@everymundo/aws-kinesis-client

aws-kinesis-client

A helper to ease the usage of Kinesis Data Streams in Lambda Functions while cutting costs

• Instalation
• Why we created this package
• Usage
  • Lambda Consumer
  • Data Producer

Instalation

npm install @everymundo/aws-kinesis-client

Usage

Lambda Consumer

EXAMPLE: Usual AWS Lambda handler for an AWS Kinesis event

// index.js
const handler = async (event) => {
  const myRecords = []
  for (const record of event.Records) {
    myRecords.push(record)
    // ... do your processing of the record
  }

  return myRecords
}

EXAMPLE: Of how simple is the code chage

// index.js
const kinesisParser = require('@everymundo/aws-kinesis-client/lib/parse-kinesis-record')

const handler = async (event) => {
  const myRecords = []
  for (const record of kinesisParser.flatJsonRecordsLambda(event.Records)) {
    myRecords.push(record)
    // ... do your processing of the record
  }

  return myRecords
}

You can test the implementation with a sample code as the following:

// index.js
const kinesisParser = require('@everymundo/aws-kinesis-client/lib/parse-kinesis-record')

const handler = (event) => {
  // flatJsonRecordsLambda expects that each element in event.Record to be
  // a valid lambda Kinesis Record input with
  // {"eventSource": "aws:kinesis","kinesis":{"data":"W3siYSI6MX0seyJhIjoyfSx7ImEiOjN9XQ=="}}
  const myRecords = []
  for (const record of kinesisParser.flatJsonRecordsLambda(event.Records)) {
    // record is a single object
    myRecords.push(record)
  }

  return myRecords
}

const assert = require('assert')
const testHandler = () => {
  const event = {
    Records: [
      { eventSource: 'aws:kinesis', kinesis:{ data: 'W3siYSI6MX0seyJhIjoyfSx7ImEiOjN9XQ==' } },
      { eventSource: 'aws:kinesis', kinesis:{ data: 'W3siYSI6NH0seyJhIjo1fSx7ImEiOjZ9XQ==' } }
    ]
  }

  const response = handler(event)

  assert(response.length === 6)
  assert(JSON.stringify(response) === '[{"a":1},{"a":2},{"a":3},{"a":4},{"a":5},{"a":6}]')
}

Data Producer

TODO