Scalaの(俺的)イケてる ライブラリ紹介LT

2017/03/21に「Scala x AdTech Studio」というイベントのLTで発表した内容です。

Transcript

1. Scala x AdTech Studio Scalaͷ(Զత)ΠέͯΔ
 ϥΠϒϥϦ঺հLT
2. ஫ҙ - ScalaͰͷ։ൃܦݧ͋Δਓ޲͖ͷ಺༰ - Akkaͷ࿩͸͠·ͤΜ
3. ϥΠϒϥϦ঺հ
4. Refined - ܕʹಠࣗͷ੍໿ΛՃ͑ΒΕΔϥΠϒϥϦ - Haskellͷಉ໊ɾಉػೳͷϥΠϒϥϦ
 ʹΠϯεύΠΞ͞ΕͨΒ͍͠
5. Refined type UserId = Int Refined Positive val userId: UserId = 0 // compile error type Probability = Double Refined Closed[W.`0.0`.T, W.`1.0`.T] val p: Probability = 1.2 // compile error
6. PureConfig - ઃఆϑΝΠϧಡΈࠐΈ༻ϥΠϒϥϦ - TypesafeConfigͷϥούʔ - case classΠϯελϯεʹϚοϓͯ͘͠ΕΔ - HOCON, JSONʹରԠ - Refinedʹ΋ରԠ
7. PureConfig // development.conf (HOCONܗࣜ)
 include “application.conf” redis { host: “127.0.0.1” port: 6379 } // Config.scala case class Config(redis: RedisConfig) case class RedisConfig(host: String, port: Int) val confPath = ConfigFactory.load(“development.conf”) val config = loadConfig[Config](confPath).get assert(config.redis.host == “127.0.0.1”) assert(config.redis.port == 6379)
8. circe - JSONΛScalaͷΫϥεʹϚοϐϯά͢Δ
 - json4sΈ͍ͨͳ - ʮαʔγʔʯͱಡΉ - core෦෼͸reflectionͳ͠Ͱ࣮૷ - ύϑΥʔϚϯεΛͪΌΜͱܭଌɾߟྀ࣮ͨ͠૷ - RefinedʹରԠ
9. json4s΍ΊΑ͏ ͱ༗໊ͳ͋ͷํ΋ݴ͓ͬͯΓ·͢ - Twitter্Ͱʮ@xuwei_k json4sʯͰݕࡧ
10. Finch - finagle্Ͱಈ͘HTTP APIΛ࡞ΔͨΊͷ
 ϧʔςΟϯάϥΠϒϥϦ - circeͳͲͱͷ࿈ܞ͕ྑ͍ - ଎͍
11. Finch case class User(name: String, age: Int) val getUser: Endpoint[User] = get(“user” :: int) { userId: Int => val user: User = User.getById(userId) user } val createUser: Endpoint[Boolean] = post(“user” :: jsonBody[User]) { user: User => // create user true } Http.server.serve(“:80”, (getUser :+: createUser).toService)
12. doobie - RDBMS΁ͷΫΤϦ݁ՌΛऔಘ - ScalaͷΫϥεʹϚοϐϯά΋Մ - ORMͰ͸ͳ͍
 - SQL͸ࣗ෼Ͱॻ͔ͳ͍ͱ͍͚ͳ͍ - ΋͏͙͢RefinedʹରԠ
13. doobie sql”SELECT * FROM users WHERE age = $age” .query[String] .process .take(5) .list .transact(xa) .unsafePerformIO .foreach(println)
14. doobie sql”SELECT * FROM users WHERE age = $age” .query[String] .process .take(5) .list .transact(xa) .unsafePerformIO .foreach(println) ͜ͷ෦෼͸Prepared StatementΛ
 ࢖ͬͯจࣈྻૠೖ͞ΕΔͷͰɺ
 SQLΠϯδΣΫγϣϯʹ΋ڧ͍

15. Cats - ؔ਺ϓϩάϥϛϯά༻ϥΠϒϥϦ - ScalazͷޙൃϥΠϒϥϦ - ༗໊ϥΠϒϥϦ͸ Scalaz -> Cats
 ʹ৐Γ׵͑ͭͭ͋Δ(ؾ͕͢Δ)
16. ࣾ಺Ͱ͸͜Μͳ
 ϓϧϦΫΤετ΋…
17. ͦͷଞ
18. Typelevel.scala
 (ίϛϡχςΟ) - Refined, circe, Finch
 doobie, Cats
 ͳͲͷϥΠϒϥϦ͕ࢀՃ - ͜͜ʹ͋ΔϥΠϒϥϦ͸
 Ұ௨Γ͓͓͖͍͑ͯͨ͞