AWS Lambda function to reboot EC2 instances. Ruby 2.5 Runtime. Execution Role needs: Allow: ec2:RebootInstances, Allow: ec2:DescribeInstances, Allow: ec2:DescribeTags

lambda_function.rb

require 'aws-sdk-ec2'
 
# You can customize the lambda function in AWS console to use ENV variables or to receive
# the region, tags or any identification for your EC2 instances in the event message.
def lambda_handler(event:, context:)
  ec2 = Aws::EC2::Resource.new(region: 'us-east-2')
  instances = ec2.instances(filters: [
      {
        name: "tag:Role",
        values: ["API"],
      },
      {
        name: "tag:Env",
        values: ["Production"],
      }
   ])
  instances.batch_reboot
  "Restarting: #{instances.map(&:id).join(',')}..."
end