		UE_LOGFMT(LogDS_GameMode, Log, "FleetId: {0}", GameLiftConfig.FleetIdResult.Value);
+	}
+	else
+	{
+		UE_LOGFMT(
+			LogDS_GameMode, 
+			Error, 
+			"FleetId: {0}", 
+			FString::Format(
+				*GameLiftConfig.FleetIdResult.ErrorMessage, 
+				{
+					FStringFormatArg(GetTokenName(GameLiftConfig.FleetIdResult)), 
+					FStringFormatArg(GameLiftConfig.FleetIdResult.Value)
+				}
+			)
+		);
+	}
+	
+	if (GameLiftConfig.HostIdResult.bIsValid)
+	{
+		UE_LOGFMT(LogDS_GameMode, Log, "HostId: {0}", GameLiftConfig.HostIdResult.Value);
+	}
+	else
+	{
+		UE_LOGFMT(
+			LogDS_GameMode, 
+			Error, 
+			"HostId: {0}", 
+			FString::Format(
+				*GameLiftConfig.HostIdResult.ErrorMessage, 
+				{
+					FStringFormatArg(GetTokenName(GameLiftConfig.HostIdResult)), 
+					FStringFormatArg(GameLiftConfig.HostIdResult.Value)
+				}
+			)
+		);
+	}
+	
+	if (GameLiftConfig.WebSocketUrlResult.bIsValid)
+	{
+		UE_LOGFMT(LogDS_GameMode, Log, "WebSocketUrl: {0}", GameLiftConfig.WebSocketUrlResult.Value);
+	}
+	else
+	{
+		UE_LOGFMT(
+			LogDS_GameMode, 
+			Error, 
+			"WebSocketUrl: {0}", 
+			FString::Format(
+				*GameLiftConfig.WebSocketUrlResult.ErrorMessage, 
+				{
+					FStringFormatArg(GetTokenName(GameLiftConfig.WebSocketUrlResult)), 
+					FStringFormatArg(GameLiftConfig.WebSocketUrlResult.Value)
+				}
+			)
+		);
+	}
+	
+	UE_LOGFMT(LogDS_GameMode, Log, "Server Port: {0}", GameLiftConfig.ServerPort);
+	
+	if (GameLiftConfig.bAllOptionsFound)
+	{
+		UE_LOGFMT(LogDS_GameMode, Log, "Anywhere Fleet Parameters Loaded Successfully....");
+	}
+	else
+	{
+		UE_LOGFMT(LogDS_GameMode, Error, "Anywhere Fleet Parameters Load FAILED....");
+	}
+}
+
+void ADS_GameMode::LogServerParameters(const FServerParameters& InServerParameters)
+{
+	UE_LOGFMT(LogDS_GameMode, Log, ">>>> WebSocket URL: {WebSocketUrl}", InServerParameters.m_webSocketUrl);
+	UE_LOGFMT(LogDS_GameMode, Log, ">>>> Fleet ID: {FleetId}", InServerParameters.m_fleetId);
+	UE_LOGFMT(LogDS_GameMode, Log, ">>>> Process ID: {ProcessId}", InServerParameters.m_processId);
+	UE_LOGFMT(LogDS_GameMode, Log, ">>>> Host ID (Compute Name): {HostId}", InServerParameters.m_hostId);
+	UE_LOGFMT(LogDS_GameMode, Log, ">>>> Auth Token: {AuthToken}", GetValueOrHash(InServerParameters.m_authToken));
+	
+	if (!InServerParameters.m_awsRegion.IsEmpty())
+	{
+		UE_LOGFMT(LogDS_GameMode, Log, ">>>> Aws Region: {AwsRegion}", InServerParameters.m_awsRegion);
+	}
+	
+	if (!InServerParameters.m_accessKey.IsEmpty())
+	{
+		UE_LOGFMT(LogDS_GameMode, Log, ">>>> Access Key: {AccessKey}", GetValueOrHash(InServerParameters.m_accessKey));
+	}
+	
+	if (!InServerParameters.m_secretKey.IsEmpty())
+	{
+		UE_LOGFMT(LogDS_GameMode, Log, ">>>> Secret Key: {SecretKey}", GetValueOrHash(InServerParameters.m_secretKey));
+	}
+	
+	if (!InServerParameters.m_sessionToken.IsEmpty())
+	{
+		UE_LOGFMT(LogDS_GameMode, Log, ">>>> Session Token: {SessionToken}", GetValueOrHash(InServerParameters.m_sessionToken));
+	}
+}
+
+FString ADS_GameMode::GetValueOrHash(const FString& Value)
+{
+#if UE_BUILD_DEBUG || UE_BUILD_DEVELOPMENT
+	return Value;
+#else
+	return TEXT("HASH:") + GetSHA256Hash(Value);
+#endif
+}

