scala-graal

libraryDependencies ++= Seq(
  "com.github.japgolly.scala-graal"  %% "core"           % "1.2.0"
  "com.github.japgolly.scala-graal" %%% "core-js"        % "1.2.0"
  "com.github.japgolly.scala-graal" %%% "ext-boopickle"  % "1.2.0"
  "com.github.japgolly.scala-graal"  %% "ext-prometheus" % "1.2.0"
)

Goals

• Make it quick, easy and safe to interface with embedded languages from Scala
• Hide and automate a lot of required GraalVM boilerplate
• Support React SSR for Scala.JS applications

Demo

import japgolly.scalagraal._

// Use semantics and implicit config for JS
// (GraalVM also supports Python, R, Ruby, LLVM)
import japgolly.scalagraal.js._
import GraalJs._
// 1. Pre-compile expression functions for fast invocation.
// 2. Typeclasses translate and/or marshall data between JVM and JS.
val expr: (Int, Int) => Expr[String] =
  Expr.apply2((a, b) => s"($a + $b) * 2 + '!'").compile(_.asString)
// Use a basic synchronous JS environment
val ctx = GraalContext()
val result = ctx.eval(expr(3, 8))
assert(result == Right("22!"))

Learning

• API & how to use
• Recipes
• Scala SSR tutorial (part 1)
• Scala SSR tutorial (part 2)

Features

• Expressions
  • composition
  • purity
  • result parsing
  • error handling
  • null handling
  • binding typeclasses
  • binding codecs (eg binary/json/whatever)
• Service
  • single-threaded
  • multi-threaded pool
  • synchronous
  • asynchronous
  • optional time limits
  • before/around/after hooks
  • automatic metrics
• Warmup
  • ability to warmup VM
  • rules (eg.

    up to 10000 reps/thread & up to 30 sec | until completes within 20ms

    )
• React SSR (Server-Side Rendering)
  • support for rendering JS components from JVM
  • conversion to constant-time (conditionally)

  • window

    and especially

    window.location

    management
• Integrations
  • Prometheus - export metrics to Prometheus
  • BooPickle - marshall data back and forth using binary codecs