Building the Ruby × Elixir Conf App

Reject Conf 2018

Transcript

1. Building the Ruby × Elixir Conf App
2. 皰玡㳓 @zetavg ‣ Բ狝夺䌌Ꭺ಑褾 Developer ‣ Ruby, JavaScript, Elixir, ReasonML, C ‣ ࡅ稭碝ᄤ獖槹ጱದ蔩 蚤桽螂犋݄ ‣ 磧蜱ࣁሻӞ犚 Functional 承᥺ ‣ 瓵మฎአ硳ሲ牏ߝ搡膏硳胼ٍّጱොୗ樄咳敟誢
3. Conference apps ‣ Schedule, personal schedule, map, events, announcements ‣ Facebook F8 ‣ Google I/O ‣ Apple WWDC ‣ Web Summit ‣ Build-in chat for attendees
4. Let's build one for Ruby × Elixir Conf!
5. What to use? ‣ App: ReasonML ‣ Backend: Elixir ‣ API: GraphQL ...why so many new things?
6. A helpful programming language can teach you how to write robust programes
7. Some of them restricts you with human defined rules ̿纷ୗ݈翥捌犋螂ԧ牧অ簡̀
8. Others teaches you some CS ways to think: data structures, theory of computation, type theory, formal methods ̿߶牧ܻ㬵౯䛑扗蝡䰬௏ᘍ㺔氂牏蝡愊మဩ磪綠笙牧憽஑݈蝱ྍԧ̀
9. Elixir Functional, Concurrent, Fault-tolerance, Extendable via macros, Based on Erlang
10. Functional “I don’t want to hide data. I want to transform it.” (Quoted from “Programming Elixir” by Dave Thomas)
11. Concurrent “Most programmers treat threads and processes as a necessary evil; Elixir developers feel they are an important simplification.” (Quoted from “Programming Elixir” by Dave Thomas)
12. Concurrent https://hashrocket.com/blog/posts/websocket-shootout
13. Concurrent https://hashrocket.com/blog/posts/websocket-shootout
14. Expectable Conventions length [1, 2, 3] # "length" tuple_size {:ok, "hello"} # "size" ̴ https://elixir-lang.org/getting-started/basic-types.html#lists-or-tuples
15. More about Elixir (౯ᛔ૩ጱ殼ଧ) 1. elixirschool.com物獈槹ݻጱ承ဩ硽䋊 2. elixir-lang.org物ਥො guides 䌃஑盄অ 3. 獢碍ୗ翥纷: ℂ Elixir & Phoenix 獈槹牐 羬ڜ物य़വ牧Ӿ෈牧অ捝ฃ睞 4. Programming Elixir物౯ፓ獮ݝ磪፡蝡Ӟ๜ (ׯ) ୌ捍䷱䌃螂 Functional ጱ๏݋獨ݝ捝 1 ~ 2牧ݢ犥捝ک 3 ౲ 4ҁ౲ℂ 3牏4 樄ত 捝҂ٚ㵕ಋ牧犋簁䨝ᤩ২֦̿蝡䰬䌃疰 OO 眖ࠡ牐̀ҁ藮
16. ݢ犥肯䔶ᘏ౯ݶԪࣁ Ruby × Elixir Conf 拻 Elixir ጱ捍纷 ᒫӞॠӥ܌ࣁ 1001
17. ReasonML Write type safe, functional, fast code with the help form OCaml. Compiles to JavaScript.
18. ReasonML ‣ Reason (syntax): JavaScript-developer-friendly syntax of OCaml ‣ BuckleScript: OCaml to JavaScript compiler
19. Benefits form OCaml ‣ Battle-tested language created in 1996 ‣ Functional and immutable by default ‣ Solid type system: structural, inferred and sound ‣ Flow is written in OCaml! ‣ Ecosystem & tooling ‣ ocaml-language-server
20. Why ReasonML ‣ Type safety ‣ Fast compile time ‣ Generates fast code ‣ The language of React ‣ When Reason's creator created React, the prototype was written in Standard ML1 ‣ ReasonReact: All your ReactJS knowledge, codified ‣ Fun 1 OCaml is also a member of the ML programming language family.
21. Pattern Matching
22. Pattern Matching - Switch
23. Pattern Matching - Switch in function ‣ ଉ憎አဩ
24. Pattern Matching - Function ‣ 䌘㻌㮆 argument ፗ矑狶 pattern matching 犖ݢ犥አ fun ጱ䌃ဩ
25. Varient Type ‣ ݢ犥ቘ薹౮胼癲独ጱ enum ‣ አ type 㬵狶 pattern matching ‣ 犖胼አ㬵玟獤㻌֖2 e.g.: Pt(2.)牏Px(12.) 2 Mars Climate Orbiter, costed hundreds of millions of US dollars, crashed because of a pound-force-seconds and newton-seconds type mismatch in 1999.
26. "Option" for nullable ‣ 疰ฎ Haskell 愊ጱ Maybe a = Just a | Nothing
27. Type System ‣ Prevent mistakes such as typo, null, wrong argument... ‣ Prevent unexpected behavior changes when adding new features ‣ Document!
28. Type system: Structural v.s. Nominal (* These functions takes a list of <something> and returns a <something>. *) let first: 'a list -> 'a = fun (item::_) -> item let second: 'a list -> 'a = fun (_::item::_) -> item (* * The type of function that takes a list of string and returns a string. * Note that this type signature is different from the two functions above. *) type listOfStringSelector = string list -> string (* A function that applies a listOfStringSelector to a list of string. *) let selectListOfStringBy: listOfStringSelector -> string list -> string = fun f -> fun l -> f l
29. Type system: Structural v.s. Nominal let second: 'a list -> 'a = fun (_::item::_) -> item type listOfStringSelector = string list -> string let selectListOfStringBy: listOfStringSelector -> string list -> string = fun f -> fun l -> f l (* * The structure of * "function that takes a list of <something> and returns a <something>" * is comaticatible with * "function that takes a list of string and returns a string ", * so the code compiles! *) let b = ["a"; "b"; "c"; "d"] |> selectListOfStringBy second
30. Type system: Inferred We can remove all the type annotations. OCaml will infer them correctly. (* * OCaml will know that the type of these functions are "'a list -> 'a", * as the argument is patteren-matched as a list and will return an * item from the list. *) let first = fun (item::_) -> item let second = fun (_::item::_) -> item
31. More about ReasonML ‣ 2ality Ӥጱ "What is ReasonML?" 羬ڜ෈ ‣ Reason ‣ ReasonReact ‣ BuckleScript
32. GraphQL Data query language
33. GraphQL ‣ Graph data query language ‣ Schema first development ‣ Easily parallels frontend & backend develop ‣ Easier communication for developers ‣ No need of extra document
34. Sketch out the schema using Apollo Launchpad
35. Using GraphQL with Reason
36. Demo
37. WIP https://github.com/XConf
38. Thanks & Q&A https://github.com/XConf