Fixes #179

build.sbt

@@ -51,6 +51,7 @@ val exampleCases: List[ExampleCase] = List(
   ExampleCase(sampleResource("issues/issue148.yaml"), "issues.issue148"),
   ExampleCase(sampleResource("issues/issue164.yaml"), "issues.issue164"),
   ExampleCase(sampleResource("issues/issue184.yaml"), "issues.issue184"),
+  ExampleCase(sampleResource("issues/issue179.yaml"), "issues.issue179"),
   ExampleCase(sampleResource("issues/issue215.yaml"), "issues.issue215"),
   ExampleCase(sampleResource("issues/issue218.yaml"), "issues.issue218"),
   ExampleCase(sampleResource("issues/issue222.yaml"), "issues.issue222"),

modules/codegen/src/main/scala/com/twilio/guardrail/generators/Http4sHelper.scala

@@ -95,4 +95,11 @@ object Http4sHelper {
                 """
         case _             => q"EntityEncoder[F, String].contramap[$tpe](_.toString)"
       }
+
+  def generateEntityResponseGenerator(term: Term.Ref): Term =
+    q"""
+       new org.http4s.dsl.impl.EntityResponseGenerator[F,F] {
+          def status = $term
+       }
+     """
 }

modules/codegen/src/main/scala/com/twilio/guardrail/generators/Http4sServerGenerator.scala

@@ -471,9 +471,11 @@ object Http4sServerGenerator {
               case Response(statusCodeName, valueType) =>
                 val responseTerm = Term.Name(s"${statusCodeName.value}")
                 valueType.fold[Case](
-                  p"case $responseCompanionTerm.$responseTerm => ${statusCodeName}()"
+                  p"case $responseCompanionTerm.$responseTerm => F.pure(Response[F](status = org.http4s.Status.${statusCodeName}))"
                 ) { _ =>
-                  p"case $responseCompanionTerm.$responseTerm(value) => ${statusCodeName}(value)(F, ${Term.Name(s"$operationId${statusCodeName}Encoder")})"
+                  val generatorName = Term.Name(s"$operationId${statusCodeName}EntityResponseGenerator")
+                  val encoderName   = Term.Name(s"$operationId${statusCodeName}Encoder")
+                  p"case $responseCompanionTerm.$responseTerm(value) => $generatorName(value)(F,$encoderName)"
                 }
             }
             q"$handlerCall flatMap ${Term.PartialFunction(marshallers)}"
@@ -512,7 +514,7 @@ object Http4sServerGenerator {
         val routeBody = entityProcessor.fold[Term](responseInMatchInFor)(_.apply(responseInMatchInFor))
 
         val fullRoute: Case =
-          p"""case req @ $fullRouteWithTracingMatcher => 
+          p"""case req @ $fullRouteWithTracingMatcher =>
              mapRoute($operationId, req, {$routeBody})
             """
 
@@ -667,13 +669,14 @@ object Http4sServerGenerator {
                        responses: Responses[ScalaLanguage],
                        consumes: Seq[RouteMeta.ContentType],
                        produces: Seq[RouteMeta.ContentType]): List[Defn.Val] =
-      generateDecoders(operationId, bodyArgs, consumes) ++ generateEncoders(operationId, responses, produces)
+      generateDecoders(operationId, bodyArgs, consumes) ++ generateEncoders(operationId, responses, produces) ++ generateResponseGenerators(operationId,
+                                                                                                                                            responses)
 
     def generateDecoders(operationId: String, bodyArgs: Option[ScalaParameter[ScalaLanguage]], consumes: Seq[RouteMeta.ContentType]): List[Defn.Val] =
       bodyArgs.toList.flatMap {
         case ScalaParameter(_, _, _, _, argType) =>
           List(
-            q"val ${Pat.Typed(Pat.Var(Term.Name(s"${operationId}Decoder")), t"EntityDecoder[F, $argType]")} = ${Http4sHelper.generateDecoder(argType, consumes)}"
+            q"private[this] val ${Pat.Typed(Pat.Var(Term.Name(s"${operationId}Decoder")), t"EntityDecoder[F, $argType]")} = ${Http4sHelper.generateDecoder(argType, consumes)}"
           )
       }
 
@@ -683,7 +686,16 @@ object Http4sServerGenerator {
         typeDefaultPair <- response.value
         (tpe, _) = typeDefaultPair
       } yield {
-        q"val ${Pat.Var(Term.Name(s"$operationId${response.statusCodeName}Encoder"))} = ${Http4sHelper.generateEncoder(tpe, produces)}"
+        q"private[this] val ${Pat.Var(Term.Name(s"$operationId${response.statusCodeName}Encoder"))} = ${Http4sHelper.generateEncoder(tpe, produces)}"
+      }
+
+    def generateResponseGenerators(operationId: String, responses: Responses[ScalaLanguage]): List[Defn.Val] =
+      for {
+        response <- responses.value
+        if response.value.nonEmpty
+      } yield {
+        q"private[this] val ${Pat.Var(Term.Name(s"$operationId${response.statusCodeName}EntityResponseGenerator"))} = ${Http4sHelper
+          .generateEntityResponseGenerator(q"org.http4s.Status.${response.statusCodeName}")}"
       }
 
     def generateTracingExtractor(operationId: String, tracingField: Term) =

modules/codegen/src/test/scala/core/issues/Issue165.scala

@@ -55,21 +55,21 @@ class Issue165 extends FunSuite with Matchers with SwaggerSpecRunner {
               mapRoute("getRoot", req, {
                 handler.getRoot(GetRootResponse)() flatMap {
                   case GetRootResponse.Ok =>
-                    Ok()
+                    F.pure(Response[F](status = org.http4s.Status.Ok))
                 }  
               })
             case req @ GET -> Root / "foo" =>
               mapRoute("getFoo", req, {
                 handler.getFoo(GetFooResponse)() flatMap {
                   case GetFooResponse.Ok =>
-                    Ok()
+                    F.pure(Response[F](status = org.http4s.Status.Ok))
                 }
               })
             case req @ GET -> Root / "foo" / "" =>
               mapRoute("getFooDir", req, {
                 handler.getFooDir(GetFooDirResponse)() flatMap {
                   case GetFooDirResponse.Ok =>
-                    Ok()
+                    F.pure(Response[F](status = org.http4s.Status.Ok))
               }
             })
           }

modules/codegen/src/test/scala/core/issues/Issue225.scala

@@ -42,7 +42,7 @@ class Issue225 extends FunSuite with Matchers with SwaggerSpecRunner {
               mapRoute("getRoot", req, {
                 handler.getRoot(GetRootResponse)(response) flatMap {
                   case GetRootResponse.Ok =>
-                    Ok()
+                    F.pure(Response[F](status = org.http4s.Status.Ok))
                 } 
               })
           }

modules/sample/src/main/resources/issues/issue179.yaml

@@ -0,0 +1,13 @@
+swagger: '2.0'
+info:
+  title: https://github.com/twilio/guardrail/issues/179
+host: localhost:1234
+schemes:
+- http
+paths:
+  /foo:
+    get:
+      operationId: getFoo
+      responses:
+        '401':
+          description: No content