Cfnresponse

Cfnresponse helps with writing Custom CloudFormation resources. The main method is send_response, which builds the response that is sent back to CloudFormation service from the Lambda function.

Installation

Add this line to your application’s Gemfile:

ruby gem 'cfnresponse'

And then execute:

$ bundle

Or install it yourself as:

$ gem install cfnresponse

Example Usage

```ruby require “cfnresponse” include Cfnresponse

def lambda_handler(event:, context:) print(“Received event: “ + json_pretty(event))

case event[‘RequestType’] when “Create” # create logic send_response(event, context, SUCCESS) when “Update” # update logic send_response(event, context, SUCCESS) when “Delete” # delete logic send_response(event, context, SUCCESS) end

sleep 10 # a little time for logs to be sent to CloudWatch

We rescue all exceptions and send a message to CloudFormation so we don’t have to

# wait for over an hour for the stack operation to timeout and rollback. rescue Exception => e puts e.message puts e.backtrace sleep 10 # a little time for logs to be sent to CloudWatch send_response(event, context, “FAILED”) end ```

• Cfnresponse code