Continue refactoring Middleware (zio#1642)

* Add handle method in MiddlwareSpec

* Add toServiceSpec in API and handle method in Middleware trying out the spec usage

* Fix formatting and compilation

* Fix compile error

* Rename to implement for middlewarespec

* Fix compile errors in examples

* Fix compile time errors in example

* Try to implement toServiceSpec

* Implement combine

* More changes to Middleware

* Fix compile time errors for status

* Reformat core

* Format benchmarks

* Fix incoming of middleware

* Fix the need of asInstanceOf

* Fix peekrequest

* Make sure toHttpMiddleware works

project/Debug.scala

@@ -16,7 +16,7 @@ object Debug {
  /**
  * Sets the main application to execute in the example project.
  */
- //val Main = "zio.http.api.APIExamples"
+ // val Main = "zio.http.api.APIExamples"
  val Main = "zio.http.api.BasicAuthAPIExample"
- //val Main = "example.BasicAuth"
+ // val Main = "example.BasicAuth"
 }

project/metals.sbt

@@ -2,5 +2,5 @@
 
 // This file enables sbt-bloop to create bloop config files.
 
-addSbtPlugin("ch.epfl.scala" % "sbt-bloop" % "1.5.3")
+addSbtPlugin("ch.epfl.scala" % "sbt-bloop" % "1.5.4")
 

zio-http-benchmarks/src/main/scala-2.13/zio/http/benchmarks/ApiBenchmark.scala

@@ -92,7 +92,7 @@ class ApiBenchmark {
  .out[ExampleData]
 
  val handledUsersPosts =
- usersPosts.handle { case (userId, postId, limit) =>
+ usersPosts.implement { case (userId, postId, limit) =>
  ZIO.succeed(ExampleData(userId, postId, limit))
  }
 
@@ -211,7 +211,7 @@ class ApiBenchmark {
  RouteCodec.literal("first") /
  RouteCodec.int / "second" / RouteCodec.int / "third" / RouteCodec.int / "fourth" / RouteCodec.int / "fifth" / RouteCodec.int / "sixth" / RouteCodec.int / "seventh" / RouteCodec.int,
  )
- .handle { _ =>
+ .implement { _ =>
  ZIO.unit
  }
  .toHttpApp
@@ -325,57 +325,58 @@ class ApiBenchmark {
 
