AWS Lambda and Serverless framework: lessons learned while building a serverless company

Planet9energy.com is a new electricity company that is building a sophisticated analytics and energy trading platform for the UK market. Since the earliest days of the company we took the unconventional decision to go serverless and finally we are building the product on top of AWS Lambda and the Serverless framework using Node.js. In this talk we will discuss why we took this radical decision, what are the pros and cons of this approach and what are the main issues we faced as a tech team in our design and development experience. We will discuss how normal things like testing and deployment need to be re-thought to work on a serverless fashion but also the benefits of (almost) infinite auto-scalability and the piece of mind of not having to manage hundreds of servers. Finally we will underline how Node.js seems to fit naturally in this scenario and how it makes developing serverless applications extremely convenient.

Thanks to Padraig O'Brien and Luciano Mammino for speaking this month.

Speakers Bio:

Padraig O'Brien

Podge @Podgeypoos79 is a software engineer for over 15 years, most of that was spent developing in .NET and SQL Server, designing and building large scale data intensive applications. Lately he has shifted towards open source technologies and is spending most of his time learning Node.js, Scala and cool data tech like Spark, Cassandra. He is also working on a “super-secret” project called UnicornDB, don’t tell anybody!

In his spare time he helps out with organising some meetups like NodeSchool Dublin, NodeSchool Dun Laoghaire and teaching Kanban via Agile Lean Ireland.

Luciano Mammino

Luciano @loige is a Software Engineer born in 1987, the same year that the Nintendo released “Super Mario Bros” in Europe, which, “by chance” is his favourite game! His primary passion is code and he is extremely fascinated by the web, smart apps and everything that's creative like music, art and design. He started coding at the age of 12 using his father's old i386 provided only with DOS and the qBasic interpreter.He is a senior software developer at Planet9Energy in Dublin and he loves JavaScript (React/Node.js). He is also the co-author of "Node.js design patterns" 2nd edition (Packt, http://amzn.to/1ZF279B).

Hosted by Intercom, sponsored by Nearform and organised by Node.js Dublin (https://www.meetup.com/Dublin-Node-js-Meetup/events/236870576/)

