Is there a reason

io.ktor.client.plugins.auth.providers.AuthTokenHolder

is declared internal? I would like to utilize it in custom client

AuthProvider

fun isTokenBlacklistedAdmin(token: Payload): Boolean {
    val fetch =  transaction {
        AdminTokenTable.select {
            AdminTokenTable.token eq token.toString()
        }.firstOrNull()?.let {
            AdminTokenList(
                token = it[AdminTokenTable.token],
                blackList = it[AdminTokenTable.blackList]
            )
        }
    }
    return when (
       fetch?.blackList
    ) {
        1 -> {

            true
        }

        0 -> {
            println("0")
            false
        }

        else -> {
            true
        }
    }
}

I have such a code block. While performing JWT validation, I want to check from the database whether the token is blacklisted. But how can I read the token from Payload? token.toString() doesn't work. I couldn't find any detailed information.

I'm using ktor client with the CIO engine for my kt-search client (a rest client for opensearch and elasticsearch). We recently switched to this with our main application (Spring Boot) and now running our multi threaded tests (we run with ten or so junit threads), I get a few weird exceptions that randomly fail small portion of the tests (see stacktrace below) After a bit of digging, I narrowed the problem down to the CIO engine and I suspect it's not completely threadsafe somehow. Switching to the Java engine makes the problem go away completely. I haven't tried any of the other engines. The previous version of the client would have used Elastic's RestHighLevel client, which in turn uses Apache http client if I recall correctly. So the main change here is that we are now using a different Rest client. Looking at the documentation, I wonder if there is any guidance on pros/cons of each engine. There seem to be a lot of them at least. For reference, this is the stack trace. It looks to me like different threads are ending up trying to open the same port somehow or messing with the same connection.

