How to add more details on a AWS SAM template for my api

Question

I'm new to AWS serverless world and also to SAM. I just did a small bot that is actually totally functional but when I start doing a SAM Template to define it I have a doubt that I haven't been able to figure out. I have a api gateway, and it have an specific mapping template. I need that the sam template include this, and it doesn't, check the template:

 AWSTemplateFormatVersion: '2010-09-09' Transform: 'AWS::Serverless-2016-10-31' Description: An AWS Serverless Specification template describing your function. Resources: certainty: Type: 'AWS::Serverless::Function' Properties: Handler: index.handler Runtime: nodejs8.10 CodeUri: ./certainty-function Description: >- This lambda monitors the ssl certificates expirations and communite with slack. MemorySize: 128 Timeout: 20 Role: 'arn:aws:iam::116738426468:role/ssl_cert_alerter' Events: Schedule1: Type: Schedule Properties: Schedule: rate(1 day) Api1: Type: Api Properties: Path: / Method: POST certaintyassistant: Type: 'AWS::Serverless::Function' Properties: Handler: index.handler Runtime: nodejs8.10 CodeUri: ./certainty-assistant-function Description: >- This lambda invoke Certainty and answer to the slack user. MemorySize: 1152 Timeout: 300 Role: 'arn:aws:iam::116738426468:role/ssl_cert_alerter' Events: Api1: Type: Api Properties: Path: /show-all Method: POST Environment: Variables: SLACK_TOKEN: oGprdUe0br93yH62fuezDHQh 

So after saying this, I want to show how I manage the mapping on the api:

 ## designed just for post format. { #foreach( $token in $input.path('$').split('&') ) #set( $keyVal = $token.split('=') ) #set( $keyValSize = $keyVal.size() ) #if( $keyValSize >= 1 ) #set( $key = $util.urlDecode($keyVal[0]) ) #if( $keyValSize >= 2 ) #set( $val = $util.urlDecode($keyVal[1]) ) #else #set( $val = '' ) #end "$key": "$val"#if($foreach.hasNext),#end #end #end } 

And I need to figure how to detail that mapping for my template to create it when it update the stack on CloudFormation.

Maybe if I'm having a bad approach, please show me how it should be done.

Answer 1

To achieve that you'll have to add an AWS::Serverless::Api resource to your SAM template and use its Definition -property to define your API as OpenAPI-template, where you can include your request and response mappings.

The git-repository of AWS SAM contains an example how to include inline swagger into your template and the documentation of API Gateway contains information about a set of OpenAPI extensions used to define details like requestTemplates .