How to do it...

1. Create the project from the following template:

$ sls create --template-url https://github.com/danteinc/js-cloud-native-cookbook/tree/master/ch2/materialized-view-s3 --path cncb-materialized-view-s3

2. Navigate to the cncb-materialized-view-s3 directory with cd cncb-materialized-view-s3.
3. Review the file named serverless.yml with the following content:

service: cncb-materialized-view-s3

provider:
  name: aws
  runtime: nodejs8.10
  iamRoleStatements:
    ...

functions:
  listener:
    handler: handler.listener
    events:
      - stream:
          type: kinesis
          arn: ${cf:cncb-event-stream-${opt:stage}.streamArn}
          ...
    environment:
      BUCKET_NAME:
        Ref: Bucket

resources:
  Resources:
    Bucket:
      Type: AWS::S3::Bucket

  Outputs:
    BucketName:
      Value:
        Ref: Bucket
    BucketDomainName:
      Value:
        Fn::GetAtt: [ Bucket, DomainName ]

4. Review the file named handler.js with the following content:

module.exports.listener = (event, context, cb) => {
  _(event.Records)
    .map(recordToEvent)
    .filter(forThingCreated)
    .map(toThing)
    .flatMap(put)
    .collect()
    .toCallback(cb);
};

...
const forThingCreated = e => e.type === 'thing-created';

const toThing = event => ({
  id: event.thing.new.id,
  name: event.thing.new.name,
  description: event.thing.new.description,
  asOf: event.timestamp,
});

const put = thing => {
  const params = {
    Bucket: process.env.BUCKET_NAME,
    Key: `things/${thing.id}`,
    ACL: 'public-read',
    ContentType: 'application/json',
    CacheControl: 'max-age=300',
    Body: JSON.stringify(thing),
  };

  const s3 = new aws.S3();
  return _(s3.putObject(params).promise());
};

5. Install the dependencies with npm install.
6. Run the tests with npm test -- -s $MY_STAGE.
   
7. Review the contents generated in the .serverless directory.
8. Deploy the stack:

$ npm run dp:lcl -- -s $MY_STAGE

> cncb-materialized-view-s3@1.0.0 dp:lcl <path-to-your-workspace>/cncb-materialized-view-s3
> sls deploy -r us-east-1 "-s" "john"

Serverless: Packaging service...
...
Serverless: Stack update finished...
...
functions:
  listener: cncb-materialized-view-s3-john-listener

Stack Outputs
BucketName: cncb-materialized-view-s3-john-bucket-1pp3d4c2z99kt
BucketDomainName: cncb-materialized-view-s3-john-bucket-1pp3d4c2z99kt.s3.amazonaws.com
...

9. Review the stack, function, and bucket from the AWS Console.
10. Publish an event from a separate Terminal with the following commands:

$ cd <path-to-your-workspace>/cncb-event-stream
$ sls invoke -r us-east-1 -f publish -s $MY_STAGE -d '{"type":"thing-created","thing":{"new":{"name":"thing three","id":"33333333-3333-3333-3333-333333333333"}}}'
{
    "ShardId": "shardId-000000000000",
    "SequenceNumber": "49583553996455686705785668952918833314346020725338406914"
}

11. Take a look at the logs:

$ sls logs -f listener -r us-east-1 -s $MY_STAGE
START ...
2018-04-17 22:49:20 ... event: {"Records":[...]}
2018-04-17 22:49:20 ... {"type":"thing-created","thing":{"new":{"name":"thing three","id":"33333333-3333-3333-3333-333333333333"}},"id":"16a7b930-42b3-11e8-8700-a918e007d88a","partitionKey":"3de89e9d-c48d-4255-84fc-6c1b7e3f8b90","timestamp":1524019758148,"tags":{"region":"us-east-1"}}
2018-04-17 22:49:20 ... params: {"Bucket":"cncb-materialized-view-s3-john-bucket-1pp3d4c2z99kt","Key":"things/33333333-3333-3333-3333-333333333333","ACL":"public-read","ContentType":"application/json","CacheControl":"max-age=300","Body":"{\"id\":\"33333333-3333-3333-3333-333333333333\",\"name\":\"thing three\",\"asOf\":1524019758148}"}
2018-04-17 22:49:20 ... {"ETag":"\"edfee997659a520994ed18b82255be2a\""}
END ...
REPORT ... Duration: 167.66 ms    Billed Duration: 200 ms ... Max Memory Used: 36 MB    

12. Invoke the following command, after updating the bucket-suffix, to get the data from S3:

$ curl https://s3.amazonaws.com/cncb-materialized-view-s3-$MY_STAGE-bucket-<bucket-suffix>/things/33333333-3333-3333-3333-333333333333 | json_pp
{
 "asOf" : 1524019758148,
 "name" : "thing three",
 "id" : "33333333-3333-3333-3333-333333333333"
}

13. Use the console to delete the objects from the bucket before removing the stack.
14. Remove the stack once you have finished with npm run rm:lcl -- -s $MY_STAGE.