With tapir you can describe HTTP API endpoints as immutable Scala values. Each endpoint can contain a number of input parameters, error-output parameters, and normal-output parameters. An endpoint specification can be interpreted as:
- a server, given the "business logic": a function, which computes output parameters based on input parameters. Currently supported:
- a client, which is a function from input parameters to output parameters. Currently supported: sttp.
- documentation. Currently supported: OpenAPI.
Tapir is licensed under Apache2, the source code is available of GitHub.
Depending on how you prefer to explore the library, take a look at one of the examples or read on for a more detailed description of how tapir works!
import sttp.tapir._
import sttp.tapir.json.circe._
import io.circe.generic.auto._
type Limit = Int
type AuthToken = String
case class BooksFromYear(genre: String, year: Int)
case class Book(title: String)
val booksListing: Endpoint[(BooksFromYear, Limit, AuthToken), String, List[Book], Nothing] =
endpoint
.get
.in(("books" / path[String]("genre") / path[Int]("year")).mapTo(BooksFromYear))
.in(query[Limit]("limit").description("Maximum number of books to retrieve"))
.in(header[AuthToken]("X-Auth-Token"))
.errorOut(stringBody)
.out(jsonBody[List[Book]])
//
import sttp.tapir.docs.openapi._
import sttp.tapir.openapi.circe.yaml._
val docs = booksListing.toOpenAPI("My Bookshop", "1.0")
println(docs.toYaml)
//
import sttp.tapir.server.akkahttp._
import akka.http.scaladsl.server.Route
import scala.concurrent.Future
def bookListingLogic(bfy: BooksFromYear,
limit: Limit,
at: AuthToken): Future[Either[String, List[Book]]] =
Future.successful(Right(List(Book("The Sorrows of Young Werther"))))
val booksListingRoute: Route = booksListing.toRoute(bookListingLogic _)
//
import sttp.tapir.client.sttp._
import com.softwaremill.sttp._
val booksListingRequest: Request[Either[String, List[Book]], Nothing] = booksListing
.toSttpRequest(uri"http://localhost:8080")
.apply(BooksFromYear("SF", 2016), 20, "xyz-abc-123")
sttp is a family of Scala HTTP-related projects, and currently includes:
- sttp client: the Scala HTTP client you always wanted!
- sttp tapir: this project
- sttp model: simple HTTP model classes (used by client & tapir)
Development and maintenance of sttp tapir is sponsored by SoftwareMill, a software development and consulting company. We help clients scale their business through software. Our areas of expertise include backends, distributed systems, blockchain, machine learning and data analytics.
.. toctree::
:maxdepth: 2
:caption: Getting started
quickstart
examples
goals
.. toctree::
:maxdepth: 2
:caption: Endpoints
endpoint/basics
endpoint/ios
endpoint/statuscodes
endpoint/codecs
endpoint/customtypes
endpoint/validation
endpoint/json
endpoint/forms
endpoint/auth
.. toctree::
:maxdepth: 2
:caption: Server interpreters
server/akkahttp
server/http4s
server/finatra
server/options
server/logic
server/errors
server/debugging
.. toctree::
:maxdepth: 2
:caption: Client interpreters
sttp
.. toctree::
:maxdepth: 2
:caption: Documentation interpreters
openapi
.. toctree::
:maxdepth: 2
:caption: Other subjects
other_interpreters
mytapir
contributing