Using Lambda with Amazon MSK - AWS Lambda
Example event

Using Lambda with Amazon MSK

Note

If you want to send data to a target other than a Lambda function or enrich the data before sending it, see Amazon EventBridge Pipes.

Amazon Managed Streaming for Apache Kafka (Amazon MSK) is a fully managed service that you can use to build and run applications that use Apache Kafka to process streaming data. Amazon MSK simplifies the setup, scaling, and management of clusters running Kafka. Amazon MSK also makes it easier to configure your application for multiple Availability Zones and for security with AWS Identity and Access Management (IAM). Amazon MSK supports multiple open-source versions of Kafka.

Amazon MSK as an event source operates similarly to using Amazon Simple Queue Service (Amazon SQS) or Amazon Kinesis. Lambda internally polls for new messages from the event source and then synchronously invokes the target Lambda function. Lambda reads the messages in batches and provides these to your function as an event payload. The maximum batch size is configurable (the default is 100 messages). For more information, see Batching behavior.

By default, Lambda autoscales the number of event pollers for your Amazon MSK event source mapping. To optimize the throughput of your Amazon MSK event source mapping, configure provisioned mode. In provisioned mode, you can define the minimum and maximum number of event pollers allocated to your event source mapping. This can improve the ability of your event source mapping to handle unexpected message spikes. For more information, see provisioned mode.

Warning

Lambda event source mappings process each event at least once, and duplicate processing of records can occur. To avoid potential issues related to duplicate events, we strongly recommend that you make your function code idempotent. To learn more, see How do I make my Lambda function idempotent in the AWS Knowledge Center.

For an example of how to configure Amazon MSK as an event source, see Using Amazon MSK as an event source for AWS Lambda on the AWS Compute Blog. For a complete tutorial, see Amazon MSK Lambda Integration in the Amazon MSK Labs.

Topics

Example event

Lambda sends the batch of messages in the event parameter when it invokes your function. The event payload contains an array of messages. Each array item contains details of the Amazon MSK topic and partition identifier, together with a timestamp and a base64-encoded message.

{
   "eventSource":"aws:kafka",
   "eventSourceArn":"arn:aws:kafka:us-east-1:123456789012:cluster/vpc-2priv-2pub/751d2973-a626-431c-9d4e-d7975eb44dd7-2",
   "bootstrapServers":"b-2.demo-cluster-1.a1bcde.c1.kafka.us-east-1.amazonaws.com:9092,b-1.demo-cluster-1.a1bcde.c1.kafka.us-east-1.amazonaws.com:9092",
   "records":{
      "mytopic-0":[
         {
            "topic":"mytopic",
            "partition":0,
            "offset":15,
            "timestamp":1545084650987,
            "timestampType":"CREATE_TIME",
            "key":"abcDEFghiJKLmnoPQRstuVWXyz1234==",
            "value":"SGVsbG8sIHRoaXMgaXMgYSB0ZXN0Lg==",
            "headers":[
               {
                  "headerKey":[
                     104,
                     101,
                     97,
                     100,
                     101,
                     114,
                     86,
                     97,
                     108,
                     117,
                     101
                  ]
               }
            ]
         }
      ]
   }
}