Head request empty body - series/0.17 (#1149)

* handle head requests with empty body * remove content length header * fix comparison
disneystreaming · Aug 14, 2023 · 39fb372 · 39fb372
1 parent f001a5e
commit 39fb372
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Showing 4 changed files with 51 additions and 2 deletions.
diff --git a/modules/http4s/src/smithy4s/http4s/internals/SmithyHttp4sServerEndpoint.scala b/modules/http4s/src/smithy4s/http4s/internals/SmithyHttp4sServerEndpoint.scala
@@ -33,6 +33,7 @@ import smithy4s.schema.Alt
 import smithy4s.kinds._
 import org.http4s.HttpApp
 import org.typelevel.vault.Key
+import org.typelevel.ci.CIString
 
 /**
   * A construct that encapsulates a smithy4s endpoint, and exposes
@@ -104,6 +105,18 @@ private[http4s] class SmithyHttp4sServerEndpointImpl[F[_], Op[_, _, _, _, _], I,
     httpEndpoint.matches(path)
   }
 
+  private val headRemoveBody: Response[F] => Response[F] =
+    if (endpoint.hints.get[smithy.api.Http].exists(_.method.value === "HEAD"))
+      r =>
+        r.withHeaders(
+          r.headers.headers.filterNot(h =>
+            h.name === CIString("Content-Type") || h.name === CIString(
+              "Content-Length"
+            )
+          )
+        ).withBodyStream(fs2.Stream.empty)
+    else identity
+
   override val httpApp: HttpApp[F] = {
     val baseApp = HttpApp[F] { req =>
       val pathParams = req.attributes.lookup(pathParamsKey).getOrElse(Map.empty)
@@ -114,7 +127,7 @@ private[http4s] class SmithyHttp4sServerEndpointImpl[F[_], Op[_, _, _, _, _], I,
         output <- (impl(endpoint.wrap(input)): F[O])
       } yield output
 
-      run.map(successResponse)
+      run.map(successResponse).map(headRemoveBody)
     }
     middleware(endpoint)(baseApp).handleErrorWith(error =>
       Kleisli.liftF(errorResponse(error))

diff --git a/modules/tests/src/smithy4s/tests/PizzaAdminServiceImpl.scala b/modules/tests/src/smithy4s/tests/PizzaAdminServiceImpl.scala
@@ -117,4 +117,7 @@ class PizzaAdminServiceImpl(ref: Compat.Ref[IO, State])
       body: EchoBody,
       queryParam: Option[String]
   ): IO[Unit] = IO.unit
+
+  def headRequest(): cats.effect.IO[HeadRequestOutput] =
+    IO.pure(HeadRequestOutput("test"))
 }
diff --git a/modules/tests/src/smithy4s/tests/PizzaSpec.scala b/modules/tests/src/smithy4s/tests/PizzaSpec.scala
@@ -312,6 +312,27 @@ abstract class PizzaSpec
     )
   }
 
+  routerTest("HEAD request should have empty body") { (client, uri, log) =>
+    for {
+      res <- client.send[String](
+        HEAD((uri / "head-request")),
+        log
+      )
+    } yield {
+      val (code, headers, body) = res
+      expect.same(code, 200) &&
+      expect.same(body, "") &&
+      expect.same(
+        headers,
+        HeaderMap(
+          Map(
+            CaseInsensitive("Test") -> List("test")
+          )
+        )
+      )
+    }
+  }
+
   pureTest("Negative: http no match (bad path)") {
     val matchResult = smithy4s.http.httpMatch(
       PizzaAdminService.service,

diff --git a/sampleSpecs/pizza.smithy b/sampleSpecs/pizza.smithy
@@ -7,7 +7,7 @@ use alloy#simpleRestJson
 @simpleRestJson
 service PizzaAdminService {
   version: "1.0.0",
-  operations: [AddMenuItem, GetMenu, Version, Health, HeaderEndpoint, RoundTrip, GetEnum, GetIntEnum, CustomCode, Book, Echo]
+  operations: [AddMenuItem, GetMenu, Version, Health, HeaderEndpoint, RoundTrip, GetEnum, GetIntEnum, CustomCode, Book, Echo, HeadRequest]
 }
 
 @http(method: "POST", uri: "/restaurant/{restaurant}/menu/item", code: 201)
@@ -336,3 +336,15 @@ structure EchoBody {
   @length(min: 10)
   data: String
 }
+
+@http(method: "HEAD", uri: "/head-request")
+@readonly
+operation HeadRequest {
+    output: HeadRequestOutput
+}
+
+structure HeadRequestOutput {
+    @httpHeader("Test")
+    @required
+    test: String
+}