kotlinlang #ktor

It's not well documented at all, but you do need to have curl installed ( how depends on the platform.). Some instructions are here: https://github.com/JetBrains/kotlin-native/tree/master/samples/libcurl

Nikky

02/25/2020, 8:23 AM

https://ktor.io/servers/features/locations.html#parameters-get here it mentions that additional parameters are retrieved from get or post parameters.. i guess that means that i can use forms with post action? is there any specific encoding type i have to use for this ? i tried this and it always says that the post request is unhandled

Nikky

02/25/2020, 8:56 AM

is there any utilities for receiving a post body (FormEncode.multipartFormData from a form) into a data class or something @Serializable other than

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call.receiveMultipart()

and manually receiving all parameters ?

waltermcq

02/25/2020, 9:12 PM

Hello, noob question for ktor and json via GSON (edit: solved)

Niro

02/26/2020, 3:00 PM

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private val client by lazy {
        HttpClient(engine) {
            install(JsonFeature) {
                serializer = KotlinxSerializer(Json.nonstrict).apply {
                    setMapper(Todo::class, Todo.serializer())
                }
            }
            install(WebSockets)
        }
    }

    suspend fun fetchNotes(): List<Todo> {
        val jsonString2 = client.get<String> {
            url("$baseUrl/todos")
            
        }
        return Json.nonstrict.parse(multiNoteSerializer, jsonString2)
    }

Jeff

02/27/2020, 12:03 PM

Hi guys whenever I update Ktor to version 1.3.1 from 1.1.2 in multiplatform it can no longer resolve KotlinxSerializer() What am I doing wrong?

Saood

02/27/2020, 4:21 PM

Did anyone tried configureSession() with ktor to set delegate for certificate validation? ktor version 1.3

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Ios.create {
    configureSession {
    }
}

Delegate method for certificate validation

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func urlSession(_ session: URLSession, didReceive challenge: URLAuthenticationChallenge, completionHandler: @escaping (URLSession.AuthChallengeDisposition, URLCredential?) -> Swift.Void)

Narek Mailian

02/28/2020, 11:29 AM

Hi! I'm trying to serialize a list of polymorphic objects, but get the error "Serializing collections of different element types is not yet supported". Is there any workaround one can use? (besides wrapping everything in a serializable data class with a list)

Jan Stoltman

02/28/2020, 12:55 PM

Hey, is there any way to catch exceptions thrown by Ios client engine when there is no internet connection? So far I cannot wrap my head around how swift errors are propagated into kotlin

codec

02/28/2020, 7:41 PM

log()

function… because it’s not in the

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org.jetbrains.kotlinx:kotlinx-coroutines-core:1.3.3

library…

Muh Rahmatullah

02/29/2020, 6:47 PM

Hi all, new to ktor, I am creating simple api using ktor and gson for json serialization. I tried to handle simple POST request which has json payload but I always got error when I wanted to retrieve the payload using

call.receive<Foo>()

and the error is

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java.lang.UnsupportedOperationException: This function has a reified type parameter and thus can only be inlined at compilation time, not called directly.

this is the post handler:

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fun Route.createMovie(movies: MutableList<Movie>) {
    post("/movie") {
        val id = Random.nextInt(1, 100000)
        println("header ${call.request.headers["Content-Type"]}")
        if(movies.find { it.id == id.toString() } != null) {
            // this is example to modify status code in the response and assign the value to the response wrapper
            call.response.status(value = HttpStatusCode.BadRequest)
            call.respond(Response(data = null, code = call.response.status()?.value, message = "Movie with $id already exist"))
        } else {
            val payload = call.receive<Movie>()
            println(payload)
            movies.add(payload)
            call.respond(Response(data = movies, code = 200, message = "OK"))
        }
    }
}

and my Application

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fun Application.module(testing: Boolean = false) {

    val movies = initData()

    install(ContentNegotiation) {
        gson {
            setPrettyPrinting()
        }
    }

    routing {
        get("/") {
            call.respondText("A very simple rest api using k-tor!", contentType = ContentType.Text.Plain)
        }
        movies(movies)
        movieById(movies)
        deleteById(movies)
        createMovie(movies)
    }
}

Also, I already set the Content-type to application/json when sending the request. TIA, any help would be great

ribesg

03/01/2020, 12:42 PM

When using the Ktor Client in JS, getting an URL like

/example

gets

<http://localhost/example>

. Is it intended?

