API Gateway with custom authorizer lambda wont support signature validation

AWS API Gateway with custom authorizer
AWS API Gateway with custom authorizer


If you have an API Gateway with a custom authorizer and you want to validate the signature of the incoming request(POST, PUT or calls with payload) then AWS currently does not support this. Usually the signature validation logic will need the request payload. 

But AWS API Gateway does not forward the request body to the authorizer lambda. You may try to hack(stage variables etc) this but there is no real way to do this as of now.