FaaS you like it (if Shakespeare had written Functions-as-a-Service)
- 1. FaaS You Like It (If Shakespeare had written Functions as a Service)
- 2. “All the world’s a stage, And all the men and women merely players; They have their exits and their entrances, And one man in his time plays many parts…”
- 3. Cast Cloud Architect - Ewan Slater
- 4. Agenda 1. What is FaaS (or “Serverless”) 2. The Fn Project 3. FDKs 4. As you like it - performed by Fn functions, written in Ruby & Java
- 5. Synopsis “As You Like It subverts the traditional rules of romance. Gender roles, nature and politics are confused in a play that reflects on how bewildering yet utterly pleasurable life can be.” - Royal Shakespeare Company
- 6. Bewilderment: Why dost thy Serverless Architecture have so many servers?
- 9. There are only two hard things in Computer Science: cache invalidation and naming things. - Phil Karlton
- 10. I don’t like “Serverless” as a name ● Hidden Servers ● Transient Servers ● Abstracted Infrastructure ● Anything really
- 11. "For everyone's sake, someone please come up with a better name than serverless” - Simon Wardley
- 14. “The Play’s the thing…”
- 15. Actor learns own part ● Cues (input) ● Lines (output) ● Stage Directions (state)
- 16. Actor ⇒ Function
- 18. Audience care about action
- 19. Not what happens backstage
- 20. Business doesn’t care about infrastructure
- 21. FaaS: action not infrastructure
- 22. Increase developer Productivity by adding another layer of Abstraction
- 24. FaaS ● Write small functions ● Do one thing well ● Easy to Understand ● Easy to Maintain ● Run on Abstracted Infrastructure (“Serverless”) platform
- 25. Avoid
- 26. What is “Serverless”? ● Serverless is an abstraction of infrastructure and its operations including provisioning, scaling, patching, etc. ● Serverless architecture is when an app is built entirely on serverless components (compute, storage, networking) ● Function as a Service (FaaS) is the compute component in a serverless architecture
- 27. For a fuller discussion... Mike Roberts article on MartinFowler.com https://martinfowler.com/articles/serverless.html “Fundamentally, FaaS is about running backend code without managing your own server systems or your own long-lived server applications.”
- 28. From Microservices to Functions
- 29. Granularity
- 30. Scale
- 31. Time
- 32. PaaS vs FaaS ● Granularity, Scale & Time ○ Paas (or IaaS) ⇒ (Micro)Service, long - running ○ FaaS ⇒ Function, invoked on demand If your PaaS can efficiently start instances in 20ms that run for half a second, then call it serverless. - Adrian Cockcroft
- 33. Functions != Functional ● Functions can have side effects ● Functions don’t have to be idempotent
- 34. FaaS Upsides ● Make development easier ● Improve developer productivity ● Increased agility (Dev & Business) ● Reduce costs (Dev & Operations)
- 35. FaaS Downsides ● “ball of mud” ● Lock - in ● Restricted choice ○ Language ○ Run - time environment
- 36. Language Support ● AWS ○ Node, Python, Java, C#, Go ● Google ○ Node ● Azure ○ C#, JavaScript, F#, (Java - preview)
- 38. (Or Erlang, or Rust, or FORTRAN etc.)
- 39. Choice: Write your functions in any language. Run them in any environment.
- 40. Fn Project: Write your functions in any language*. Run them in any environment*. *Supports / supported by Docker
- 41. Fn Project ( fnproject.io ) ● Open-source serverless compute platform ● Can be deployed to any cloud or on-premises ● Containers are primitives ● Active w/ 2500+ commits across 50+ contributors ● Independently governed with representation at CNCF ● support for the upcoming CloudEvents specification ○ (CNCF Serverless working group ) ● integration with the Serverless Framework toolkit
- 42. Functions as Containers ● Function and dependencies ● Single - purpose ● Self - Contained ● Stateless ● Ephemeral ● Run on Demand
- 43. An Fn Function ● Small chunk of code wrapped into container ● Input from STDIN & Environment ● Output to STDOUT ● Logs to STDERR
- 52. Fn deploy details ● Bump version in func.yaml ● Build container (multi stage) ● Push container to registry ● Create / Update function route MyFunc:0.0.2 MyFunc:0.0.2 MyFunc:0.0.2 Your code Fn Service myfunc → /r/myapp/myfunc:0.0.2 1 2 3
- 54. Fn Server ● “API Gateway” ● Manages apps and functions ○ (app ⇒ group of functions) ● Synchronous function calls ○ Executed immediately ● Asynchronous function calls ○ Queued and executed when capacity available ● Runs as a Container ● Hosts function containers using Docker - in - Docker
- 55. Docker in Docker ● Limited “blast radius” ○ Doesn’t affect outer VM ○ Kill Fn container & restart ● Docker version independence ○ (inner can differ from outer) ● Reduce chance of container name collisions
- 56. Architecture
- 57. Hot and Cold ● Cold Functions ○ Run once only ○ Terminate immediately ○ New container every invocation ● Hot Functions ○ Run at least once ○ Wait before terminating ○ Potentially reusable
- 60. Function Development Kits (FDKs) ● Developer writes a handler function to the FDKs interface ● FDK ○ Parses STDIN ○ Provides input data to function ○ Handles writing output and errors ○ Manages multiple invocations ● Makes it a lot easier to write hot functions
- 61. FDKs ● Ruby ( https://github.com/fnproject/fdk-ruby ) ● Others ○ Python ○ Go ○ Java ○ Node ○ Rust ○ ...more on the way...
- 62. Without an FDK ● Dockerfile ● func.yaml ● func.* (e.g. func.sh) ● DIY
- 64. Orchestration
- 65. Flow ● Promises based Orchestration ○ No new “special” language ○ Composable ○ Flexible ○ Supports “Saga Pattern” ● A Flow is... ○ ...written in Code ○ ...written as Function ○ ...deployed as a function (within an application)
- 66. Flow ● Language Support: ○ Java ○ Python ○ Node ● In the works: ○ Go ● To - do: ○ Ruby
- 67. As You Like It bitbucket.org/ewan_slater/comedy/src/master/
- 68. Summary ● FaaS ⇒ Greater developer productivity ● Fn Project ⇒ FaaS Framework ○ Open Source ○ Portable ○ Language Agnostic ○ Multiple FDKs ● Feedback and contributions welcome!
- 69. Links & Contact ● Fn Project ( fnproject.io ) ○ github.com/fnproject ○ Slack ● Twitter ○ Fn Project: @fnproj ○ Me: @ewanslater
- 70. Proceed, proceed: we will begin these rites, As we do trust they'll end, in true delights. (all exit to the pub)