Install localstack

pip install localstack or pip3 install localstack

Start localstack

localstack start

Run

1. aws_init.sh - creates s3 buckets and creats lambda execution role with the right policy

2. create_lambda.sh - creates lambda function with simple code that outputs the key of the s3 file created event

3. configure_s3_to_publish_event.sh - configure event for s3 object-creation which will trigger a lambda

4. aws logs tail "/aws/lambda/MyLambdaFn" --endpoint-url http://localhost:4566 --follow - follow lambda logs for console.log statements

5. aws s3 cp test.txt s3://source-bucket/test.txt --endpoint-url http://localhost:4566 - copy local file to s3 bucket

AWS reference:

https://docs.aws.amazon.com/lambda/latest/dg/nodejs-handler.html