java.net.BindException: Can't assign requested address
	at java.base/sun.nio.ch.Net.connect0(Native Method)
	at java.base/sun.nio.ch.Net.connect(Net.java:579)
	at java.base/sun.nio.ch.Net.connect(Net.java:586)
	at java.base/sun.nio.ch.SocketChannelImpl.connect(SocketChannelImpl.java:853)
	at io.ktor.network.sockets.SocketImpl.connect$ktor_network(SocketImpl.kt:44)
	at io.ktor.network.sockets.ConnectUtilsJvmKt.connect(ConnectUtilsJvm.kt:21)
	at io.ktor.network.sockets.TcpSocketBuilder.connect(TcpSocketBuilder.kt:37)
	at io.ktor.client.engine.cio.ConnectionFactory.connect(ConnectionFactory.kt:29)
	at io.ktor.client.engine.cio.Endpoint$connect$2$connect$1.invokeSuspend(Endpoint.kt:156)
	at io.ktor.client.engine.cio.Endpoint$connect$2$connect$1.invoke(Endpoint.kt)
	at io.ktor.client.engine.cio.Endpoint$connect$2$connect$1.invoke(Endpoint.kt)
	at kotlinx.coroutines.intrinsics.UndispatchedKt.startUndispatchedOrReturnIgnoreTimeout(Undispatched.kt:100)
	at kotlinx.coroutines.TimeoutKt.setupTimeout(Timeout.kt:146)
	at kotlinx.coroutines.TimeoutKt.withTimeoutOrNull(Timeout.kt:103)
	at io.ktor.client.engine.cio.Endpoint.connect(Endpoint.kt:164)
	at io.ktor.client.engine.cio.Endpoint.makeDedicatedRequest(Endpoint.kt:98)
	at io.ktor.client.engine.cio.Endpoint.execute(Endpoint.kt:62)
	at io.ktor.client.engine.cio.CIOEngine.execute(CIOEngine.kt:84)
	at io.ktor.client.engine.HttpClientEngine$executeWithinCallContext$2.invokeSuspend(HttpClientEngine.kt:99)
	at ???(Coroutine boundary.?(?)
	at io.ktor.client.engine.HttpClientEngine$DefaultImpls.executeWithinCallContext(HttpClientEngine.kt:100)
	at io.ktor.client.engine.HttpClientEngine$install$1.invokeSuspend(HttpClientEngine.kt:70)
	at io.ktor.client.plugins.HttpSend$DefaultSender.execute(HttpSend.kt:138)
	at io.ktor.client.plugins.HttpRedirect$Plugin$install$1.invokeSuspend(HttpRedirect.kt:61)
	at io.ktor.client.plugins.HttpCallValidator$Companion$install$3.invokeSuspend(HttpCallValidator.kt:147)
	at io.ktor.client.plugins.HttpSend$Plugin$install$1.invokeSuspend(HttpSend.kt:104)
	at io.ktor.client.plugins.DefaultTransformKt$defaultTransformers$1.invokeSuspend(DefaultTransform.kt:53)
	at io.ktor.client.plugins.HttpCallValidator$Companion$install$1.invokeSuspend(HttpCallValidator.kt:126)
	at io.ktor.client.plugins.HttpRequestLifecycle$Plugin$install$1.invokeSuspend(HttpRequestLifecycle.kt:35)
	at io.ktor.client.HttpClient.execute$ktor_client_core(HttpClient.kt:191)
	at io.ktor.client.statement.HttpStatement.executeUnsafe(HttpStatement.kt:108)
	at io.ktor.client.statement.HttpStatement.execute(HttpStatement.kt:47)
	at com.tryformation.api.graphql.FormationClient.executeRaw(FormationClient.kt:1037)
	at com.tryformation.api.graphql.FormationClient.execute(FormationClient.kt:919)
	at com.tryformation.graphqlapi.TestTeamAndClientCreator.createTeam$suspendImpl(APITest.kt:211)
	at com.tryformation.graphqlapi.analytics.ArmyTestFixture.create(ArmyTestFixture.kt:272)
	at com.tryformation.graphqlapi.analytics.ArmyTestFixture$armyWorkspace$2$1.invokeSuspend(ArmyTestFixture.kt:269)
	at com.tryformation.graphqlapi.TestbeansKt$runTest$1.invokeSuspend(testbeans.kt:257)
Caused by: java.net.BindException: Can't assign requested address
	at java.base/sun.nio.ch.Net.connect0(Native Method)
	at java.base/sun.nio.ch.Net.connect(Net.java:579)
	at java.base/sun.nio.ch.Net.connect(Net.java:586)
	at java.base/sun.nio.ch.SocketChannelImpl.connect(SocketChannelImpl.java:853)
	at io.ktor.network.sockets.SocketImpl.connect$ktor_network(SocketImpl.kt:44)
	at io.ktor.network.sockets.ConnectUtilsJvmKt.connect(ConnectUtilsJvm.kt:21)
	at io.ktor.network.sockets.TcpSocketBuilder.connect(TcpSocketBuilder.kt:37)
	at io.ktor.client.engine.cio.ConnectionFactory.connect(ConnectionFactory.kt:29)
	at io.ktor.client.engine.cio.Endpoint$connect$2$connect$1.invokeSuspend(Endpoint.kt:156)
	at io.ktor.client.engine.cio.Endpoint$connect$2$connect$1.invoke(Endpoint.kt)
	at io.ktor.client.engine.cio.Endpoint$connect$2$connect$1.invoke(Endpoint.kt)
	at kotlinx.coroutines.intrinsics.UndispatchedKt.startUndispatchedOrReturnIgnoreTimeout(Undispatched.kt:100)
	at kotlinx.coroutines.TimeoutKt.setupTimeout(Timeout.kt:146)
	at kotlinx.coroutines.TimeoutKt.withTimeoutOrNull(Timeout.kt:103)
	at io.ktor.client.engine.cio.Endpoint.connect(Endpoint.kt:164)
	at io.ktor.client.engine.cio.Endpoint.makeDedicatedRequest(Endpoint.kt:98)
	at io.ktor.client.engine.cio.Endpoint.execute(Endpoint.kt:62)
	at io.ktor.client.engine.cio.CIOEngine.execute(CIOEngine.kt:84)
	at io.ktor.client.engine.HttpClientEngine$executeWithinCallContext$2.invokeSuspend(HttpClientEngine.kt:99)
	at kotlin.coroutines.jvm.internal.BaseContinuationImpl.resumeWith(ContinuationImpl.kt:33)
	at kotlinx.coroutines.DispatchedTask.run(DispatchedTask.kt:106)
	at kotlinx.coroutines.internal.LimitedDispatcher.run(LimitedDispatcher.kt:42)
	at kotlinx.coroutines.scheduling.TaskImpl.run(Tasks.kt:95)
	at kotlinx.coroutines.scheduling.CoroutineScheduler.runSafely(CoroutineScheduler.kt:570)
	at kotlinx.coroutines.scheduling.CoroutineScheduler$Worker.executeTask(CoroutineScheduler.kt:750)
	at kotlinx.coroutines.scheduling.CoroutineScheduler$Worker.runWorker(CoroutineScheduler.kt:677)
	at kotlinx.coroutines.scheduling.CoroutineScheduler$Worker.run(CoroutineScheduler.kt:664)