Source/DedicatedServers/Private/GameLift/GameLiftClp.cpp

@@ -0,0 +1,100 @@
+#include "GameLift/GameLiftClp.h"
+
+FPortResult cmdlineparser::GetConfiguredOrDefaultPort(const FString& Token)
+{
+	return details::GetConfiguredOrDefaultPort(FCommandLine::Get(), Token);
+}
+
+FPortResult cmdlineparser::GetConfiguredOrDefaultPort(const FString& CommandLine, const FString& Token)
+{
+	return details::GetConfiguredOrDefaultPort(CommandLine, Token);
+}
+
+cmdlineparser::details::FParseResult cmdlineparser::GetValueOfToken(const FString& CommandLine, const details::EAvailableTokens Token)
+{
+	details::FParseResult Result;
+	FString ValueOfToken;
+	Result.Token = Token;
+	
+	ensure(Token != details::EAvailableTokens::Unknown);
+	ensure(Token < details::EAvailableTokens::MaxToken);
+	const bool bTokenFound = FParse::Value(
+		*CommandLine, 
+		*details::EnsureEndsWith(details::CLI_TOKENS[static_cast<int32>(Token)], 
+		TEXT("=")), 
+		ValueOfToken
+		);
+	
+	if (!bTokenFound)
+	{
+		Result.Value = FString();
+		Result.ErrorCode = details::EErrorCodes::TokenNotFound;
+		Result.bIsValid = false;
+	}
+	else
+	{
+		if (ValueOfToken.IsEmpty())
+		{
+			Result.Value = FString();
+			Result.ErrorCode = details::EErrorCodes::ValueEmpty;
+			Result.bIsValid = false;
+		}
+		else
+		{
+			if (details::DoesRegExMatch(ValueOfToken, details::REGEX_PATTERNS[static_cast<int32>(Token)]))
+			{
+				Result.ErrorCode = details::EErrorCodes::NoError;
+            	Result.bIsValid = true;	
+			}
+			else
+			{
+				Result.ErrorCode = details::EErrorCodes::FailedValidation;
+				Result.bIsValid = false;
+			}
+			Result.Value = ValueOfToken;
+		}
+	}
+	
+	ensure(Result.ErrorCode < details::EErrorCodes::MaxCode);
+	FString ErrorMessage = details::ERROR_MESSAGES[static_cast<int32>(Result.ErrorCode)];
+	FString TokenName = details::CLI_TOKENS[static_cast<int32>(Result.Token)];
+	FString Value = Result.Value;
+	Result.ErrorMessage = ErrorMessage;
+	
+	return Result;
+}
+
+
+//  cmdlineparser::Details namespace
+
+FString cmdlineparser::details::EnsureEndsWith(const FString& Token, const TCHAR* Suffix)
+{
+	return Token.EndsWith(Suffix) ? Token : Token + Suffix;
+}
+
+FPortResult cmdlineparser::details::GetConfiguredOrDefaultPort(const FString& CommandLine, const FString& Token)
+{
+	FPortResult PortResult;
+	PortResult.Port = FURL::UrlConfig.DefaultPort;
+
+	if (int32 CliPort; FParse::Value(*CommandLine, *EnsureEndsWith(Token, TEXT("=")), CliPort))
+	{
+		if (CliPort >= details::MIN_PORT && CliPort <= details::MAX_PORT)
+		{
+			PortResult.Port = CliPort;
+			PortResult.bUsedDefaultPort = false;
+			PortResult.WarningMessage = FString();
+			return PortResult;
+		}
+	}
+	PortResult.bUsedDefaultPort = true;
+	PortResult.WarningMessage = FString("Command Line Option for Port is out of ranged...  Using Default Port %s", PortResult.Port);
+	return PortResult;
+}
+
+bool cmdlineparser::details::DoesRegExMatch(const FString& Text, const FString& Pattern)
+{
+	const FRegexPattern RegexPattern(Pattern);
+	FRegexMatcher Matcher(RegexPattern, Text);
+	return Matcher.FindNext();
+}

Source/DedicatedServers/Private/GameLiftClpTypes.cpp

@@ -0,0 +1,34 @@
+#include "GameLiftClpTypes.h"
+
+const TArray<FString>& cmdlineparser::details::ERROR_MESSAGES = []() -> const TArray<FString>&
+{
+	static TArray<FString> Error_Messages;
+	Error_Messages.Add(TEXT("VALID: {0}: {1}"));
+	Error_Messages.Add(TEXT("INVALID TOKEN: [-{0}=] not found in command line arguments"));
+	Error_Messages.Add(TEXT("EMPTY VALUE: [-{0}=] found.  No value assigned"));
+	Error_Messages.Add(TEXT("VALIDATION FAILED: [-{0}=] found....  Value: [{1}]"));
+	return Error_Messages;
+}();
+
+
+const TArray<FString>& cmdlineparser::details::CLI_TOKENS = []() -> const TArray<FString>&
+{
+	static TArray<FString> Cli_Tokens;
+	Cli_Tokens.Add(TEXT("unknown")); // Unknown = 0;
+	Cli_Tokens.Add(TEXT("authtoken"));
+	Cli_Tokens.Add(TEXT("hostid"));
+	Cli_Tokens.Add(TEXT("fleetid"));
+	Cli_Tokens.Add(TEXT("websocketurl"));
+	return Cli_Tokens;
+}();
+
+const TArray<FString>& cmdlineparser::details::REGEX_PATTERNS = []() -> const TArray<FString>&
+{
+	static TArray<FString> Cli_Tokens;
+	Cli_Tokens.Add(TEXT(".*"));  // unknown = 0
+	Cli_Tokens.Add(TEXT("^[a-zA-Z0-9\\-]+$"));
+	Cli_Tokens.Add(TEXT("^[a-zA-Z0-9][a-zA-Z0-9\\-]{0,62}[a-zA-Z0-9]?$"));
+	Cli_Tokens.Add(TEXT("^[a-z]*fleet-[a-zA-Z0-9\\-]+$|^arn:.*:[a-z]*fleet\\/[a-z]*fleet-[a-zA-Z0-9\\-]+$"));
+	Cli_Tokens.Add(TEXT("^wss://[a-z0-9-]+(\\.[a-z0-9-]+)*\\.api\\.amazongamelift\\.com(:[0-9]+)?/?$"));
+	return Cli_Tokens;
+}();

