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    Update sbt-scalajs, scalajs-lib… Disable 2.11 for JS & native Merge branch 'master' into upda… and 2 more (compare)

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    adamw on sbt-scalajs-1.13.0

    Disable 2.11 for JS & native (compare)


Hello ! I'm trying to use sttp with ZIO backend (2.2.4)but I end up having a runtime exception

─An unchecked error was produced.
║ java.lang.IncompatibleClassChangeError: Found interface zio.ZQueue, but class was expected
║       at zio.interop.reactivestreams.Adapters$.process(Adapters.scala:71)
║       at zio.interop.reactivestreams.Adapters$.$anonfun$publisherToStream$6(Adapters.scala:49)
║       at zio.ZManaged.$anonfun$flatMap$6(ZManaged.scala:315)
║       at zio.internal.FiberContext.evaluateNow(FiberContext.scala:815)
║       at zio.internal.FiberContext.$anonfun$evaluateLater$1(FiberContext.scala:687)
║       at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
║       at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
║       at java.lang.Thread.run(Thread.java:748)

I can't figure out why this is happening, does someone have any clue ? I unfortunately can't share the code but it's a really simple POST request I'm trying to make, followed by a Runtime.default.unsafeRunToFuture

1 reply
Esenbaev Nursultan

Hello, everyone!
Got this error

value mapK is not a member of sttp.client.SttpBackend


I've imported import sttp.client.impl.cats.implicits._
but it doesn't help.

7 replies
Adam Warski
hey :) we've released sttp-client 3.0.0-RC1, feedback or further suggestions on improvements would be most welcome! https://blog.softwaremill.com/whats-coming-up-in-sttp-client-3-30d01ab42d1b
2 replies
Kamil Kloch
Hello all, how to convert org.scalajs.dom.raw.File to sttp.client.dom.experimental.File? In other words, I would like to use a platform-agnostic method upload(file: SttpFile) and on the JS side all I have is a org.scalajs.dom.raw.File. Thanks!
Kamil Kloch
This ugly workaround works, any other ideas? SttpFile.fromDomFile(f.asInstanceOf[sttp.client.dom.experimental.File])
2 replies
Yann Moisan

Hi. I'm migrating from sttp v1 to sttp v2. I use a tagless final approach. In order to map on a Response, I was using

implicit val monad: MonadError[R] = backend.responseMonad

in v2, it doesn't work anymore.
Do I have to declare a context bound instead R[_]: Functor

6 replies
Yann Moisan

Hello. I've seen the logging backend in sttp v2. It's always nice to be able to remove some boilerplate in my code.

How can I log also the body of a response ?

The simplest way I found is to extend the Slf4jLoggingListener :

(I need to be in this package because Logger is private)

package sttp.client.logging.slf4j

import sttp.client.listener.ListenerBackend
import sttp.client.logging.LogMessages.requestToString
import sttp.client.{Identity, Request, Response, SttpBackend}

object CustomSlf4jLoggingListener {
  private val logger = new Logger("sttp.client.logging.slf4j.Slf4jLoggingBackend")

  def apply[F[_], S, WS_HANDLER[_]](
      delegate: SttpBackend[F, S, WS_HANDLER]
  ): SttpBackend[F, S, WS_HANDLER] =
    ListenerBackend.lift(delegate, new CustomSlf4jLoggingListener(logger))

class CustomSlf4jLoggingListener(logger: Logger) extends Slf4jLoggingListener(logger) {
  override def requestSuccessful(
      request: Request[_, _],
      response: Response[_],
      tag: Unit
  ): Identity[Unit] =
    if (response.isSuccess) {
      logger.debug(response_(request, response))
    } else {
      logger.warn(response_(request, response))

  def response_(request: Request[_, _], response: Response[_]): String =
    s"For request: ${requestToString(request)}, got response: ${responseToString(response)}"

  def responseToString(response: Response[_]): String =
    s"${response.code}, body: ${response.body}"
2 replies

Hi All, I am new to sttp and trying to learn few basics of it.
In one of the issues I am facing I have not been getting right json response for this code

val baseRequest: RequestT[Empty, Either[String, String], Nothing] = basicRequest.header("accept", "application/vnd.github.v3+json")
    val url: Uri = uri"https://api.github.com/events"

      .send {
          .response(asJson[Either[GitErrorResponse, List[CommitEvent]]])
      .map[Either[Error, List[CommitEvent]]] {
        response: Response[Either[ResponseError[CirceError], Either[GitErrorResponse, List[CommitEvent]]]] =>
      .handleError { throwable: Throwable =>

compare that to this basic scala code its working as expected

val url = "https://api.github.com/events"
  val result = scala.io.Source.fromURL(url).mkString

Can someone help ?

