OpenAPI Schema

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Implements an OpenAPI Schema for JSON apis using Tapir and Circe.

Circe Decoders and Encoders are derived from the schema.


The idea for this has been in part been due to Fabio Labella's Dynosaur and I have stolen the Prism class from that repo to avoid adding a dependency to monocle. I find the apis that generate the whole OpenApi spec to be quite intrusive, so I have opted for a lesser approach.

This could, however, be expanded to include form handling, but since the apis for the different libraries/frameworks are quite different, I have opted to only handle JSON.


To use this include a dependency to:

libraryDependencies += "net.hamnaberg" %% "openapi-schema-core" % "version"  


import net.hamnaberg.schema._

case class Person(name: String, age: Int)

object Person {
  implicit val schema: Schema[Person] = Schema.record[Person] { field =>
      field[Int]("age", _.age)(Schema.boundedInt(Bound.Inclusive(0), Bound.Exclusive(150)))

import io.circe._
import io.circe.syntax._

object Main {
  def main(args: Array[String]) = {
    val json = Json.obj("name" := "Erlend", "age" := 40)
    val Right(result) = schema.decode(json)