Source/DedicatedServers/Public/Game/DS_GameMode.h

@@ -0,0 +1,50 @@
+// Fill out your copyright notice in the Description page of Project Settings.
+
+#pragma once
+
+#include "CoreMinimal.h"
+#include "DedicatedServers/Public/GameLiftClpTypes.h"
+#include "GameFramework/GameMode.h"
+#include "DS_GameMode.generated.h"
+
+DECLARE_LOG_CATEGORY_EXTERN(LogDS_GameMode, Log, All);
+
+struct FProcessParameters;
+struct FServerParameters;
+
+struct FGameLiftConfig
+{
+	bool bIsAnywhereFleet = false;
+	bool bAllOptionsFound = false;
+	
+	int32 ServerPort = 7777;
+	
+	cmdlineparser::details::FParseResult AuthTokenResult;
+	cmdlineparser::details::FParseResult FleetIdResult;
+	cmdlineparser::details::FParseResult HostIdResult;
+	cmdlineparser::details::FParseResult WebSocketUrlResult;
+};
+
+
+UCLASS()
+class DEDICATEDSERVERS_API ADS_GameMode : public AGameMode
+{
+	GENERATED_BODY()
+	
+protected:
+	virtual void BeginPlay() override;
+	virtual void InitGame(const FString& MapName, const FString& Options, FString& ErrorMessage) override;
+
+private:
+	FGameLiftConfig GameLiftConfig;
+	FString CachedCommandLine;
+	TSharedPtr<FProcessParameters> ProcessParameters;
+	
+	static FString GetSHA256Hash(const FString& InString);
+	void InitGameLift();
+	
+	bool GetAnywhereFleetParameters(const FString& CommandLineString);
+	void LogAnywhereFleetParameters();
+	static void LogServerParameters(const FServerParameters& InServerParameters);
+	static FString GetValueOrHash(const FString& Value);
+};

Source/DedicatedServers/Public/GameLift/GameLiftClp.h

@@ -0,0 +1,30 @@
+#pragma once
+#include "GameLiftClpTypes.h"
+#include "CoreMinimal.h"
+
+struct FPortResult
+{
+	int32 Port;
+	bool bUsedDefaultPort;
+	FString WarningMessage;
+};
+
+namespace cmdlineparser
+{
+	FPortResult GetConfiguredOrDefaultPort(const FString& Token = TEXT("port="));
+	FPortResult GetConfiguredOrDefaultPort(const FString& CommandLine, const FString& Token = TEXT("port="));
+
+	details::FParseResult GetValueOfToken(const FString& CommandLine, const details::EAvailableTokens Token);
+}
+
+namespace cmdlineparser::details
+{
+	inline static constexpr int32 MIN_PORT = 1024;
+	inline static constexpr int32 MAX_PORT = 65535;
+	inline static constexpr const TCHAR* DEFAULT_PORT_TOKEN = TEXT("port=");
+		
+	FString EnsureEndsWith(const FString& Token, const TCHAR* Suffix);
+	FPortResult GetConfiguredOrDefaultPort(const FString& CommandLine, const FString& Token);
+	bool DoesRegExMatch(const FString& Text, const FString& Pattern);
+}
+

Source/DedicatedServers/Public/GameLiftClpTypes.h

@@ -0,0 +1,37 @@
+#pragma once
+
+namespace cmdlineparser::details
+{
+	enum EAvailableTokens
+	{
+		Unknown = 0,
+		AuthToken,
+		HostId,
+		FleetId,
+		WebsocketUrl,
+		MaxToken
+	};
+	
+	enum EErrorCodes
+	{
+		NoError,
+		TokenNotFound,
+		ValueEmpty,
+		FailedValidation,
+		MaxCode
+	};
+	
+	extern const TArray<FString>& ERROR_MESSAGES;
+	extern const TArray<FString>& CLI_TOKENS;
+	extern const TArray<FString>& REGEX_PATTERNS;
+	
+	struct FParseResult
+	{
+		EAvailableTokens Token = EAvailableTokens::Unknown;
+		FString Value = FString();
+		bool bIsValid = false;
+		EErrorCodes ErrorCode = EErrorCodes::TokenNotFound;
+		FString ErrorMessage = FString();
+		
+	};
+}