🚫 1

sultanofcardio

03/02/2020, 7:16 PM

Hi everyone. I'm interested in generating swagger docs and serving swagger UI from ktor. The serving part is pretty easy with static files but there seems to be no official way to generate swagger docs from ktor routes. There is also this (https://github.com/ktorio/ktor/issues/453) unofficial solution which hasn't gotten any attention from JB since its reporting in 2018. Can anyone say if this is a feature JB is looking at?

Shan

03/02/2020, 11:00 PM

Hey all. I have my

AndroidEngineConfig

set up in a way that if the method isn't

GET

HEAD

DELETE

to set the content type to

ContentType.Application.Json

. This is fine for all of my

POST

requests with bodies, but I now need to make a

POST

request without a body (it is only a path with an Empty response), and I am getting:

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io.ktor.http.UnsafeHeaderException: Header Content-Type is controlled by the engine and cannot be set explicitly

Is there any way I can override the

Content-Type

for this single request, or is there a way I can programmatically set it for each individual request?

Henrik

03/03/2020, 11:07 AM

Hello all. I am using ktor in Android+iOS, but I have a problem with ktor not downloading the entire file always. When downloading to ByteArray, the array does not contain all the bytes of the file. Any ideas why? Is this call not blocking, so I read it prematurely or similar? Using ktor 1.3.1 and Kotlin 1.3.61

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private val client = HttpClient()
val result: ByteArray = client.get {
                        url(url.toString())
                    }

sultanofcardio

03/03/2020, 5:48 PM

I think version

1.3.70-release-IJ2019.3-1

of the Kotlin plugin in IntelliJ has broken ktor builds. The source of this stack trace is the declaration of the

Application.module

extension function

stacktrace.txt

ribesg

03/04/2020, 9:45 AM

If anyone has an idea on how I could help fix this issue https://github.com/ktorio/ktor/issues/1650 I already spent some hours trying to create a reproducer with no luck

❗ 1

tylerwilson

03/04/2020, 6:12 PM

Do we need an updated ktor to work with kotlin 1.3.70 and serialization 0.20.? I am getting the following error at run time:

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java.lang.NoSuchFieldError: No field Companion of type Lkotlinx/serialization/json/Json$Companion; in class Lkotlinx/serialization/json/Json; or its superclasses (declaration of 'kotlinx.serialization.json.Json' appears in /data/app/com.webappclouds.salonbiz-ZLc1BlPrwYueYBzBSLTUTg==/base.apk!classes3.dex)

👌 1

John Peña

03/04/2020, 9:51 PM

is there a way to make a

TestApplicationCall

without going through all the tediousness of making a test server, test engine, test request, etc

napperley

03/04/2020, 10:55 PM

Appears as though Ktor Client hasn't caught up to support Kotlin 1.3.70 yet. Waiting for a newer version of the io.ktor:ktor-client-curl artifact with support for the linuxX64 target.

napperley

03/05/2020, 1:35 AM

Is there a early access version of Ktor Client available that supports Kotlin 1.3.70?

napperley

03/05/2020, 1:41 AM

Is this version of Ktor Client ( https://mvnrepository.com/artifact/io.ktor/ktor-client/1.3.0-rc3-1.3.70-eap-42 ) related to Kotlin 1.3.70?

rrva

03/05/2020, 10:36 AM

Using ktor client, how do I handle a JSON response of type List<Foo> ? I get kotlinx.serialization.SerializationException: Can't locate argument-less serializer for class kotlin.collections.List. For generic classes, such as lists, please provide serializer explicitly. How do I provide a specific list serializer? I am on ktor 1.2.x but can upgrade to 1.3.1

gabin

03/05/2020, 2:42 PM

Hi guys, I’m using ktor+kotlinx.serialization. When I’m trying to get typed response I get a runtime crash:

