fix: Include metadata in StatusRuntimeException (#1906)

Author: jtjeferreira

runtime/src/main/scala/akka/grpc/internal/AkkaHttpClientUtils.scala

@@ -14,9 +14,10 @@ import akka.annotation.InternalApi
 import akka.event.LoggingAdapter
 import akka.grpc.GrpcProtocol.GrpcProtocolReader
 import akka.grpc.{ GrpcClientSettings, GrpcResponseMetadata, GrpcSingleResponse, ProtobufSerializer }
+import akka.grpc.scaladsl.StringEntry
 import akka.http.scaladsl.model.HttpEntity.{ Chunk, Chunked, LastChunk, Strict }
 import akka.http.scaladsl.{ ClientTransport, ConnectionContext, Http }
-import akka.http.scaladsl.model.{ AttributeKey, HttpHeader, HttpRequest, HttpResponse, RequestResponseAssociation, Uri }
+import akka.http.scaladsl.model._
 import akka.http.scaladsl.settings.ClientConnectionSettings
 import akka.stream.{ Materializer, OverflowStrategy }
 import akka.stream.scaladsl.{ Keep, Sink, Source }
@@ -220,7 +221,11 @@ object AkkaHttpClientUtils {
                         .watchTermination()((_, done) =>
                           done.onComplete(_ => trailerPromise.trySuccess(immutable.Seq.empty)))
                     case Strict(_, data) =>
-                      trailerPromise.success(immutable.Seq.empty)
+                      val rawTrailers = response.attribute(AttributeKeys.trailer).map(_.headers).getOrElse(Seq.empty)
+                      val trailers = rawTrailers.map(h => HttpHeader.parse(h._1, h._2)).collect {
+                        case HttpHeader.ParsingResult.Ok(header, _) => header
+                      }
+                      trailerPromise.success(trailers)
                       Source.single[ByteString](data)
                     case _ =>
                       response.entity.discardBytes()
@@ -281,19 +286,21 @@ object AkkaHttpClientUtils {
       response: HttpResponse,
       trailers: Seq[HttpHeader]): StatusRuntimeException = {
     val allHeaders = response.headers ++ trailers
+    val metadata: io.grpc.Metadata =
+      new MetadataImpl(allHeaders.map(h => (h.name, StringEntry(h.value))).toList).toGoogleGrpcMetadata()
     allHeaders.find(_.name == "grpc-status").map(_.value) match {
       case None =>
-        new StatusRuntimeException(
-          mapHttpStatus(response)
-            .withDescription("No grpc-status found")
-            .augmentDescription(s"When calling rpc service: ${requestUri.toString()}"))
+        val status = mapHttpStatus(response)
+          .withDescription("No grpc-status found")
+          .augmentDescription(s"When calling rpc service: ${requestUri.toString()}")
+        new StatusRuntimeException(status, metadata)
       case Some(statusCode) =>
         val description = allHeaders.find(_.name == "grpc-message").map(_.value)
-        new StatusRuntimeException(
-          Status
-            .fromCodeValue(statusCode.toInt)
-            .withDescription(description.orNull)
-            .augmentDescription(s"When calling rpc service: ${requestUri.toString()}"))
+        val status = Status
+          .fromCodeValue(statusCode.toInt)
+          .withDescription(description.orNull)
+          .augmentDescription(s"When calling rpc service: ${requestUri.toString()}")
+        new StatusRuntimeException(status, metadata)
     }
   }
 

runtime/src/test/scala/akka/grpc/internal/AkkaHttpClientUtilsSpec.scala

@@ -7,14 +7,13 @@ package akka.grpc.internal
 import scala.concurrent.Future
 import scala.concurrent.duration._
 import akka.actor.ActorSystem
+import akka.http.scaladsl.model._
 import akka.http.scaladsl.model.HttpEntity.Strict
-import akka.http.scaladsl.model.HttpResponse
 import akka.http.scaladsl.model.StatusCodes._
-import akka.http.scaladsl.model.Uri
 import akka.http.scaladsl.model.headers.RawHeader
 import akka.testkit.TestKit
 import akka.util.ByteString
-import io.grpc.{ Status, StatusRuntimeException }
+import io.grpc.{ Metadata, Status, StatusRuntimeException }
 import org.scalatest.concurrent.ScalaFutures
 import org.scalatest.matchers.should.Matchers
 import org.scalatest.time.Span
@@ -41,12 +40,35 @@ class AkkaHttpClientUtilsSpec extends TestKit(ActorSystem()) with AnyWordSpecLik
 
     "map a strict 200 response with non-0 gRPC error code to a failed stream" in {
       val requestUri = Uri("https://example.com/GuestExeSample/GrpcHello")
+      val responseHeaders = List(RawHeader("grpc-status", "9"), RawHeader("custom-key", "custom-value-in-header"))
+      val response =
+        Future.successful(HttpResponse(OK, responseHeaders, Strict(GrpcProtocolNative.contentType, ByteString.empty)))
+      val source = AkkaHttpClientUtils.responseToSource(requestUri, response, null, false)
+
+      val failure = source.run().failed.futureValue
+      failure.asInstanceOf[StatusRuntimeException].getStatus.getCode should be(Status.Code.FAILED_PRECONDITION)
+      failure.asInstanceOf[StatusRuntimeException].getTrailers.get(key) should be("custom-value-in-header")
+    }
+
+    "map a strict 200 response with non-0 gRPC error code with a trailer to a failed stream with trailer metadata" in {
+      val requestUri = Uri("https://example.com/GuestExeSample/GrpcHello")
+      val responseHeaders = List(RawHeader("grpc-status", "9"))
+      val responseTrailers = Trailer(RawHeader("custom-key", "custom-trailer-value") :: Nil)
       val response = Future.successful(
-        HttpResponse(OK, List(RawHeader("grpc-status", "9")), Strict(GrpcProtocolNative.contentType, ByteString.empty)))
+        new HttpResponse(
+          OK,
+          responseHeaders,
+          Map.empty[AttributeKey[_], Any].updated(AttributeKeys.trailer, responseTrailers),
+          Strict(GrpcProtocolNative.contentType, ByteString.empty),
+          HttpProtocols.`HTTP/1.1`))
       val source = AkkaHttpClientUtils.responseToSource(requestUri, response, null, false)
 
       val failure = source.run().failed.futureValue
       failure.asInstanceOf[StatusRuntimeException].getStatus.getCode should be(Status.Code.FAILED_PRECONDITION)
+      failure.asInstanceOf[StatusRuntimeException].getTrailers should not be null
+      failure.asInstanceOf[StatusRuntimeException].getTrailers.get(key) should be("custom-trailer-value")
     }
+
+    lazy val key = Metadata.Key.of("custom-key", Metadata.ASCII_STRING_MARSHALLER)
   }
 }