ZIO learning - graphql API / published by https://github.com/dacr/code-examples-manager #1359058d-f8c3-4a04-bdea-5b520c5de8f8/a1f8779770b33cf81357cc3bfa45dfd583a1b18c

zio-learning-graphql-caliban-1.sc

// summary : ZIO learning - graphql API
// keywords : scala, zio, learning, pure-functional
// publish : gist
// authors : David Crosson
// license : Apache License Version 2.0 (https://www.apache.org/licenses/LICENSE-2.0.txt)
// id : 1359058d-f8c3-4a04-bdea-5b520c5de8f8
// created-on : 2021-04-03T15:31:41Z
// managed-by : https://github.com/dacr/code-examples-manager
// execution : scala ammonite script (http://ammonite.io/) - run as follow 'amm scriptname.sc'

// Functional GraphQL library for Scala : https://ghostdogpr.github.io/caliban/
// inspired from https://ghostdogpr.github.io/caliban/docs/#a-simple-example

// ---------------------
//> using scala "3.4.2"
//> using dep "com.github.ghostdogpr::caliban:2.0.0"
// ---------------------

import zio.*
import caliban.GraphQL.graphQL
import caliban.RootResolver

// =========================================================================================

object Embedded extends ZIOAppDefault {
  // =========================================================================================
  object ASimpleExample {
    case class Character(firstName: String, lastName: String, age: Int, gender: String)

    val characters = List(
      Character("sarah", "connor", 34, "f"),
      Character("john", "connor", 12, "m"),
      Character("kyle", "reese", 24, "m"),
      Character("ginger", "ventura", 33, "f"),
      Character("miles", "dyson", 42, "m")
    )

    def getCharacters: List[Character]                = characters
    def getCharacter(name: String): Option[Character] = characters.find(_.firstName == name)
  }

  // =========================================================================================

  object Schema {
    import ASimpleExample.{Character, getCharacter, getCharacters}
    // schema
    case class CharacterName(name: String)
    case class Queries(
      characters: List[Character],
      character: CharacterName => Option[Character]
    )
    // resolver
    val queries = Queries(getCharacters, args => getCharacter(args.name))
  }

  import Schema.queries

  val api = graphQL(RootResolver(queries))

  // -----------------------------------------------------------
  val query = """ { characters { firstName lastName } }"""
  //val query = """ { character(name: "john") { firstName age } }"""

  override def run =
    for {
      _           <- Console.printLine("Testing caliban...")
      interpreter <- api.interpreter
      _           <- Console.printLine("Executing query...")
      result      <- interpreter.execute(query)
      _           <- Console.printLine(result.data.toString)
    } yield ()

}

Embedded.main(Array.empty)