  // API DSL
 
- val broadUsers = API.get(RouteCodec.literal("users")).handle { _ => ZIO.unit }
- val broadUsersId = API.get(RouteCodec.literal("users") / RouteCodec.int).handle { _ => ZIO.unit }
- val boardUsersPosts =
- API.get(RouteCodec.literal("users") / RouteCodec.int / RouteCodec.literal("posts")).handle { _ => ZIO.unit }
- val boardUsersPostsId =
- API.get(RouteCodec.literal("users") / RouteCodec.int / RouteCodec.literal("posts") / RouteCodec.int).handle { _ =>
- ZIO.unit
+ val broadUsers = API.get(RouteCodec.literal("users")).implement { _ => ZIO.unit }
+ val broadUsersId = API.get(RouteCodec.literal("users") / RouteCodec.int).implement { _ => ZIO.unit }
+ val boardUsersPosts =
+ API.get(RouteCodec.literal("users") / RouteCodec.int / RouteCodec.literal("posts")).implement { _ => ZIO.unit }
+ val boardUsersPostsId =
+ API.get(RouteCodec.literal("users") / RouteCodec.int / RouteCodec.literal("posts") / RouteCodec.int).implement {
+ _ =>
+ ZIO.unit
  }
- val boardUsersPostsComments  =
+ val boardUsersPostsComments =
  API
  .get(
  RouteCodec.literal("users") / RouteCodec.int / RouteCodec.literal("posts") / RouteCodec.int / RouteCodec
  .literal("comments"),
  )
- .handle { _ =>
+ .implement { _ =>
  ZIO.unit
  }
- val boardUsersPostsCommentsId  =
+ val boardUsersPostsCommentsId =
  API
  .get(
  RouteCodec.literal("users") / RouteCodec.int / RouteCodec.literal("posts") / RouteCodec.int / RouteCodec
  .literal("comments") / RouteCodec.int,
  )
- .handle { _ =>
+ .implement { _ =>
  ZIO.unit
  }
- val broadPosts  = API.get(RouteCodec.literal("posts")).handle { _ => ZIO.unit }
- val broadPostsId  = API.get(RouteCodec.literal("posts") / RouteCodec.int).handle { _ => ZIO.unit }
- val boardPostsComments  =
- API.get(RouteCodec.literal("posts") / RouteCodec.int / RouteCodec.literal("comments")).handle { _ => ZIO.unit }
- val boardPostsCommentsId  =
- API.get(RouteCodec.literal("posts") / RouteCodec.int / RouteCodec.literal("comments") / RouteCodec.int).handle {
+ val broadPosts = API.get(RouteCodec.literal("posts")).implement { _ => ZIO.unit }
+ val broadPostsId = API.get(RouteCodec.literal("posts") / RouteCodec.int).implement { _ => ZIO.unit }
+ val boardPostsComments =
+ API.get(RouteCodec.literal("posts") / RouteCodec.int / RouteCodec.literal("comments")).implement { _ => ZIO.unit }
+ val boardPostsCommentsId =
+ API.get(RouteCodec.literal("posts") / RouteCodec.int / RouteCodec.literal("comments") / RouteCodec.int).implement {
  _ => ZIO.unit
  }
- val broadComments  = API.get(RouteCodec.literal("comments")).handle { _ => ZIO.unit }
- val broadCommentsId  = API.get(RouteCodec.literal("comments") / RouteCodec.int).handle { _ => ZIO.unit }
- val broadUsersComments  =
- API.get(RouteCodec.literal("users") / RouteCodec.int / RouteCodec.literal("comments")).handle { _ => ZIO.unit }
- val broadUsersCommentsId  =
- API.get(RouteCodec.literal("users") / RouteCodec.int / RouteCodec.literal("comments") / RouteCodec.int).handle {
+ val broadComments = API.get(RouteCodec.literal("comments")).implement { _ => ZIO.unit }
+ val broadCommentsId = API.get(RouteCodec.literal("comments") / RouteCodec.int).implement { _ => ZIO.unit }
+ val broadUsersComments =
+ API.get(RouteCodec.literal("users") / RouteCodec.int / RouteCodec.literal("comments")).implement { _ => ZIO.unit }
+ val broadUsersCommentsId =
+ API.get(RouteCodec.literal("users") / RouteCodec.int / RouteCodec.literal("comments") / RouteCodec.int).implement {
  _ => ZIO.unit
  }
- val boardUsersPostsCommentsReplies =
+ val boardUsersPostsCommentsReplies  =
  API
  .get(
  RouteCodec.literal("users") / RouteCodec.int / RouteCodec.literal("posts") / RouteCodec.int / RouteCodec
  .literal("comments") / RouteCodec.int / RouteCodec.literal(
  "replies",
  ),
  )
- .handle { _ =>
+ .implement { _ =>
  ZIO.unit
  }
  val boardUsersPostsCommentsRepliesId =
@@ -386,7 +387,7 @@ class ApiBenchmark {
  "replies",
  ) / RouteCodec.int,
  )
- .handle { _ =>
+ .implement { _ =>
  ZIO.unit
  }
 

zio-http-example/src/main/scala/example/APIExamples.scala

@@ -13,7 +13,7 @@ object APIExamples extends ZIOAppDefault {
  API.get(literal("users") / int).out[Int]
 
  val getUsersService =
- getUser.handle[Any, Nothing] { case (id: Int) =>
+ getUser.implement[Any, Nothing] { case (id: Int) =>
  ZIO.succeedNow(id)
  }
 
