How to get the Cognito Identity id in AWS Lambda

Question

How can I get the identity id of the user (logged in by AWS Cognito) that invoked an AWS Lambda function? Do I have to use the SDK on the Lambda function to get the identity

Answer 1

If you go through API Gateway, you can pass the cognito id (as well as the user arn and other useful information) to Lambda. This solved the issue for me.

http://docs.aws.amazon.com/apigateway/latest/developerguide/api-gateway-mapping-template-reference.html