Let's create stateful systems, by Elixir

Transcript

1. Let's create stateful systems, by Elixir
2. . ｡oO( さっちゃんですよヾ( 〃l _ l) ﾉﾞ☆)
3. I'll show you a number.
4. 2
5. Two
6. Ⅱ
7. ⼆
8. 2 is a number of collison & collaboration.
9. I & you hot & ice stand up & lie down inside & outside
10. stateless & stateful
11. Function is stateless. f : x -> y e.g. Web server
12. Dialogue is stateful. Alice : X. Bob : Y. Alice : X. Bob : Z. Most of the system is stateful.
13. Elixir
14. Elixir is a functional programming language. Functional programming is stateless. All data of Elixir is immutable. [x, 3, x] = Enum.map([1,2,1], &(&1 + 1)) assert 2 == x // Many lines that don't reassign to `x`. assert 2 == x
15. Elixir has processes. 29 = Task.async(fn -> 29 end) |> Task.await
16. Process has state. agent = Agent.start_link(fn -> 29 end) 29 = Agent.get(agent, &(&1)) Agent.update(agent, &(&1 + 13)) 42 = Agent.get(agent, &(&1))
17. State should be updated in a transaction. State shold interact & isolate each other. Accessing to state should be scaled in-out. Server with state should be updated gracefully. Elixir has all of these!
18. State should be updated in a transaction. (No shared state) State shold interact & isolate each other. (Application, Supervisor) Accessing to state should be scaled in-out. (GenStage, Task, Register, Erlang cluster) Server with state should be updated gracefully. (Hot code swap)
19. We can create stateful system easy, by constructing stateless parts.
20. How we can start Elixir? Let's create some applications. * Web application with Phoenix. * Slack bot.
21. Phoenix is a Web application framework that familiar with WebSocket. https://hexdocs.pm/phoenix/overview.html
22. React is available (✿ >ヮ ╹ )-♡ Let's create a realtime interaction ∩ (＞ ◡ ＜*)∩ ♡ https://speakerdeck.com/ne_sachirou/phoenix-livereact
23. Create a Slack bot. https://github.com/BlakeWilliams/Elixir-Slack (Easy, so no topic.)
24. Installing Elixir. asdf https://asdf-vm.com/ asdf plugin-add erlang asdf install erlang 22.0.7 asdf plugin-add elixir asdf install elixir 1.9.1
25. Text editor? VSCode with mjmcloug.vscode-elixir works.
26. Format & lint. InnerCotton https://github.com/ne-sachirou/inner_cotton is a set of standard development tools. mix cotton.init mix cotton.lint --fix
27. Docker image (You need Docker :-) Fix major ver.s both Erlang & Elixir. docker run -it --rm nesachirou/elixir:1.9_erl22
28. Textbook & document. Official guide : https://elixir-lang.org/ Official document : https://hexdocs.pm/elixir/Kernel.html Online textbook : https://elixirschool.com/ja/ Textbook : https://tatsu-zine.com/books/programming-elixir-ja
29. https://speakerdeck.com/ne_sachirou/elixirwan-quan-nili-jie-sita
30. Advanced resources
31. Erlang in Anger https://ymotongpoo.github.io/erlang-in-anger/text-ja.pdf You want to read this… before production.
32. https://speakerdeck.com/ne_sachirou/sutetohurudeda-gui-mo- akusesufalsearusoft-realtimenagemusabawoeasynitukuru
33. https://speakerdeck.com/ne_sachirou/elixir-on-containers
34. https://speakerdeck.com/ne_sachirou/phoenix-at-scale
35. https://speakerdeck.com/ne_sachirou/ddd-data-driven-development