Services or capabilities described in Amazon Web Services documentation might vary by Region. To see the differences applicable to the China Regions, see Getting Started with Amazon Web Services in China (PDF).

Set up FlexMatch event notifications

You can use event notifications to track the status of individual matchmaking requests. All games in production, or in pre-production with high-volume matchmaking activity should use event notifications.

There are two options for setting up event notifications.

For a list of the FlexMatch events that Amazon GameLift emits, see FlexMatch matchmaking events.

Set up EventBridge events

Amazon GameLift automatically posts all matchmaking events to Amazon EventBridge. With EventBridge, you can set up rules to have matchmaking events routed to targets for processing. For example, you can set a rule to route the event "PotentialMatchCreated" to an Amazon Lambda function that handles player acceptances. For more information, see What is Amazon EventBridge?

Set up an Amazon SNS topic

You can have Amazon GameLift publish all events that a FlexMatch matchmaker generates to an Amazon SNS topic.

Set up an SNS topic with server-side encryption

You can use server-side encryption (SSE) to store sensitive data in encrypted topics. SSE protects the contents of messages in Amazon SNS topics using keys managed in Amazon Key Management Service (Amazon KMS). For more information about server-side encryption with Amazon SNS, see Encryption at rest in the Amazon Simple Notification Service Developer Guide.

To set up an SNS topic with server-side encryption, review the following topics:

When creating your KMS key, use the following KMS key policy:

{ 
  "Effect": "Allow", 
  "Principal": { 
    "Service": "gamelift.amazonaws.com" 
  },
  "Action": [
      "kms:Decrypt",
      "kms:GenerateDataKey"
  ],
  "Resource": "*",
  "Condition": {
      "ArnLike": { 
        "aws:SourceArn": "arn:aws:gamelift:your_region:your_account:matchmakingconfiguration/your_configuration_name" 
      },
      "StringEquals": { 
        "kms:EncryptionContext:aws:sns:topicArn": "arn:aws:sns:your_region:your_account:your_sns_topic_name" 
      }
  }
}

Configure a topic subscription to invoke a Lambda function

You can invoke a Lambda function using event notifications published to your Amazon SNS topic. When configuring the matchmaker, be sure to set the notification target to your SNS topic's ARN.

The following Amazon CloudFormation template configures a subscription to an SNS topic named MyFlexMatchEventTopic to invoke a Lambda function named FlexMatchEventHandlerLambdaFunction. The template creates an IAM permissions policy that allows Amazon GameLift to write to the SNS topic. The template then adds permissions for the SNS topic to invoke the Lambda function.

FlexMatchEventTopic:
  Type: "AWS::SNS::Topic"
  Properties:
    KmsMasterKeyId: alias/aws/sns #Enables server-side encryption on the topic using an Amazon managed key 
    Subscription:
      - Endpoint: !GetAtt FlexMatchEventHandlerLambdaFunction.Arn
        Protocol: lambda
    TopicName: MyFlexMatchEventTopic

FlexMatchEventTopicPolicy:
  Type: "AWS::SNS::TopicPolicy"
  DependsOn: FlexMatchEventTopic
  Properties:
    PolicyDocument:
      Version: "2012-10-17"
      Statement:
        - Effect: Allow
          Principal:
            Service: gamelift.amazonaws.com
          Action:
            - "sns:Publish"
          Resource: !Ref FlexMatchEventTopic
    Topics:
      - Ref: FlexMatchEventTopic

FlexMatchEventHandlerLambdaPermission:
  Type: "AWS::Lambda::Permission"
  Properties:
    Action: "lambda:InvokeFunction"
    FunctionName: !Ref FlexMatchEventHandlerLambdaFunction
    Principal: sns.amazonaws.com
    SourceArn: !Ref FlexMatchEventTopic