Hei Ktor team. • We have seen this issue since 1.6.x, and have been bitten by it pretty much every other day in production. • This issue only occurs on apis where response header has transfer-enconding=chunked and without content length specified. • As soon as this happens, it poisons the whole ktor client and only way it comes back to normal is by restarting our servers. • We have seen this issue being raised in youtrack and marked as solved, but we still see it. we are using 2.2.2 as current ktor client version, with CIO as http client engine. • We have tried removing different http client plugins to eliminate points of failure, but it keeps happening. • We have also tried using Apache engine in the ktor HttpClient, it still happens. Problem is, we have never been successful in reproducing this issue locally. Can you look at the stack trace and give us some clue, eventually, identify if something needs to be done in the ktor client libraries ?

java.io.EOFException: Invalid chunk: content block of size <8192| multiple of 8> ended unexpectedly
	at io.ktor.http.cio.ChunkedTransferEncodingKt.decodeChunked(ChunkedTransferEncoding.kt:93)
	at io.ktor.http.cio.ChunkedTransferEncodingKt$decodeChunked$3.invokeSuspend(ChunkedTransferEncoding.kt)
	at kotlin.coroutines.jvm.internal.BaseContinuationImpl.resumeWith(ContinuationImpl.kt:33)
	at kotlinx.coroutines.DispatchedTask.run(DispatchedTask.kt:106)
	at kotlinx.coroutines.internal.LimitedDispatcher.run(LimitedDispatcher.kt:42)
	at kotlinx.coroutines.scheduling.TaskImpl.run(Tasks.kt:95)
	at kotlinx.coroutines.scheduling.CoroutineScheduler.runSafely(CoroutineScheduler.kt:570)
	at kotlinx.coroutines.scheduling.CoroutineScheduler$Worker.executeTask(CoroutineScheduler.kt:750)
	at kotlinx.coroutines.scheduling.CoroutineScheduler$Worker.runWorker(CoroutineScheduler.kt:677)
	at kotlinx.coroutines.scheduling.CoroutineScheduler$Worker.run(CoroutineScheduler.kt:664)
	Suppressed: java.io.EOFException: Invalid chunk: content block of size 8192 ended unexpectedly
		at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
		at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:77)
		at java.base/jdk.internal.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
		at java.base/java.lang.reflect.Constructor.newInstanceWithCaller(Constructor.java:499)
		at java.base/java.lang.reflect.Constructor.newInstance(Constructor.java:480)
		at io.ktor.utils.io.ExceptionUtilsJvmKt$createConstructor$$inlined$safeCtor$3.invoke(ExceptionUtilsJvm.kt:103)
		at io.ktor.utils.io.ExceptionUtilsJvmKt$createConstructor$$inlined$safeCtor$3.invoke(ExceptionUtilsJvm.kt:90)
		at io.ktor.utils.io.ExceptionUtilsJvmKt.tryCopyException(ExceptionUtilsJvm.kt:66)
		at io.ktor.utils.io.ByteBufferChannelKt.rethrowClosed(ByteBufferChannel.kt:2400)
		at io.ktor.utils.io.ByteBufferChannelKt.access$rethrowClosed(ByteBufferChannel.kt:1)
		at io.ktor.utils.io.ByteBufferChannel.setupStateForRead(ByteBufferChannel.kt:295)
		at io.ktor.utils.io.ByteBufferChannel.copyDirect$ktor_io(ByteBufferChannel.kt:3377)
		at io.ktor.utils.io.ByteBufferChannel$copyDirect$1.invokeSuspend(ByteBufferChannel.kt)
		... 8 more
	Caused by: [CIRCULAR REFERENCE: java.io.EOFException: Invalid chunk: content block of size 8192 ended unexpectedly]

