Where can I find the AWS_PROXY Velocity Template used by the API Gateway Service?

Hey noink! I'd like to know your use case, what you can't accomplish using AWS_PROXY integration response (https://docs.aws.amazon.com/apigateway/latest/developerguide/api-gateway-integration-settings-integration-response.html). A quote from a friend: "Using non-proxy integration for Lambda is not recommended since the VTL does not have a good experience and template transformation can be impacted during Garbage Collector pressure."

I recently had to create an application that served both an XML and CSV response. I would have had no issue using the standard proxy input, but I needed a non-JSON response.

Wouldn't the proxy integration, returning the file as binary in base64, and setting the right header (application/xml or text/csv), work for your use case? Here is an example: https://docs.aws.amazon.com/apigateway/latest/developerguide/lambda-proxy-binary-media.html. The requester will not receive the JSON, but the content that was binary encoded in base64.