Generate endpoint definitions from an OpenAPI YAML

Note

This is a really early alpha implementation.

Installation steps

Add the sbt plugin to the project/plugins.sbt:

addSbtPlugin("com.softwaremill.sttp.tapir" % "sbt-openapi-codegen" % "1.7.3")

Enable the plugin for your project in the build.sbt:

enablePlugins(OpenapiCodegenPlugin)

Add your OpenApi file to the project, and override the openapiSwaggerFile setting in the build.sbt:

openapiSwaggerFile := baseDirectory.value / "swagger.yaml"

At this point your compile step will try to generate the endpoint definitions to the sttp.tapir.generated.TapirGeneratedEndpoints object, where you can access the defined case-classes and endpoint definitions.

Usage and options

The generator currently supports these settings, you can override them in the build.sbt;

setting	default value	description
openapiSwaggerFile	baseDirectory.value / “swagger.yaml”	The swagger file with the api definitions.
openapiPackage	sttp.tapir.generated	The name for the generated package.
openapiObject	TapirGeneratedEndpoints	The name for the generated object.

The general usage is;

import sttp.apispec.openapi.circe.yaml._
import sttp.tapir.generated._
import sttp.tapir.docs.openapi._

val docs = TapirGeneratedEndpoints.generatedEndpoints.toOpenAPI("My Bookshop", "1.0")

Limitations

Currently, the generated code depends on "io.circe" %% "circe-generic". In the future probably we will make the encoder/decoder json lib configurable (PRs welcome).

String-like enums in Scala 2 depend on both "com.beachape" %% "enumeratum" and "com.beachape" %% "enumeratum-circe". For Scala 3 we derive native enums, and depend instead on "org.latestbit" %% "circe-tagged-adt-codec". Other forms of OpenApi enum are not currently supported.

We currently miss a lot of OpenApi features like:

• tags

• ADTs

• missing model types and meta descriptions (like date, minLength)

• file handling