@@ -23,13 +23,20 @@ object APIExamples extends ZIOAppDefault {
  .in(query("name"))
 
  val getUserPostsService =
- getUserPosts.handle[Any, Nothing] { case (id1, query, id2) =>
+ getUserPosts.implement[Any, Nothing] { case (id1, query, id2) =>
  ZIO.debug(s"API2 RESULT parsed: users/$id1/posts/$id2?name=$query")
  }
 
- val serviceSpec = (getUser ++ getUserPosts).middleware(MiddlewareSpec.auth)
+ val middleware =
+ MiddlewareSpec.auth
 
- val app = serviceSpec.toHttpApp(getUsersService ++ getUserPostsService, Middleware.fromFunction(_ => ()))
+ // just like api.handle
+ val middlewareImpl =
+ middleware.implement(_ => ZIO.unit)
+
+ val serviceSpec = (getUser ++ getUserPosts).middleware(middleware)
+
+ val app = serviceSpec.toHttpApp(getUsersService ++ getUserPostsService, middlewareImpl)
 
  val request = Request.get(url = URL.fromString("/users/1").toOption.get)
  println(s"Looking up $request")

zio-http-example/src/main/scala/example/BasicAuthAPIExample.scala

@@ -2,6 +2,7 @@ package zio.http.api
 
 import zio._
 import zio.http._
+import zio.http.middleware.Auth
 
 object BasicAuthAPIExample extends ZIOAppDefault {
 
@@ -11,12 +12,32 @@ object BasicAuthAPIExample extends ZIOAppDefault {
  val getUser =
  API.get(literal("users") / int).out[Int]
 
- val getUsersService =
- getUser.handle[Any, Nothing] { case (id: Int) =>
+ val getUserImpl =
+ getUser.implement { case (id: Int) =>
  ZIO.succeed(id)
  }
 
- val app = getUsersService.toHttpApp
+ val authMiddleware = MiddlewareSpec.auth
+ val correlationId = MiddlewareSpec.addCorrelationId
+
+ val middleware: MiddlewareSpec[Auth.Credentials, String] =
+ MiddlewareSpec.auth ++ MiddlewareSpec.addCorrelationId
+
+ val authMiddlewareHandler: api.Middleware[Any, Nothing, Auth.Credentials, Unit] =
+ authMiddleware.implement(_ => ZIO.unit)
+
+ val correlationIdHandler: api.Middleware[Any, Nothing, Unit, String] =
+ correlationId.implement(_ => ZIO.succeed("xyz"))
+
+ val middlewareImpl: api.Middleware[Any, Nothing, Auth.Credentials, String] = {
+ // FIXME: Discuss Can also be implemented through `middleware.implement(cred => ZIO.succeed(cred.uname))` in
+ // which correlation id becomes username. Do we support this?
+ authMiddlewareHandler ++ correlationIdHandler
+ }
+
+ val serviceSpec = getUser.toServiceSpec.middleware(middleware)
+
+ val app = serviceSpec.toHttpApp(getUserImpl, middlewareImpl)
 
  val run = Server.serve(app).provide(Server.default)
 

zio-http/src/main/scala/zio/http/api/API.scala

@@ -1,6 +1,7 @@
 package zio.http.api
 
 import zio._
+import zio.http.api.CodecType.Route
 import zio.http.model.{Header, Headers, Method}
 import zio.schema._
 import zio.stream.ZStream
@@ -23,17 +24,20 @@ import zio.stacktracer.TracingImplicits.disableAutoTrace // scalafix:ok;
  * client libraries in other programming languages.
  */
 final case class API[Input, Output](
- method: Method,
- input: HttpCodec[CodecType.Route with CodecType.Header with CodecType.Body with CodecType.Query, Input],
- output: BodyCodec[Output],
+ input: HttpCodec[
+ CodecType.RequestType,
+ Input,
+ ],
+ output: HttpCodec[CodecType.ResponseType, Output],
  doc: Doc,
 ) { self =>
  type Id
 
