# Server SDK (Unreal) for Amazon GameLift Servers -- Data types
<a name="integration-server-sdk-unreal-ref-datatypes"></a>

Use the Amazon GameLift Servers server SDK for Unreal reference to integrate your multiplayer game for hosting with Amazon GameLift Servers. For guidance about the integration process, see [Add Amazon GameLift Servers to your game server with the server SDK](gamelift-sdk-server-api.md).

**Note**  
This reference is for an earlier version of the server SDK for Amazon GameLift Servers. For the latest version, see [C\$1\$1 (Unreal) server SDK 5.x for Amazon GameLift Servers -- Data types](integration-server-sdk5-unreal-datatypes.md).

This API is defined in `GameLiftServerSDK.h` and `GameLiftServerSDKModels.h`.

To set up the Unreal Engine plugin and see code examples [Integrate Amazon GameLift Servers into an Unreal Engine project](integration-engines-setup-unreal.md).

[Server SDK (Unreal) for Amazon GameLift Servers -- Actions](integration-server-sdk-unreal-ref-actions.md)

**Topics**
+ [FDescribePlayerSessionsRequest](#integration-server-sdk-unreal-ref-dataypes-playersessions)
+ [FProcessParameters](#integration-server-sdk-unreal-ref-dataypes-process)
+ [FStartMatchBackfillRequest](#integration-server-sdk-unreal-ref-dataypes-startmatchbackfillrequest)
+ [FStopMatchBackfillRequest](#integration-server-sdk-unreal-ref-dataypes-stopmatchbackfillrequest)

## FDescribePlayerSessionsRequest
<a name="integration-server-sdk-unreal-ref-dataypes-playersessions"></a>

This data type is used to specify which player session(s) to retrieve. You can use it as follows: 
+ Provide a PlayerSessionId to request a specific player session.
+ Provide a GameSessionId to request all player sessions in the specified game session.
+ Provide a PlayerId to request all player sessions for the specified player.

For large collections of player sessions, use the pagination parameters to retrieve results in sequential blocks.

### Contents
<a name="integration-server-sdk-unreal-ref-dataypes-playersessions-contents"></a>

**GameSessionId**  
Unique game session identifier. Use this parameter to request all player sessions for the specified game session. Game session ID format is as follows: `arn:aws:gamelift:<region>::gamesession/fleet-<fleet ID>/<ID string>`. The value of <ID string> is either a custom ID string or (if one was specified when the game session was created) a generated string.   
Type: String  
Required: No

**Limit**  
Maximum number of results to return. Use this parameter with *NextToken* to get results as a set of sequential pages. If a player session ID is specified, this parameter is ignored.  
Type: Integer  
Required: No

**NextToken**  
Token indicating the start of the next sequential page of results. Use the token that is returned with a previous call to this action. To specify the start of the result set, do not specify a value. If a player session ID is specified, this parameter is ignored.  
Type: String  
Required: No

**PlayerId**  
Unique identifier for a player. Player IDs are defined by the developer. See [Generate player IDs](player-sessions-player-identifiers.md).  
Type: String  
Required: No

**PlayerSessionId**  
Unique identifier for a player session.  
Type: String  
Required: No

**PlayerSessionStatusFilter**  
Player session status to filter results on. Possible player session statuses include the following:  
+ RESERVED – The player session request has been received, but the player has not yet connected to the server process and/or been validated.
+ ACTIVE – The player has been validated by the server process and is currently connected.
+ COMPLETED – The player connection has been dropped.
+ TIMEDOUT – A player session request was received, but the player did not connect and/or was not validated within the time-out limit (60 seconds).
Type: String  
Required: No

## FProcessParameters
<a name="integration-server-sdk-unreal-ref-dataypes-process"></a>

This data type contains the set of parameters sent to the Amazon GameLift Servers service in a [ProcessReady()](integration-server-sdk-unreal-ref-actions.md#integration-server-sdk-unreal-ref-processready) call.

