バックアップ用のAMIを取得する(lambda向け)

create-ami.js

const AWS = require('aws-sdk');
AWS.config.region = 'ap-northeast-1';
AWS.config.setPromisesDependency(Promise);

const ec2 = new AWS.EC2();

exports.handler = function (evt, context, cb) {
  if (!evt.date) {
    return cb(new Error('please set "date" to a first argument.'));
  }

  ec2.describeTags({
    Filters: [{
      Name: "tag:backupDays",
      Values: [evt.date + '']
    }]
  }).promise().then((data) => {
    if (!data.Tags.length) { return []; }
    const today = getToday();

    const tasks = data.Tags.map((tag) => {
      const id = tag.ResourceId;

      return ec2.createImage({
        InstanceId: id,
        Name: `backup_for_${id}_${today}`,
        Description: `backup for ${id} at ${today}`,
        DryRun: false,
        NoReboot: true,
      }).promise();
    });

    return Promise.all(tasks);
  }).then((amis) => {
    const ids = amis.map((ami) => { return ami.ImageId; });

    return ec2.createTags({
      Resources: ids,
      Tags: [
        {
          Key: 'isBackupByBatch',
          Value: "true"
        }
      ]
    }).promise();
  }).then((data) => {
    cb(null, data);
  }).catch(cb);
};


/**
 * 現在の日付を返す
 *
 * @return {String} YYYY-M-D形式
 */
function getToday() {
  const today = new Date();
  return `${today.getYear() + 1900}-${today.getMonth() + 1}-${today.getDate()}`;
}