1 reply
Hi everyone, anyway here has some experience with opening a websocket connection with a custom protocol?
15 replies
Hi there. Is there any configuration for connection pools for okhttp backend?
2 replies
Łukasz Drygała
Hi everyone, is there any way to convert org.scalajs.dom.File into sttp.client.dom.experimental.File. I wanted to send a file selected from UI.
11 replies
Glen Marchesani
@adamw is there a place that talks about the differences between v2 and v3 aka the what's new ? thanks
4 replies
Glen Marchesani
also thank you, thank you, thank you for having a new package name for v3 (other projects that didn't do that have caused my organization a fair bit of chaos) so it is appreciated.
Glen Marchesani
Has anyone gotten sttp working with sse / server sent events ? I plan to use the streaming support to do it
3 replies
This message was deleted
Mark Hammons
Is there ever a situation where sttp will attempt to reread a stream body?
19 replies
Hi @adamw, I'm getting around to finally try out sttp3 and I'm having problem with migrating fromMetadata to the new signature. Can you provide an example for the new signature?
v2's signature is: def fromMetadata[T, S](f: ResponseMetadata => ResponseAs[T, S]): ResponseAs[T, S]
v3's is: def fromMetadata[T, R](default: ResponseAs[T, R], conditions: ConditionalResponseAs[T, R]*)
14 replies
Aleksandar Skrbic
    val request = basicRequest

    retry.Backoff(5, 1.second).apply(request.send())
4th line throws this error
java.lang.NoSuchMethodError: sttp.client.ResponseAs$.deserializeRightWithError(Lscala/Function1;)Lscala/Function1;
Does anyone know what could be a problem? I have implicit Decoder for AccessToken
I'm using AkkaHttpBackend
@adamw why tapir 0.17.0-M2 brings sttp3 with package name sttp.client3 when sync-http-client-backend-cats 3.0.0-RC3 uses sttp3 with package name sttp.client? How should I compose them? ;)
In the end I have such an error:
inferred type arguments [mypackage.AppEffect,sttp.client.SttpBackend[mypackage.AppEffect,Any]] do not conform to method fromEffect's type parameter bounds [F[_],I <: sttp.client3.SttpBackend[mypackage.AppEffect,Any]]
2 replies
Aleksandar Skrbic

java.lang.NoSuchMethodError: sttp.client.ResponseAs$.deserializeRightWithError(Lscala/Function1;)Lscala/Function1;

I've managed to solve this. I had different versions of sttp and sttp-akka-http backend so that was the problem :)