Another stacktrace I see on the same issue

java.io.EOFException: Invalid chunk: content block of size 8192 ended unexpectedly
	at io.ktor.http.cio.ChunkedTransferEncodingKt.decodeChunked(ChunkedTransferEncoding.kt:93)
	at io.ktor.http.cio.ChunkedTransferEncodingKt$decodeChunked$3.invokeSuspend(ChunkedTransferEncoding.kt)
	at kotlin.coroutines.jvm.internal.BaseContinuationImpl.resumeWith(ContinuationImpl.kt:33)
	at kotlinx.coroutines.DispatchedTask.run(DispatchedTask.kt:106)
	at kotlinx.coroutines.internal.LimitedDispatcher.run(LimitedDispatcher.kt:42)
	at kotlinx.coroutines.scheduling.TaskImpl.run(Tasks.kt:95)
	at kotlinx.coroutines.scheduling.CoroutineScheduler.runSafely(CoroutineScheduler.kt:570)
	at kotlinx.coroutines.scheduling.CoroutineScheduler$Worker.executeTask(CoroutineScheduler.kt:750)
	at kotlinx.coroutines.scheduling.CoroutineScheduler$Worker.runWorker(CoroutineScheduler.kt:677)
	at kotlinx.coroutines.scheduling.CoroutineScheduler$Worker.run(CoroutineScheduler.kt:664)

Is there a ktor-client plugin that adds set of default headers such as Date (counterpart to server plugin DefaultHeaders)?

I’m trying to set up a Ktor server. When I copy and paste the example for configuration in code, IntelliJ gives a warning that I don’t really understand.

EmbeddedServer should reference top level Application module extension

IntelliJ provides a quick-fix, but this prevents me from passing in any arguments to the configuration function. I want to configure the Ktor server using main args 🧵, but I can’t see how to do that without this warning. Any ideas?

Hello. My kotlin multiplatform project is based on https://kotlinlang.org/docs/multiplatform-full-stack-app.html The application works in production mode, but throws the following JavaScript error on page load when I switch to development mode. It happens while trying to fetch data via REST via React's

useEffectOnce {
    scope.launch {
        ...
    }
}

ReferenceError: Job is not defined at HttpClient (webpack-internal:///./kotlin/ktor-ktor-client-core-js-ir.js:599:24)

Dependency versions:

val kotlinVersion = "1.8.0"
val kotlinxCoroutinesVersion = "1.6.4"
val serializationVersion = "1.3.3"
val ktorVersion = "2.0.3"
val logbackVersion = "1.2.11"
val kotlinWrappersVersion = "1.0.0-pre.354"

using js(IR) compiler Thanks for your help in advance!

There should be an error somewhere when calling

<http://io.ktor.server.routing.post|io.ktor.server.routing.post>

if the reified type used is marked with

@Resource

. Just had everything fail with 404 errors because I didn't manually import

<http://io.ktor.server.resources.post|io.ktor.server.resources.post>

and my IDE saw nothing wrong with that.

Hey I'm using the

RequestValidation

plugin and I was curious if there was any way to either extend

ValidationResult.Invalid

to include a Throwable, or a way to pass a throwable to

StatusPages

using

ValidationResult

. Currently I am just throwing an error in the

install(RequestValidation) {}

block and always returning

ValidationResult.Valid

but that feels like a gross workaround

Hello guys, what is the best way to send one time data between request? Like a flash session? After a post request, i want to redirect to another page and to display a success/error message, what is the best way in ktor to redirect to another page and to pass data to it.

Hi, Also posted to #serialization but it's also related to ktor: Can anyone help me with this?

What dispatcher does ktor client make requests on? Does it depend on engine? I’m seeing

DarwinClientEngine

declares

Unconfined

dispatcher, but not sure this it’s actually being used for requests?

