AWS Lambda & S3 Integration | Automatic trigger Amazon Lambda function on s3 event

CDK reference for triggering lambda on S3 events.

CDK reference for creating a lambda function.

Write lambda function handler in Kotlin - Sample.

Sample S3 notification which will be received as event parameter in the handler. Read the event as per use case and perform the required actions in the handler.

You will also need to create the required IAM roles / policies. This is an example of doing it via the console. You can refer cdk documentation to create these roles via code.