Exception in thread "main" java.lang.NoClassDefFoundError: kotlinx/serialization/ShorthandsKt

at io.ktor.client.features.json.serializer.KotlinxSerializerKt.buildSerializer(KotlinxSerializer.kt:91)

at io.ktor.client.features.json.serializer.KotlinxSerializerKt.access$buildSerializer(KotlinxSerializer.kt:1)

at io.ktor.client.features.json.serializer.KotlinxSerializer.write(KotlinxSerializer.kt:69)

at io.ktor.client.features.json.JsonFeature$Feature$install$1.invokeSuspend(JsonFeature.kt:101)

at io.ktor.client.features.json.JsonFeature$Feature$install$1.invoke(JsonFeature.kt)

at io.ktor.util.pipeline.SuspendFunctionGun.loop(PipelineContext.kt:273)

Can you point me what’s wrong? ktor 1.3.1, serialization 0.20.0

gabin

03/05/2020, 4:56 PM

I’ve installed logging feature, but it seems not working

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install(Logging) {
    logger = Logger.ANDROID
    level = LogLevel.ALL
}

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implementation "io.ktor:ktor-client-logging-jvm:$ktorVersion"

in logs I only see exception:

2020-03-05 16:16:33.829 1383-1383/? W/System.err: SLF4J: Failed to load class "org.slf4j.impl.StaticLoggerBinder".

2020-03-05 16:16:33.829 1383-1383/? W/System.err: SLF4J: Defaulting to no-operation (NOP) logger implementation

2020-03-05 16:16:33.829 1383-1383/? W/System.err: SLF4J: See <http://www.slf4j.org/codes.html#StaticLoggerBinder> for further details.

is there a way to make it work ?

christophsturm

03/06/2020, 10:56 AM

does ktor have an oauth2 client?

CLOVIS

03/06/2020, 11:21 AM

Hi! I'm new at Ktor and kotlinx.serialization so this may be a very dumb question, sorry if that's the case... I'm trying to setup a multiplatform client to access some REST API. My example is an endpoint (

/account/auth/

) which I should send a JSON object to, which contains a field

username

and a field

password

. It should return a JSON object that contains a

token

field. I want to use Kotlinx.Serialization to generate the JSON objects, so I started with:

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@Serializable
private data class ApiUsernamePassword(val username: String, val password: String)

and I do my request like this:

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val client = HttpClient() {
    install(JsonFeature) {
        serializer = KotlinxSerializer()
    }
}

val res = <http://client.post|client.post><String> {
    url("<http://localhost:8000/account/auth/>")

    body = ApiUsernamePassword(username, password)
}

On the JVM, I get this error:

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Companion
java.lang.NoSuchFieldError: Companion
	at io.ktor.client.features.json.serializer.KotlinxSerializer.<init>(KotlinxSerializer.kt:22)

(I can send the full stacktrace if needed) On JS, I get this error:

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TypeError: Cannot read property 'plain' of undefined

    at new KotlinxSerializer (<http://localhost:9876/absolute/[REDACTED]/adapter-browser.js?fb6a5f1e12e8cc2bf794189b2b55f22def38ca94:157371:29>)

I've tried Googling it but I don't get any meaningul/related results for both of those errors... Did anyone encounter this before? I also tried adding an empty companion object to my serializable class but it didn't change anything. (all of the above is in the common module, if that's relevant)

gabin

03/06/2020, 12:02 PM

hey guys, is there some mechanism that allows to make refresh token request if I got a special error and repeat the initial request after that ?

tim

03/07/2020, 3:42 PM

Hi folks, i'm struggling to figure out how to test a ktor client making a post request. I have a class called MailSender which posts to a remote server. In MailSenderTest I would like to catch the underlying post request inspect it ... but I can't seem to figure out how to do this. I was looking into the MockEngine, but to get that to work MailSender needs to have access to the MockEngine which is in my testImplementation dependencies ... this should be straightforward so i'm clearly missing something ... any suggestions?

jpg

03/08/2020, 10:41 AM

If you are not tied to Apache Kafka I would consider using something different for this usecase. Depending on your requirements an AMQP based system could work or Apache Pulsar which has better messaging like semantics that are more suited to this workload than Kafkas streaming worldview.