Glen Marchesani
so I am getting EventSource (aka server sent events) working in scala js and scala jvm. We had a bunch of weird issues where the scala js code worked but not as expected (things like EventStream in chrome wasn't populated). That Chrome symptom says that you are not using a polyfill and not EventSource directly. We are like but we are using EventSource. The end of the story is it turns out we were using our scala jvm based server sent events parser with sttp's monix fetch backed in the brower and it just worked...
1 reply
nobody noticed this for a long long time
Hello, im getting this weird compilation errors while moving from POM to SBT(sttp v. 1.7.2)
"No implicits found for parameter handler: SttpHandler[R_, Nothing]"
I have sync backend implicit in scope. Maybe i'm missing some compiler flag or something?
2 replies
Tobias Roeser
Hello, can anybody tell me where the * in class AkkaHttpBackend extends SttpBackend[Future, Source[ByteString, Any], Flow[Message, Message, *]] comes from?
6 replies
IJ IDEA can't
Denis Mikhaylov
Hi! Does anyone know any sttp benchmarks with backend comparison? Or maybe someone compared Java 11 HttpClient with Netty?
Glen Marchesani
is there something I need to do to cleanup resources on errors ? I have a sttp client request that is failing because the server isn't started after a little bit I get a java.io.IOException: Too many open files and at that point it never recovers
this is in an isolated use case so there is nothing else using up descriptors
the full stack trace is
17:58:15.191 | ERROR | scala-execution-context-global-14 | a8.hermes.ServerSentEventsFactory. | error with stream will restart @ Some(30)
java.lang.IllegalStateException: failed to create a child event loop
  at io.netty.util.concurrent.MultithreadEventExecutorGroup.<init>(MultithreadEventExecutorGroup.java:88)
  at io.netty.util.concurrent.MultithreadEventExecutorGroup.<init>(MultithreadEventExecutorGroup.java:58)
  at io.netty.util.concurrent.MultithreadEventExecutorGroup.<init>(MultithreadEventExecutorGroup.java:47)
  at io.netty.channel.MultithreadEventLoopGroup.<init>(MultithreadEventLoopGroup.java:59)
  at io.netty.channel.nio.NioEventLoopGroup.<init>(NioEventLoopGroup.java:86)
  at io.netty.channel.nio.NioEventLoopGroup.<init>(NioEventLoopGroup.java:81)
  at io.netty.channel.nio.NioEventLoopGroup.<init>(NioEventLoopGroup.java:68)
  at org.asynchttpclient.netty.channel.NioTransportFactory.newEventLoopGroup(NioTransportFactory.java:32)
  at org.asynchttpclient.netty.channel.NioTransportFactory.newEventLoopGroup(NioTransportFactory.java:21)
  at org.asynchttpclient.netty.channel.ChannelManager.<init>(ChannelManager.java:133)
  at org.asynchttpclient.DefaultAsyncHttpClient.<init>(DefaultAsyncHttpClient.java:92)
  at sttp.client.asynchttpclient.AsyncHttpClientBackend$.defaultClient(AsyncHttpClientBackend.scala:380)
  at sttp.client.asynchttpclient.monix.AsyncHttpClientMonixBackend$.$anonfun$apply$1(AsyncHttpClientMonixBackend.scala:76)
  at monix.eval.internal.TaskRunLoop$.startLight(TaskRunLoop.scala:271)
  at monix.eval.Task.runAsyncOptF(Task.scala:812)
  at monix.eval.Task.runAsyncOpt(Task.scala:710)
  at monix.eval.Task.runAsync(Task.scala:660)
  at monix.reactive.internal.builders.TaskAsObservable.unsafeSubscribeFn(TaskAsObservable.scala:30)
  at monix.reactive.internal.operators.ConcatMapObservable.unsafeSubscribeFn(ConcatMapObservable.scala:76)
  at monix.reactive.internal.operators.OnErrorRecoverWithObservable.unsafeSubscribeFn(OnErrorRecoverWithObservable.scala:35)
  at monix.reactive.internal.operators.LiftByOperatorObservable.unsafeSubscribeFn(LiftByOperatorObservable.scala:30)
  at monix.reactive.observables.ChainedObservable$.$anonfun$subscribe$1(ChainedObservable.scala:74)
  at monix.execution.internal.Trampoline.monix$execution$internal$Trampoline$$immediateLoop(Trampoline.scala:66)
  at monix.execution.internal.Trampoline.startLoop(Trampoline.scala:32)
  at monix.execution.schedulers.TrampolineExecutionContext$JVMOptimalTrampoline.startLoop(TrampolineExecutionContext.scala:132)
  at monix.execution.internal.Trampoline.execute(Trampoline.scala:40)
  at monix.execution.schedulers.TrampolineExecutionContext.execute(TrampolineExecutionContext.scala:57)
  at monix.execution.schedulers.BatchingScheduler.execute(BatchingScheduler.scala:50)
  at monix.execution.schedulers.BatchingScheduler.execute$(BatchingScheduler.scala:47)
  at monix.execution.schedulers.AsyncScheduler.execute(AsyncScheduler.scala:31)
  at monix.execution.schedulers.ExecuteExtensions.executeTrampolined(ExecuteExtensions.scala:86)
  at monix.execution.schedulers.ExecuteExtensions.executeTrampolined$(ExecuteExtensions.scala:85)
  at monix.execution.Scheduler$Extensions.executeTrampolined(Scheduler.scala:305)
  at monix.reactive.observables.ChainedObservable$.subscribe(ChainedObservable.scala:69)
  at monix.reactive.internal.operators.ConcatObservable.unsafeSubscribeFn(ConcatObservable.scala:37)
  at monix.reactive.observables.ChainedObservable.unsafeSubscribeFn(ChainedObservable.scala:55)
  at monix.reactive.internal.operators.OnErrorRecoverWithObservable$$anon$1.$anonfun$onError$1(OnErrorRecoverWithObservable.scala:57)
  at monix.execution.Ack$$anon$1.run(Ack.scala:54)
  at java.util.concurrent.ForkJoinTask$RunnableExecuteAction.exec(ForkJoinTask.java:1402)
  at java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:289)
  at java.util.concurrent.ForkJoinPool$WorkQueue.runTask(ForkJoinPool.java:1056)
  at java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:1692)
  at java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:172)
Caused by: io.netty.channel.ChannelException: failed to open a new selector
  at io.netty.channel.nio.NioEventLoop.openSelector(NioEventLoop.java:175)
  at io.netty.channel.nio.NioEventLoop.<init>(NioEventLoop.java:142)
  at io.netty.channel.nio.NioEventLoopGroup.newChild(NioEventLoopGroup.java:146)
  at io.netty.channel.nio.NioEventLoopGroup.newChild(NioEventLoopGroup.java:37)
  at io.netty.util.concurrent.MultithreadEventExecutorGroup.<init>(MultithreadEventExecutorGroup.java:84)
  ... 42 more
Caused by: java.io.IOException: Too many open files
  at sun.nio.ch.IOUtil.makePipe(Native Method)
  at sun.nio.ch.KQueueSelectorImpl.<init>(KQueueSelectorImpl.java:84)
  at sun.nio.ch.KQueueSelectorProvider.openSelector(KQueueSelectorProvider.java:42)
  at io.netty.channel.nio.NioEventLoop.openSelector(NioEventLoop.java:173)
  ... 46 more
any advice / direction is appreciated
Wojtek Pituła
hey, Im runnign sttp 1.x alongside sttp 2.x, both with prometheus backend and the clash with Collector already registered that provides name: sttp_request_latency_count. I know I can override those names, but maybe there is some other way?
1 reply
Glen Marchesani
So for my issue I added this (a memoize on the backend task which makes sense (I only need one backend AFAICT) --
val instance: Task[sttp.client.SttpBackend[Task, monix.reactive.Observable[java.nio.ByteBuffer], WebSocketHandler]] =
1 reply
Glen Marchesani
yeah that fixed it for me
Glen Marchesani
anyone recommend code for taking a
    val webSocketT: Task[WebSocket[Task]] = ...
12 replies
and getting a
      lazy val frames: Observable[WebSocketFrame.Incoming] =
using monix
here is what I have