  /**
  * Combines this API with another API.
  */
- def ++(that: API[_, _]): ServiceSpec[Unit, Unit, Id with that.Id] = ServiceSpec(self).++[that.Id](ServiceSpec(that))
+ def ++(that: API[_, _]): ServiceSpec[Unit, Unit, Id with that.Id] =
+ ServiceSpec(self).++[that.Id](ServiceSpec(that))
 
  def apply(input: Input): Invocation[Id, Input, Output] =
  Invocation(self, input)
@@ -90,7 +94,7 @@ final case class API[Input, Output](
  * convert an API into a service, you must specify a function which handles
  * the input, and returns the output.
  */
- def handle[R, E](f: Input => ZIO[R, E, Output]): Service[R, E, Id] =
+ def implement[R, E](f: Input => ZIO[R, E, Output]): Service[R, E, Id] =
  Service.HandledAPI[R, E, Input, Output, Id](self, f).withAllIds[Id]
 
  /**
@@ -109,18 +113,29 @@ final case class API[Input, Output](
  * headers of the request.
  */
  def in[Input2](
- in2: HttpCodec[CodecType.Route with CodecType.Header with CodecType.Body with CodecType.Query, Input2],
+ in2: HttpCodec[CodecType.RequestType, Input2],
  )(implicit
  combiner: Combiner[Input, Input2],
  ): API.WithId[combiner.Out, Output, Id] =
  copy(input = self.input ++ in2).withId[Id]
 
+ /**
+ * Convert API to a ServiceSpec.
+ */
+ def toServiceSpec: ServiceSpec[Unit, Unit, Id] =
+ ServiceSpec(self).middleware(MiddlewareSpec.none)
+
  /**
  * Changes the output type of the endpoint to the specified output type.
  */
  def out[Output2: Schema]: API.WithId[Input, Output2, Id] =
  copy(output = HttpCodec.Body(implicitly[Schema[Output2]])).withId[Id]
 
+ def out[Output2](out2: HttpCodec[CodecType.ResponseType, Output2])(implicit
+ combiner: Combiner[Output, Output2],
+ ): API.WithId[Input, combiner.Out, Id] =
+ copy(output = output ++ out2).withId[Id]
+
  /**
  * Changes the output type of the endpoint to be a stream of the specified
  * output type.
@@ -141,8 +156,9 @@ object API {
  * `API#in` method can be used to incrementally append additional input to the
  * definition of the API.
  */
- def delete[Input](route: RouteCodec[Input]): API[Input, Unit] =
- API(Method.DELETE, route, HttpCodec.empty, Doc.empty)
+ def delete[Input](route: RouteCodec[Input]): API[Input, Unit] = {
+ API(route ++ MethodCodec.delete, HttpCodec.empty, Doc.empty)
+ }
 
  /**
  * Constructs an API for a GET endpoint, given the specified input. It is not
@@ -151,7 +167,7 @@ object API {
  * definition of the API.
  */
  def get[Input](route: RouteCodec[Input]): API[Input, Unit] =
- API(Method.GET, route, HttpCodec.empty, Doc.empty)
+ API(route ++ MethodCodec.get, HttpCodec.empty, Doc.empty)
 
  /**
  * Constructs an API for a POST endpoint, given the specified input. It is not
@@ -160,7 +176,7 @@ object API {
  * definition of the API.
  */
  def post[Input](route: RouteCodec[Input]): API[Input, Unit] =
- API(Method.POST, route, HttpCodec.empty, Doc.empty)
+ API(route ++ MethodCodec.post, HttpCodec.empty, Doc.empty)
 
  /**
  * Constructs an API for a PUT endpoint, given the specified input. It is not
@@ -169,5 +185,5 @@ object API {
  * definition of the API.
  */
  def put[Input](route: RouteCodec[Input]): API[Input, Unit] =
- API(Method.PUT, route, HttpCodec.empty, Doc.empty)
+ API(route ++ MethodCodec.put, HttpCodec.empty, Doc.empty)
 }

zio-http/src/main/scala/zio/http/api/CodecType.scala

@@ -1,9 +1,15 @@
 package zio.http.api
 
 sealed trait CodecType
+
 object CodecType {
+ type RequestType <: Route with Body with Query with Header with Method
+ type ResponseType <: Body with Header with Status
+
  type Route <: CodecType
  type Body <: CodecType
  type Query <: CodecType
  type Header <: CodecType
+ type Method <: CodecType
+ type Status <: CodecType
 }

