Scheduled Start/Stop of EC2 Instances using Lambda and Serverless (Extra)

handler.js

'use strict';

const AWS = require('aws-sdk');

module.exports.stateChange = (event, context, callback) => {
  const { state, id, region } = event;

  const ec2 = new AWS.EC2({ region });

  ec2[`${state}Instances`]({ InstanceIds: [id] }).promise()
    .then(() => callback(null, `Successfully ${state} ${id}`))
    .catch(err => callback(err));
};

instances.js

'use strict';

const instances = [
  {
    id: 'i-11111111111111',
    region: 'eu-west-1',
    start: '30 6 * * ? *',
    stop: '30 18 * * ? *',
  },
  {
    id: 'i-00000000000000',
    region: 'eu-west-1',
    start: '30 8 * * ? *',
    stop: '30 16 * * ? *',
  },
];

// --

const start = ({id, region, start}) =>
  ({ schedule: { rate: `cron(${start})`, input: { state: 'start', id, region } } });

const stop = ({id, region, stop}) =>
  ({ schedule: { rate: `cron(${stop})`, input: { state: 'stop', id, region } } });

module.exports.schedule = () =>
  instances.reduce((acc, instance) => [ ...acc, start(instance), stop(instance) ], []);
 

serverless.yml

service: start-stop-ec2-instances

provider:
  name: aws
  runtime: nodejs6.10
  stage: prod
  region: eu-west-1
  iamRoleStatements:
    - Effect: "Allow"
      Action:
        - "ec2:StartInstances"
        - "ec2:StopInstances"
      Resource: "*"

functions:
  stateChange:
    handler: handler.stateChange
    events: ${file(./instances.js):schedule}