I created an AWS Lambda function that:
Locally, using Node, I can successfully connect to
I find it's either you open your Redshift security group public to all sources, or none. Because a Lambda function isn't running on a fixed address or even a fixed range of IP addresses, which is completely transparent to users (AKA server-less).
I just saw Amazon announced the new Lambda feature to support VPC yesterday. I guess if we can run a Redshift cluster in a VPC, this could solve the problem.