cfn-alarms-cli

Tool for creating CloudFormation alarms based on the resources in a CloudFormation/SAM stack template.

Why?

This is an effort to create a baseline of CloudFormation alarms for CloudFormation stacks. The intention is to save developers' time by providing a fast way to create alarms that follow some good practices so they can focus on building features rather than managing monitors.

Demo

Usage:

1. Point the tool at your CloudFormation or SAM template.

cfn-alarms -t <template.yaml>

The tool will list the resource types that it has alarm templates for. It currently supports the following types, with more to follow:

• AWS::Lambda::Function / AWS::Serverless::Function
  • Error rate and error count
• AWS::DynamoDB::Table / AWS::Serverless::SimpleTable
  • User and system errors count
• AWS::ApiGateway::RestApi / AWS::Serverless::Api
  • Apdex score, HTTP error rate and error count
• AWS::StepFunctions::StateMachine / AWS::Serverless::StateMachine
  • Success rate < 99%
• AWS::SQS::Queue
  • Queue depth

? Select resource types (Press <space> to select, <a> to toggle all, <i> to invert selection)
❯◯ AWS::Serverless::Function
 ◯ AWS::DynamoDB::Table
 ◯ AWS::SQS::Queue
 ◯ AWS::Serverless::SimpleTable
 ◯ AWS::ApiGateway::RestApi 

Select the resources you want to create alarms for.

2. Select the alarms you want to create.

The tool will list the available alarms for each resource type selected in step one. Select the ones you want to create.

? Select alarm(s) 
 ◯ ErrorsGreaterThanZero
❯◉ ErrorRate

3. Select how you want to be alerted.

? Select notification channel (Use arrow keys)
  None 
❯ Slack

If you select 'None' then you can build your own custom notification channel based on the alarm state change EventBridge events.

Selecting Slack will generate resources and permissions for EventBridge API Destinations targeting https://slack.com/api/chat.postMessage. You will need to create a Slack app and add its OAUTH2 token to SecretsManager under the key cfn-alarms-cli/slack-token like this:

{
  "Value": "xoxb-1234567890-your-slack-token-321"
}

Example output:

4. Select the desired output format.

? Select output (Use arrow keys)
❯ Write to separate file (monitoring.yaml) 
  Append to template.yaml 

Selecting 'Write to separate file' will write the generated alarms to a file called monitoring.yaml in the current directory which will be included in the main template via Fn::Transform

Selecting 'Append to template.yaml' will append the generated alarms to the main template.