### Contents
<a name="integration-server-sdk-unreal-ref-dataypes-process-contents"></a>

**port**  
Port number the server process will listen on for new player connections. The value must fall into the port range configured for any fleet deploying this game server build. This port number is included in game session and player session objects, which game sessions use when connecting to a server process.   
Type: Integer   
Required: Yes

**logParameters**  
Object with a list of directory paths to game session log files.   
Type: TArray<FString>  
Required: No

**onStartGameSession**  
Name of callback function that the Amazon GameLift Servers service invokes to activate a new game session. Amazon GameLift Servers calls this function in response to the client request [CreateGameSession](https://docs.aws.amazon.com/gamelift/latest/apireference/API_CreateGameSession.html). The callback function takes a [GameSession](https://docs.aws.amazon.com/gamelift/latest/apireference/API_GameSession.html) object (defined in the *Amazon GameLift Servers Service API Reference*).   
Type: FOnStartGameSession   
Required: Yes

**onProcessTerminate**  
Name of callback function that the Amazon GameLift Servers service invokes to force the server process to shut down. After calling this function, Amazon GameLift Servers waits five minutes for the server process to shut down and respond with a [ProcessEnding()](integration-server-sdk-unreal-ref-actions.md#integration-server-sdk-unreal-ref-processending) call before it shuts down the server process.  
Type: FSimpleDelegate  
Required: No

**onHealthCheck**  
Name of callback function that the Amazon GameLift Servers service invokes to request a health status report from the server process. Amazon GameLift Servers calls this function every 60 seconds. After calling this function Amazon GameLift Servers waits 60 seconds for a response, and if none is received. records the server process as unhealthy.  
Type: FOnHealthCheck  
Required: No

**onUpdateGameSession**  
Name of callback function that the Amazon GameLift Servers service invokes to pass an updated game session object to the server process. Amazon GameLift Servers calls this function when a [ match backfill](https://docs.aws.amazon.com/gamelift/latest/flexmatchguide/match-backfill.html) request has been processed in order to provide updated matchmaker data. It passes a [GameSession](https://docs.aws.amazon.com/gamelift/latest/apireference/API_GameSession.html) object, a status update (`updateReason`), and the match backfill ticket ID.   
Type: FOnUpdateGameSession   
Required: No

## FStartMatchBackfillRequest
<a name="integration-server-sdk-unreal-ref-dataypes-startmatchbackfillrequest"></a>

This data type is used to send a matchmaking backfill request. The information is communicated to the Amazon GameLift Servers service in a [StartMatchBackfill()](integration-server-sdk-unreal-ref-actions.md#integration-server-sdk-unreal-ref-startmatchbackfill) call.

### Contents
<a name="integration-server-sdk-unreal-ref-dataypes-startbackfill-contents"></a>

**GameSessionArn**  
 Unique game session identifier. The API action [GetGameSessionId()](integration-server-sdk-unreal-ref-actions.md#integration-server-sdk-unreal-ref-getgamesessionid) returns the identifier in ARN format.  
Type: FString  
Required: Yes

**MatchmakingConfigurationArn**  
Unique identifier, in the form of an ARN, for the matchmaker to use for this request. To find the matchmaker that was used to create the original game session, look in the game session object, in the matchmaker data property. Learn more about matchmaker data in [ Work with matchmaker data](https://docs.aws.amazon.com/gamelift/latest/flexmatchguide/match-server.html#match-server-data).   
Type: FString  
Required: Yes

**Players**  
A set of data representing all players who are currently in the game session. The matchmaker uses this information to search for new players who are good matches for the current players. See the *Amazon GameLift Servers API Reference Guide* for a description of the Player object format. To find player attributes, IDs, and team assignments, look in the game session object, in the matchmaker data property. If latency is used by the matchmaker, gather updated latency for the current region and include it in each player's data.   
Type: TArray[<FPlayer>](https://docs.aws.amazon.com/gamelift/latest/apireference/API_Player.html)  
Required: Yes

**TicketId**  
Unique identifier for a matchmaking or match backfill request ticket. If no value is provided here, Amazon GameLift Servers will generate one in the form of a UUID. Use this identifier to track the match backfill ticket status or cancel the request if needed.   
Type: FString  
Required: No

## FStopMatchBackfillRequest
<a name="integration-server-sdk-unreal-ref-dataypes-stopmatchbackfillrequest"></a>

This data type is used to cancel a matchmaking backfill request. The information is communicated to the Amazon GameLift Servers service in a [StopMatchBackfill()](integration-server-sdk-unreal-ref-actions.md#integration-server-sdk-unreal-ref-stopmatchbackfill) call.

### Contents
<a name="integration-server-sdk-unreal-ref-dataypes-stopbackfill-contents"></a>

**GameSessionArn**  
Unique game session identifier associated with the request being canceled.   
Type: FString  
Required: Yes

**MatchmakingConfigurationArn**  
Unique identifier of the matchmaker this request was sent to.   
Type: FString  
Required: Yes

**TicketId**  
Unique identifier of the backfill request ticket to be canceled.  
Type: FString  
Required: Yes