Introduction to Elixir and Phoenix

Introduction and overview to Elixir and Phoenix

Transcript

1. INTRODUCTION TO ELIXIR & PHOENIX KARMEN BLAKE
2. ME ▸Crafting code since 2000 ▸Blessed to work for silicon valley startups, consultancies, agencies, corporations ▸Instructor at Spokane Community College, 2000-2007, teaching computer science and web development
3. ELIXIR (OR ANY TECH): NOT A SILVER BULLET
4. MY STORY
5. RE: CODING JOURNEY ▸College (late 90s): BASIC, Pascal, C++ ▸Early days (2000-2005) - Java and PHP ▸Then… Lots of Ruby (2005 - present) ▸Taught at SCC (converted curricula from Java) ▸Blog posts, presentations, interviews ▸High paying jobs ▸Still a joy to develop in
6. ERLANG: WHERE ELIXIR CAME FROM
7. ERLANG ▸I read “Programming Erlang: Software for a Concurrent World” by the late Joe Armstrong, 2007 ▸Created in 1986 at Ericsson ▸“…used to build massively scalable soft real-time systems with requirements on high availability.” ▸“…telecoms, banking, e-commerce, computer telephony and instant messaging”
8. ERLANG ▸1998 Ericsson announced the AXD301 switch, containing for a million lines of Erlang and reported to achieve a high availability of nine “9”s. ▸Cisco reports that 90% of all internet traffic goes through Erlang controlled nodes ▸Scalable, fault-tolerant, functional (immutable data, functions, pattern matching, tail recursive, etc.)
10. ERLANG AT APPLE (2011-2012) ▸Wrote API web services in Erlang ▸Used Riak database (written in Erlang) cluster as an internal asset CDN ▸Used CouchDB to deliver real-time web applications
11. ELIXIR
12. ELIXIR??????
13. ELIXIR ▸Created by Jose Valim in 2011 ▸“…dynamic, functional language designed for building scalable and maintainable applications.” ▸“…leverages the Erlang VM (BEAM), known for running low-latency, distributed and fault-tolerant systems, while also being successfully used in web development and embedded software domain.
14. ELIXIR ▸What Erlang provides: scalable, fault- tolerant, functional ▸Ruby-like syntax (not semantics) ▸Extensible/DSLs ▸Tooling/ecosystem ▸package management, testing, iex (repl)
15. Functional Programming
18. PHOENIX FRAMEWORK
19. PHOENIX FRAMEWORK
20. THINGS YOU’LL RECOGNIZE ▸Resourceful Routing ▸Controllers (request/response, JSON apis) ▸Views (presenters, helpers) ▸Templates - markup, db-backed forms, error display, partials, etc. ▸Tasks (ie. Rake, called Mix in Phoenix) - running generators, etc. ▸Console (REPL for code and database tinkering) ▸Database layer (Ecto) ▸Testing ▸Easy Heroku deployments
21. QUICK NOTE ON TEMPLATES… THEY ARE FAST! ▸Phoenix templates are compiled into functions ▸Use linked-lists to build templates vs string concatenation (as most other web frameworks do) ▸Consumes much less memory
22. OOOOHHHH AAAAAHHHHH ▸Presence - register information on a topic and replicate it transparently across a cluster. Common use-case is users currently online (uses conflict- free replicated data type CRDT) ▸Contexts - standard way to define domains that cleanly separate concepts from technical implementation. ie. Accounts (users, authentication, etc.) ▸Channels - soft real-time communication between millions of connected clients (ie. chat room, breaking news, vehicle map tracking, multiplayer games, etc.). Think ActionCable but can actually scale ;p ▸Umbrella - put code in organized apps that enforce domain code to stay away from web interactions - ie. web, db, domains “Phoenix is not your app” ▸Pub/Sub - Pubnub, services
23. PHOENIX LEVERAGING ELIXIR/ERLANG (OTP) ▸ETS/Genservers - Think Redis. Available right in the VM ▸Tasks - Asynchronous background work (Sidekiq). Available right in the VM ▸Supervisors - Architect a self-healing system that can recover when unexpected things happen. “Let it crash!”. Available right in the VM. Think Akka.
25. WHAT IS LIVEVIEW? ‣ Phoenix LiveView is an exciting new way to build interactive, real-time web applications in Elixir, writing little or no custom JavaScript. ‣ LiveView, built on Phoenix’s excellent websocket report, harnesses the Erlang VM’s ability to run millions of tiny, isolated, stateful processes. ‣ LiveView simplifies development by keeping the view logic server-side, yet achieves stunningly fast updates and low latency.
26. SPIKES ▸Work: ▸Real-time Phoenix dashboard displaying Trello board info, bug counts, Zoom conference room info, Github PRs ▸LiveView app for Zoom conference room and participant information
27. PHOENIX LIVEVIEW DEMOS https://phoenixphrenzy.com/results
28. FINISHED. THANK YOU!
29. CITATIONS ▸ https://en.wikipedia.org/wiki/Erlang_(programming_language) ▸ https://www.erlang.org ▸ https://elixir-lang.org ▸ https://www.meetup.com/rubymeetup/events/14908915/ ▸ https://pragprog.com/book/phoenix14/programming-phoenix-1-4 ▸ https://twitter.com/chris_mccord/status/659430661942550528 ▸ https://dockyard.com/blog/2018/12/12/phoenix-liveview- interactive-real-time-apps-no-need-to-write-javascript