Amazon GameLift
Developer Guide (Version )

Add Amazon GameLift to an Unreal Engine Game Server Project

This topic helps you set up and use the Amazon GameLift Server SDK plugin for Unreal Engine in your game server projects. If you're unsure whether Amazon GameLift supports the operating systems you're using, see For Game Servers.

Set Up the Unreal Engine Server SDK Plugin

Follow these steps to get the Amazon GameLift Server SDK plugin for Unreal Engine ready for your game server projects.

To set up the Amazon GameLift SDK plugin for Unreal Engine

  1. Download the Amazon GameLift Server SDK. To verify that your game system requirements are supported, see Amazon GameLift SDKs.

  2. Build the C++ Server SDK libraries for Unreal. The SDK download contains the source code for C++ (see GameLift_<release date>\GameLift-SDK-Release-<version>\GameLift-cpp-ServerSDK-<version>). Check the README file in this directory for minimum requirements before building the SDK.

    To build the SDK libraries, go to the directory GameLift-cpp-ServerSDK-<version> and compile with the flag -DBUILD_FOR_UNREAL set to true. The following instructions show how to compile using cmake.

    For Linux users:

    mkdir out cd out cmake -DBUILD_FOR_UNREAL=1 .. make

    The following binary files are generated:

    • out/prefix/lib/

    For Windows users:

    mkdir out cd out cmake -G "Visual Studio 14 2015 Win64" -DBUILD_FOR_UNREAL=1 .. msbuild ALL_BUILD.vcxproj /p:Configuration=Release

    The following binary files are generated:

    • out\prefix\bin\aws-cpp-sdk-gamelift-server.dll

    • out\prefix\lib\aws-cpp-sdk-gamelift-server.lib

    For more details on building the C++ SDK, including minimum requirements and build options, see the file included in the download.

  3. Add the binaries to the Amazon GameLift plugin files. Copy the new binary files into the ThirdParty directory of the Unreal plugin, with the following paths:

    In Linux use these paths:

    • ThirdParty/GameLiftServerSDK/Linux/x86_64-unknown-linux-gnu/

    In Windows use these paths:

    • ThirdParty\GameLiftServerSDK\Win64\aws-cpp-sdk-gamelift-server.dll

    • ThirdParty\GameLiftServerSDK\Win64\aws-cpp-sdk-gamelift-server.lib

  4. Import the Amazon GameLift plugin into a project. Although you have many ways to import a plugin into Unreal Engine, the following method does not require the Unreal Editor.

    1. Add the plugin to your game project. The plugin files must contain everything in the plugin's GameLiftServerSDK directory, including the generated binary files.

    2. Add the plugin to your game's .uproject file:

      "Plugins": [ { "Name": "GameLiftServerSDK", "Enabled": true } ]
    3. Add the plugin as a dependency to your game's ModuleRules:

      using UnrealBuildTool; public class MyAwesomeGame : ModuleRules { public MyAwesomeGame(TargetInfo Target) { PublicDependencyModuleNames.AddRange(new string[] { "Core", "CoreUObject", "Engine", "InputCore", "GameLiftServerSDK" }); } }

Add Amazon GameLift Code

For more information on adding Amazon GameLift functionality, see these topics:

When adding Amazon GameLift-specific code to your Unreal Engine game project, enclose the code using the preprocessor flag WITH_GAMELIFT=1. This flag ensures that only server builds invoke the Amazon GameLift backplane API and allows you to write code that is executed correctly regardless of the build target type you might produce with it.

Code enclosed with the WITH_GAMELIFT=1 flag is only processed if the following are true:

  • The plugin found the Amazon GameLiftserver SDK binary files.

  • The build is a game server: Target.Type == TargetRules.TargetType.Server

The following code snippet illustrates how to initialize an Unreal Engine game server with Amazon GameLift.

// "GameLiftFPS" is a sample game name, replace with file names from your own game project #include "GameLiftFPS.h" #include "Engine.h" #include "EngineGlobals.h" #include "GameLiftFPSGameMode.h" #include "GameLiftFPSHUD.h" #include "GameLiftFPSCharacter.h" #include "GameLiftServerSDK.h" AGameLiftFPSGameMode::AGameLiftFPSGameMode() : Super() { //Let's run this code only if GAMELIFT is enabled. Only with Server targets! #if WITH_GAMELIFT //Getting the module first. FGameLiftServerSDKModule* gameLiftSdkModule = &FModuleManager::LoadModuleChecked<FGameLiftServerSDKModule>(FName("GameLiftServerSDK")); //InitSDK establishes a local connection with GameLift's agent to enable further communication. gameLiftSdkModule->InitSDK(); //When a game session is created, GameLift 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() auto onGameSession = [=](Aws::GameLift::Server::Model::GameSession gameSession) { gameLiftSdkModule->ActivateGameSession(); }; FProcessParameters* params = new FProcessParameters(); params->OnStartGameSession.BindLambda(onGameSession); //OnProcessTerminate callback. GameLift invokes 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 GameLift we are indeed going to shut down. params->OnTerminate.BindLambda([=](){gameLiftSdkModule->ProcessEnding();}); //This is the HealthCheck callback. //GameLift invokes 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. GameLift defaults to 'false' if the game server doesn't respond in time. //In this case, we're always healthy! params->OnHealthCheck.BindLambda([](){return true; }); //Set the port that your game service is listening on for incoming player connections (hard-coded here for simplicity) params->port = 7777; //Here, the game server tells GameLift what set of files to upload when the game session ends. //GameLift uploads everything specified here for the developers to fetch later. TArray<FString> logfiles; logfiles.Add(TEXT("aLogFile.txt")); params->logParameters = logfiles; //Calling ProcessReady tells GameLift this game server is ready to receive incoming game sessions! gameLiftSdkModule->ProcessReady(*params); #endif }