      lazy val frames: Observable[WebSocketFrame.Incoming] = {
        Observable.unsafeCreate[WebSocketFrame.Incoming] { subscriber =>

          val cancelable = AssignableCancelable.multi()

          def feedOnNext(): Unit = {
            val receiveT: Task[(Either[WebSocketEvent.Close, WebSocketFrame.Incoming], WebSocket[Task])] =
                .flatMap { webSocket =>
                    .map(_ -> webSocket)
            cancelable :=
                .runAsync {
                  case Left(error) =>
                  case Right((Left(close), _)) =>
                    if ( logger.isTraceEnabled )
                      logger.trace(s"received close ${close}")
                  case Right((Right(frame), webSocket)) =>
                      .syncOnStopOrFailure {
                        case Some(th) =>
                          logger.error(s"error processing ${frame}", th)
                        case None =>
                          if ( logger.isTraceEnabled)
                            logger.trace(s"stop received closing WebSocket")

Glen Marchesani
any comments are appreciated
Glen Marchesani
okay here is something that doesn't do "unsafe" things
      lazy val frames: Observable[WebSocketFrame.Incoming] = {
        val receiveT: Task[(Either[WebSocketEvent.Close, WebSocketFrame.Incoming], WebSocket[Task])] =
            .flatMap { webSocket =>
                .map(_ -> webSocket)

        val receiveForObservableT: Task[(Either[WebSocketEvent.Close, WebSocketFrame.Incoming], Unit)] = receiveT.map(t => (t._1, ()))

        val observable: Observable[Either[WebSocketEvent.Close, WebSocketFrame.Incoming]] = Observable.fromAsyncStateAction[Unit,Either[WebSocketEvent.Close, WebSocketFrame.Incoming]](_ => receiveForObservableT)(())

          .collect {
            case Right(f) =>
6 replies
Mark Hammons
Hi, I'm having some weird behavior from sttp3 in some cases
when making a POST to (which is supposed to be an invalid ipv4 address), I get a ReadException while I expected sttp to give me a ConnectException.