zio-http/src/main/scala/zio/http/api/HttpCodec.scala

@@ -1,7 +1,8 @@
 package zio.http.api
 
-import scala.language.implicitConversions
+import zio.http.URL
 
+import scala.language.implicitConversions
 import zio.stream.ZStream
 import zio.schema.Schema
 import zio.stacktracer.TracingImplicits.disableAutoTrace // scalafix:ok;
@@ -55,6 +56,12 @@ sealed trait HttpCodec[-AtomTypes, Input] {
  def transform[Input2](f: Input => Input2, g: Input2 => Input): HttpCodec[AtomTypes, Input2] =
  HttpCodec.TransformOrFail[AtomTypes, Input, Input2](self, in => Right(f(in)), output => Right(g(output)))
 
+ def transformOrFail[Input2](
+ f: Input => Either[String, Input2],
+ g: Input2 => Either[String, Input],
+ ): HttpCodec[AtomTypes, Input2] =
+ HttpCodec.TransformOrFail[AtomTypes, Input, Input2](self, f, g)
+
  def transformOrFailLeft[Input2](
  f: Input => Either[String, Input2],
  g: Input2 => Input,
@@ -77,12 +84,14 @@ object HttpCodec extends HeaderCodecs with QueryCodecs with RouteCodecs {
 
  private[api] sealed trait Atom[-AtomTypes, Input0] extends HttpCodec[AtomTypes, Input0]
 
- private[api] case object Empty extends Atom[Any, Unit]
- private[api] final case class Route[A](textCodec: TextCodec[A]) extends Atom[CodecType.Route, A]
- private[api] final case class Body[A](input: Schema[A]) extends Atom[CodecType.Body, A]
+ private[api] case object Empty extends Atom[Any, Unit]
+ private[api] final case class Status[A](textCodec: TextCodec[A]) extends Atom[CodecType.Status, A]
+ private[api] final case class Route[A](textCodec: TextCodec[A]) extends Atom[CodecType.Route, A]
+ private[api] final case class Body[A](input: Schema[A]) extends Atom[CodecType.Body, A]
  private[api] final case class BodyStream[A](element: Schema[A])
  extends Atom[CodecType.Body, ZStream[Any, Throwable, A]] // and delete Out
  private[api] final case class Query[A](name: String, textCodec: TextCodec[A]) extends Atom[CodecType.Query, A]
+ private[api] final case class Method[A](methodCodec: TextCodec[A]) extends Atom[CodecType.Method, A]
  private[api] final case class Header[A](name: String, textCodec: TextCodec[A]) extends Atom[CodecType.Header, A]
  private[api] final case class IndexedAtom[AtomType, A](atom: Atom[AtomType, A], index: Int) extends Atom[AtomType, A]
  private[api] final case class WithDoc[AtomType, A](in: HttpCodec[AtomType, A], doc: Doc)

zio-http/src/main/scala/zio/http/api/MethodCodec.scala

@@ -0,0 +1,3 @@
+package zio.http.api
+
+object MethodCodec extends MethodCodecs

zio-http/src/main/scala/zio/http/api/MethodCodecs.scala

@@ -0,0 +1,14 @@
+package zio.http.api
+
+import zio.http.api.CodecType.Method
+
+private[api] trait MethodCodecs {
+ def method(method: zio.http.model.Method): HttpCodec[CodecType.Method, Unit] =
+ HttpCodec.Method(TextCodec.constant(method.toString()))
+
+ def get: HttpCodec[Method, Unit] = method(zio.http.model.Method.GET)
+ def put: HttpCodec[Method, Unit] = method(zio.http.model.Method.PUT)
+ def post: HttpCodec[Method, Unit] = method(zio.http.model.Method.POST)
+ def delete: HttpCodec[Method, Unit] = method(zio.http.model.Method.DELETE)
+
+}