Transcript

1. AWS Lambda & Serverless framework Lessons learned while building a serverless company 26/01/2017 @Podgeypoos79 - @loige
2. Luciano Mammino • @loige on Twitter • Lmammino on GitHub • Blog at loige.co • Co-author of: Node.js Design Patterns (Second Edition)
3. Padraig O’Brien (a.k.a “Podge”) • @podgeypoos79 on Twitter • Does not have a book (yet…) • Organiser of Nodeschool Dublin and Dun Laoghaire • Organiser of Dublin Serverless meetup • He is writing his own database, unicorndb
4. Agenda • Planet 9 Energy • Serverless • Security • Quality • Developer Experience • Costs • Lessons learned
5. planet9energy.com
7. 17.520 * * 24 Meter readings Customer size Data versions ≈4 billion data pts / year (tot.) SMALL customer ≈3 mln data pts / year MEDIUM customer ≈20 mln data pts / year BIG customer ≈110 mln data pts / year ( Per customer / year )
8. • Limited number of “Full stack” engineers • Write & deploy quality code as fast as possible • Adopt hot and relevant technologies • No servers... or more to the point, NO CALLS AT 2 AM! Our requirements
9. Early experiments
10. Current Technology
11. “Serverless” Meaning Serverless framework AWS Lambda
12. What does “serverless” mean?
13. Why Serverless framework?
14. Anatomy of Serverless.yml Serverless.yml header
15. Defining functions and events
16. Why?
17. What is a lambda? • Function as a service (FAAS) • Pay for invocation / processing time • Virtually “infinite” auto-scaling • Focus on business logic, not on servers daaaa!
18. Lambda as micro-services • Events are first-class citizens • Every lambda scales independently • Agility (develop features quick and in an isolated fashion) Classic micro-services concerns: • Granularity (how to separate features? BDD? Bounded Contexts?) • Orchestration (dependencies between lambdas, service discovery…)
19. Anatomy of a Lambda in Node.js
20. Some use cases • REST over HTTP (API Gateway) • SNS messages • Schedule/Cron • DynamoDB data changes • S3 files changes • IoT
21. HTTP REQUEST - API Call POST /hello/Elvis?foo=bar { “test”: “body” }
22. Security Authentication Authorization Sensitive data
23. Authentication (JWT tokens) Custom “authorizer lambda” “Who is the current user?”
24. Users API 1 Authentication Authorizer API 2 API 3 Credentials API Request JWT token JWT token Verify credentials Validate token & extract userId User: Podge Pass: Unicorns
25. Authorization “Can Podge trade for Account23 ?” User Action Resource
26. Authorization • Custom ACL library imported by every lambda • Built on top of: ◦ node-acl ◦ Knex.js • Persistence in Postgres User Action Resource Podge trade Account23 Podge changeSettings Account23 Luciano delete * ... ... ...
27. ACL Lib Example
28. Environment variables
30. Quality Testing Continuous Integration Deployment
31. Testing JEST Node-TAP
32. Unit Testing • Split business logic into small testable modules • Use dependency injection for external resources (DB, Filesystem, etc.) • Mock dependencies with Sinon • Aim for 100% coverage
33. • Use child_process.exec to launch “serverless invoke local” • Use node-tap to make assertions on the output • Test environment recreated locally with docker (e.g. Postgres test DB). • Cannot always test locally (Redshift, SNS, SQS…) Functional Testing
34. Functional test with sls invoke local
35. Building the project
36. Babel custom preset (transpile to Node 4.3.2)
37. Build process JSdoc Up to 90% code size reduction Using Webpack 2 “tree-shaking”
38. Continuous Integration Git-Flow • Check code style (ESLint) • Run unit tests • Build the project • Run functional tests • If commit is on “master”: Create deployable artifact • Develop features/fixes locally using git branches • Push to GitHub
39. Deployments local test dev qa production Deploy lambdas and React apps
42. Downloading the artifact from CircleCI
43. Deploying the code using Serverless
44. Developer Experience Local development Debugging Monitoring
45. • Develop locally - Invoke local. • Deploy to AWS. • Invoke on AWS and stream the logs. • This is a SLOW feedback loop. • Lots of requests to improve local dev. • Plugins are helping to improve this. Local development
46. Serverless Plugins
47. Serverless Offline
48. Serverless Api Gateway Logs
49. Serverless Mocha
50. Monitoring
62. Cost The formula Cost forecasts
63. $ = Time * Memory * Invocation
64. http://serverlesscalc.com
65. Our current Lambda costs
66. Lessons learned ( we found out…)
67. DEBUGGING
68. How do we do debug then... • console.log … • Using debug module • Enabling detailed logs only when needed (per feature)
70. Learn Cloudformation
73. Api Gateway Custom domain mapping It is a manual step…
74. With Api Gateway... You have 10 30 seconds!
75. AWS Lambda limitations • 512 MB of TMP space • Lambdas can only execute for 300 seconds • Request Response size of 6 MB • Event size of 128 Kb • Max 50 MB for deployment package
76. AWS Soft limits http://docs.aws.amazon.com/general/latest/gr/aws_service_limits.html
77. Cold starts... ☃
78. https://www.iopipe.com/2016/09/understanding-aws-lambda-coldstarts/
79. serverlessbeer.com is a real thing! Well… it’s not, but it’s a good idea! (read the tutorial)
80. Recap • Serverless architectures are COOL! ◦ Infinite scalability at low cost ◦ Managed service ◦ Still has some limitations • Managing a project might be hard but: ◦ Technology progress and open source projects (Serverless.com) will make things easier
81. Planet 9 Energy tech-team We are hiring :) Peter Saŝa Podge Luciano YOU? Alberto Joe Domagoj Hugh Gus Ruth Check out Loki.js
82. THANK YOU Planet9energy.com - tech@planet9energy.com Special Thanks to @johnbrett_ Use the , Luke!