=htp #20648 encoder now encodes all response types, not only successes (#20691)

* #20648 encoder now encodes all response types, not only successes

* #20648 fix by autoformatter

akka-http-tests/src/test/scala/akka/http/scaladsl/server/directives/CodingDirectivesSpec.scala

@@ -33,6 +33,10 @@ class CodingDirectivesSpec extends RoutingSpec with Inside {
   lazy val helloGzipped = compress("Hello", Gzip)
   lazy val helloDeflated = compress("Hello", Deflate)
 
+  val nope = complete((404, "Nope!"))
+  lazy val nopeGzipped = compress("Nope!", Gzip)
+  lazy val nopeDeflated = compress("Nope!", Deflate)
+
   "the NoEncoding decoder" should {
     "decode the request content if it has encoding 'identity'" in {
       Post("/", "yes") ~> `Content-Encoding`(identity) ~> {
@@ -161,6 +165,19 @@ class CodingDirectivesSpec extends RoutingSpec with Inside {
     }
   }
 
+  "the encoder" should {
+    "encode the response content with GZIP if the response is not a success and request has no Accept-Encoding header" in {
+      Post() ~> {
+        encodeResponseWith(Gzip) { nope }
+      } ~> check { strictify(responseEntity) shouldEqual HttpEntity(ContentType(`text/plain`, `UTF-8`), nopeGzipped) }
+    }
+    "encode the response content with Deflate if the response is not a success and request has no Accept-Encoding header" in {
+      Post() ~> {
+        encodeResponseWith(Deflate) { nope }
+      } ~> check { strictify(responseEntity) shouldEqual HttpEntity(ContentType(`text/plain`, `UTF-8`), nopeDeflated) }
+    }
+  }
+
   "the Gzip encoder" should {
     "encode the response content with GZIP if the client accepts it with a dedicated Accept-Encoding header" in {
       Post() ~> `Accept-Encoding`(gzip) ~> {

akka-http-tests/src/test/scala/akka/http/scaladsl/server/directives/ExecutionDirectivesSpec.scala

@@ -5,10 +5,13 @@
 package akka.http.scaladsl.server
 package directives
 
-import akka.http.scaladsl.model.{ MediaTypes, MediaRanges, StatusCodes }
+import akka.http.scaladsl.coding.Gzip
+import akka.http.scaladsl.model._
+import akka.http.scaladsl.model.headers.HttpEncodings._
 import akka.http.scaladsl.model.headers._
 import scala.concurrent.Future
 import akka.testkit.EventFilter
+import org.scalatest.matchers.Matcher
 
 class ExecutionDirectivesSpec extends RoutingSpec {
   object MyException extends RuntimeException
@@ -96,9 +99,39 @@ class ExecutionDirectivesSpec extends RoutingSpec {
     }
   }
 
+  "The `handleRejections` directive" should {
+    "handle encodeResponse inside RejectionHandler for non-success responses" in {
+      val rejectionHandler: RejectionHandler = RejectionHandler.newBuilder()
+        .handleNotFound {
+          encodeResponseWith(Gzip) {
+            complete((404, "Not here!"))
+          }
+        }.result()
+
+      Get("/hell0") ~>
+        get {
+          handleRejections(rejectionHandler) {
+            encodeResponseWith(Gzip) {
+              path("hello") {
+                get {
+                  complete(HttpEntity(ContentTypes.`text/plain(UTF-8)`, "world"))
+                }
+              }
+            }
+          }
+        } ~> check {
+          response should haveContentEncoding(gzip)
+          status shouldEqual StatusCodes.NotFound
+        }
+    }
+  }
+
   def exceptionShouldBeHandled(route: Route) =
     Get("/abc") ~> route ~> check {
       status shouldEqual StatusCodes.InternalServerError
       responseAs[String] shouldEqual "Pling! Plong! Something went wrong!!!"
     }
+
+  def haveContentEncoding(encoding: HttpEncoding): Matcher[HttpResponse] =
+    be(Some(`Content-Encoding`(encoding))) compose { (_: HttpResponse).header[`Content-Encoding`] }
 }

akka-http/src/main/scala/akka/http/scaladsl/coding/Encoder.scala

@@ -43,10 +43,7 @@ trait Encoder {
 }
 
 object Encoder {
-  val DefaultFilter: HttpMessage ⇒ Boolean = {
-    case req: HttpRequest                    ⇒ isCompressible(req)
-    case res @ HttpResponse(status, _, _, _) ⇒ isCompressible(res) && status.isSuccess
-  }
+  val DefaultFilter: HttpMessage ⇒ Boolean = isCompressible _
   private[coding] def isCompressible(msg: HttpMessage): Boolean =
     msg.entity.contentType.mediaType.isCompressible