Currently, for triggering a lambda function in response to a CloudWatch alarm, I need to route the alarm via SNS, like this:
AWS CloudWatch Alarm --> Send to a topic in SNS --> SNS topic triggers the lambda function So, is there a way I can do it directly, without SNS in the middle? [Reason: Less touch points and a bit of cost optimization].
CloudWatch events trigger lambda but there is no way I can trigger alarms via it. The only options available in CloudWatch events for SQS are:
As far as I know, it is not possible. The the offcial AWS Lambda documentation says it support CloudWatch Events, but no mention of CloudWatch Alarms (and CW Events != CW Alarms)
What you are currently doing, sending the alarms on a SNS and using listening on a topic seems the way to go. In fact, CloudWatch Alarms only outputs to SNS so far.
It is possible to trigger Lambda function from CloudWatch alarm, by using EventBridge https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/cloudwatch-and-eventbridge.html
