Create an AWS Cloudfront invalidation in a Grunt task

cloudfront-invalidation-grunt.js

grunt.registerTask('cloudfront:invalidate', 'invalidate lib on cloudfront', function() {

  var finished = this.async(),
      aws = require('aws-sdk'),
      path = '/libs/ll.sdk-' + sdk_version + '.js'
  ;

  // set aws keys & region from config
  aws.config.update({
    accessKeyId: config.aws.accessKeyId,
    secretAccessKey: config.aws.secretAccessKey,
    // CloudFront doesn't use regions, but unless this is set to us-east-1 
    // the API will cry and refuse to do anything
    region: 'us-east-1'
  });

  var cloudfront = new aws.CloudFront({ apiVersion: '2013-05-12' });

  cloudfront.createInvalidation({
    DistributionId: config.aws_cloudfront_distribution,
    InvalidationBatch: {
      Paths: {
        Quantity: 1,
        Items: [
          path
        ]
      },
      CallerReference: new Date().getTime().toString()
    }
  }, function(err, data) {
    if (err) {
      grunt.log.error('Failed');
      grunt.log.errorlns(err.message);
      finished();
    } else {
      grunt.log.ok('Invalidation created (id: ' + data.Id + ')');
      finished();
    }
  });
});