I've got a strange issue that I can't seem to resolve. I have some data classes that look as follows:

@Serializable
data class Tag(
    val name: String,
    @Serializable(with = TagStringSerializer::class)
    val parent: Tag? = null,
    val subTags: MutableSet<@Serializable(with = TagStringSerializer::class) Tag> = ConcurrentSet(),
    val files: MutableSet<@Serializable(with = SavedFileStringSerializer::class) SavedFile> = ConcurrentSet()
)

@Serializable
data class SavedFile(
    @Serializable(with = FileSerializer::class)
    val file: File,
    val tags: MutableSet<@Serializable(with = TagStringSerializer::class) Tag> = ConcurrentSet()
)

Of course, I don't want recursive Tags/SavedFiles in my serialization, as that would lead to infinite loops; I only serialize the names (all my custom serializers do is extract names). When I use

ApplicationCall#respond(savedFile)

, this works properly and sends

{"file":"example","tags":["test"]}

. However, when I do

ApplicationCall#respond(savedFile.tags)

, I receive an array of default-serialized tags instead of just the names, as if it's ignoring the annotation in the set:

[{"name":"test","subTags":[],"files":["example"]}]

. Even stranger, when I do just

Json.encodeToString(savedFile.tags)

, it works just fine and gives me a properly-encoded array

["test"]

. Of course, I could just create a function like

respondJson

and wrap a call to

respondText(Json.encodeToString(

, but this seems hacky and non-ideal. I'm just very confused as to why the two functions are behaving differently and how I can fix the serialization done within

ApplicationCall#respond

.

What is the preferred way of validating query, path and headers? Wrapping everything in try/catches is not really DRY in my opinion. For instance, I'd have a UUID as a path parameter. I use UUID.fromString which might fail. I can wrap that with a try/catch and send a response. What is the idiomatic thing of repeatedly handling validation of these parameters?

hi, i am currently testing kmm and i am building a small app with a simple api request generated with openapi generator. the get request was pretty straight forward now i am trying to implement a post request and i always get the error "java.lang.IllegalStateException: Fail to prepare request body for sending. " despite the correct declaration in the openapi file. does anybody know if i need to change the openapi file in order to work properly with ktor or if there is a special setting i need for the generation? Openapi file is in the thread

Hi! I'm a total ktor noob. I helped someone connect OPENRNDR with websockets, but it works only on localhost: https://openrndr.discourse.group/t/using-openrndr-as-a-websocket-client/532/9?u=abe I don't see examples in the ktor website for connecting to WSS servers. Any pointers as to what I should change in that code to connect to an online service? Thanks!

Can anyone tell me what's wrong here? What am I doing wrong.

@Test
    fun test() = testApplication {
        externalServices {
            hosts("<wss://test.com>") {
                install(io.ktor.server.websocket.WebSockets) { }

                routing {
                    webSocket("/test") {
                        send(Frame.Text("hello"))
                    }
                }
            }
        }

        val client = createClient {
            install(WebSockets) {
                contentConverter = KotlinxWebsocketSerializationConverter(
                    Json {
                        ignoreUnknownKeys = true
                    }
                )
            }
        }

        runBlocking {
            client.wss(host = "<http://test.com|test.com>", path = "test") {
                val string = Json.encodeToString(User("foo"))
//                     val string = """{"name":"foo"}"""
                println(string)
                send(Frame.Text(string))
            }
        }
    }

On the runBlocking block; both lines prints

{"name":"foo"}

but the`send` function throws

java.util.concurrent.CancellationException: ArrayChannel was cancelled

error for the first

string

, and it doesn't throw for the second.

Regarding ktor-client, is there a tool for creating record/replay tests?

Which free hosting website should I use to deploy my Ktor apps?

Is anyone here working on both mobile and backend professionally? Can anyone be defined as a full stack mobile dev or full stack kotlin dev? Did you have to convince your company for that career path or was it already established?

I'm using a library designed around coroutines that also uses ktor so I also have ktor goodies to use. I noticed ktor provides "channels" (

ByteReadChannel

,

ByteWriteChannel

, what's the benefit of them? And what does the following mean?

Operations on this channel cannot be invoked concurrently.

when is a

ByteWriteChannel

more convenient than this?

val url = URL(...)
val targetDir = Path.of(...)

withContext(<http://Dispatchers.IO|Dispatchers.IO>) {
  url.openStream().use { stream ->
    Files.copy(stream, targetDir)
  }
}

are they just meant to be used to read and write in chunks without blocking everything else in a thread, and to yield it to other coroutines?

