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-dynamodb --path cncb-materialized-view-dynamodb

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

service: cncb-materialized-view-dynamodb

provider:
  name: aws
  runtime: nodejs8.10
  iamRoleStatements:
    ...
  environment:
    TABLE_NAME:
      Ref: Table

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

resources:
  Resources:
    Table:
      Type: AWS::DynamoDB::Table
      Properties:
        TableName: ${opt:stage}-${self:service}-things
        AttributeDefinitions:
          ...
        KeySchema:
          - AttributeName: id
            KeyType: HASH
        ...

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 = {
    TableName: process.env.TABLE_NAME,
    Item: thing,
  };

  const db = new aws.DynamoDB.DocumentClient();
  return _(db.put(params).promise());
};

module.exports.query = (id, context, callback) => {
  const params = {
    TableName: process.env.TABLE_NAME,
    Key: {
      id: id,
    },
  };

  const db = new aws.DynamoDB.DocumentClient();
  db.get(params, callback);
};

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

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

9. Review the stack, functions, and table in 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 two","id":"22222222-2222-2222-2222-222222222222"}}}'
{
 "ShardId": "shardId-000000000000",
 "SequenceNumber": "49583553996455686705785668952916415462701426537440215042"
}

11. Take a look at the listener function logs:

$ sls logs -f listener -r us-east-1 -s $MY_STAGE
START ...
2018-04-17 00:54:48 ... event: {"Records":[...]}
2018-04-17 00:54:48 ... {"id":"39070dc13de0eb76548506a977d4134c","type":"thing-created","timestamp":1523939340000,"tags":{"region":"us-east-1"},"thing":{"new":{"name":"thing two","id":"22222222-2222-2222-2222-222222222222"}}}
2018-04-17 00:54:48 ... params: {"TableName":"john-cncb-materialized-view-dynamodb-things","Item":{"id":"22222222-2222-2222-2222-222222222222","name":"thing two","asOf":1523939340000}}
END ...
REPORT ... Duration: 306.17 ms    Billed Duration: 400 ms ... Max Memory Used: 36 MB    

12. Invoke the query command:

$ sls invoke -r us-east-1 -f query -s $MY_STAGE -d 22222222-2222-2222-2222-222222222222
{
    "Item": {
        "id": "22222222-2222-2222-2222-222222222222",
        "name": "thing two",
        "asOf": 1523939340000
    }
}

13. Remove the stack once you are finished with npm run rm:lcl -- -s $MY_STAGE.