Hello there! I'm trying to send a UDP message using ktor and getting this exception

Exception in thread "main" java.net.BindException: Can't assign requested address
	at java.base/sun.nio.ch.DatagramChannelImpl.send0(Native Method)
	at java.base/sun.nio.ch.DatagramChannelImpl.sendFromNativeBuffer(DatagramChannelImpl.java:587)
	at java.base/sun.nio.ch.DatagramChannelImpl.send(DatagramChannelImpl.java:549)
	at java.base/sun.nio.ch.DatagramChannelImpl.send(DatagramChannelImpl.java:532)
	at io.ktor.network.sockets.DatagramSendChannel$send$2$1.invokeSuspend(DatagramSendChannel.kt:80)
	at kotlin.coroutines.jvm.internal.BaseContinuationImpl.resumeWith(ContinuationImpl.kt:33)
	at kotlinx.coroutines.DispatchedTask.run(DispatchedTask.kt:106)
	at kotlinx.coroutines.internal.LimitedDispatcher.run(LimitedDispatcher.kt:42)
	at kotlinx.coroutines.scheduling.TaskImpl.run(Tasks.kt:95)
	at kotlinx.coroutines.scheduling.CoroutineScheduler.runSafely(CoroutineScheduler.kt:570)
	at kotlinx.coroutines.scheduling.CoroutineScheduler$Worker.executeTask(CoroutineScheduler.kt:750)
	at kotlinx.coroutines.scheduling.CoroutineScheduler$Worker.runWorker(CoroutineScheduler.kt:677)
	at kotlinx.coroutines.scheduling.CoroutineScheduler$Worker.run(CoroutineScheduler.kt:664)

This is my code:

fun main() {
	runBlocking {
	    val selectorManager = SelectorManager(<http://Dispatchers.IO|Dispatchers.IO>)
        val socket = aSocket(selectorManager)
            .udp()
            .bind(InetSocketAddress("127.0.0.1", 4756))

        launch(<http://Dispatchers.IO|Dispatchers.IO>) {
            for (datagram in socket.incoming) {
                val bytes = datagram.packet.readBytes()
                val decoded = decode(bytes)
                <http://logger.info|logger.info>("Received: $decoded from ${datagram.address}")
            }
        }


        val packet = BytePacketBuilder().apply { request }.build() // Here I create the packet to send, just raw bytes, nothing related to the problem
        val message = Datagram(
            packet = packet,
            address = InetSocketAddress("<http://router.bittorrent.com|router.bittorrent.com>", 6881)
        )

        socket.send(message)
	}
}

No idea why this is happening, can any one help me please?

Regarding the request validation : https://ktor.io/docs/request-validation.html#validation-exception, how does it work when I’ll have a ton of routes, can I apply the validation to specific routes or even to a single route ? According to the doc, I should do :

install(RequestValidation) {
        validate<Post> { post ->
            if (post.title.length < 4)
                ValidationResult.Invalid("A post ID should be greater than 0")
            else ValidationResult.Valid
        }
        ...

But eventually there will be a lot of validations in there. It would be nice if I could apply to my post routes, only the validation regarding the posts…

Hi everyone. I’m using Ktor to make a localhost. I want it can be restarted so this is what I have done: • Create embeddedServer • Start it by function start(wait = true) • Stop it by function stop() • Create new instance of embeddedServer then start it again. I don’t know why whenever I restart the server it’s always throw exception: port already in use. Is the port does not released by Ktor or I was doing wrong?

Hi, I'm trying to write unit tests for a websocket client and I was looking at the tests on ktor. 🧵

Hi. Can I somehow create routes in Ktor that are only matched against certain client IP addresses or based on which server IP it came from? I would like to handle requests to localhost differently than others.

Is it possible to share type safe definition of the API defined using the Resources plugin between ktor client and server? (io.ktor:ktor-server-resources and io.ktor:ktor-client-resources)

Is there any workaround in dealing with nullable values in json when working with ktor client(Android)?

what's the difference between @resource and @location? they look so similar to me i've searched around but all i found was this dead forum link https://kotlinlang.slack.com/archives/C0X8H6XFA/p1677816564379959