Hi, I'm not too much into Ktor jet (even if I already created one or two projects with it), and just wanted to ask some general question about the idea behind Ktor: (let's ignore the client part for this question): Is Ktor a Framework for HTTP communication only or should it more seen as a generic way of building server applications? So should it also be possible (in the future) e.g. to build a server application listening on RabbitMQ completely independent of HTTP?

Hey, how can I install a feature if my main class is not of type io.ktor.application? I'm using Java 9.

is it just for me or does the example here not work: https://ktor.io/clients/http-client/testing.html

Hello! I have created a Ktor feature https://github.com/mjstrasser/ktor-features-zipkin/ that enables a Ktor app to participate in Zipkin distributed tracing. The code includes a server feature that recognises Zipkin HTTP tracing headers and a client feature that propagates headers into downstream calls. Let me know what you think, and whether it is useful to you.

I have read https://ktor.io/advanced/pipeline.html but I am still a bit lost when it comes to how to control exactly when a Feature is run. I have a feature that should be run after authentication (I want to check if a principal is present) but before it is too late to make a

call.respond(...)

. It seems that whenever I insert my feature to a

PipelinePhase

it is either too early for the principal to have been processed (I can see for example that the

Authorization

header is present, but

principal

is null because it has not been set yet) or to late to make a response to the request. How do I solve this (in a good manner)?

By default, Ktor HTTP client does follow redirections; this feature allows to follow Location redirects in a way that works with any HTTP engine.

vs

The iOS engine uses the asynchronous NSURLSession internally. And have no additional configuration.

What is right? I use

followRedirects=false

in MPP common code and on android it works properly but obviously it still follows redirects on iOS. Any way possible to force ktor not to follow redirects on iOS?

<http://httpClient.ws|httpClient.ws>(...)

does not propagate errors... is there any way to catch them?

Why can’t I set the content type on a request? It fails saying the engine should handle the content type header, what does that mean?

Found a small issue, this doesn’t work when using okhttp3 engine:

<http://http.post|http.post>(url) {
            body = EmptyContent
        }

How does one post an object via

HttpClient

that should be Json Encoded? Using iOS, if that matters, and I have the

JsonFeature

installed... but I get

kotlin.ClassCastException: example.model.Person cannot be cast to io.ktor.client.call.HttpClientCall

. Here's my code:

runBlocking {
            val client = HttpClient()

            val message = <http://client.post|client.post><Person> { //(path = "/path") {
                url("<http://localhost:8080/path>")
                contentType(ContentType.Application.Json)
                body = Person("James", "Smith")
            }
        }

...

Person

is

@Serializable

, should I not be setting it to the body of the post request like this? I assumed that, being

Any

,

JsonFeature

would know how to handle this? Can't find an example or details in ktor documentation.

and besides, with the settings like in the docs, you dont need that http client, you can use embeddedserver and that’s it, they dont even initialize that instance, the one that lights up red

Yes, do a safe cast

call as? RoutingApplicationCall

. If it’s not null, you’re in a route handler (or interceptor) and you can get route from there. However, you need to place interceptor inside

routing

for this to work

kotlin.NoSuchElementException: List is empty

when initialising

HttpClient

with

JsonFeature

on iOS 🤔 Not sure what's going wrong here but I suspect I have the wrong dependencies for target

iosMain

, being:

implementation("org.jetbrains.kotlinx:kotlinx-coroutines-core-iosx64:$kotlin_coroutines_version")
                implementation("org.jetbrains.kotlinx:kotlinx-serialization-runtime-native:$kotlin_serialization_version")
                implementation("io.ktor:ktor-client-ios:$ktor_version")
                implementation("io.ktor:ktor-client-json-iosx64:$ktor_version")

..it's hard to follow what the dependencies should be from Ktor documentation and examples. These don't seem to have kept pace with recent changes in meta-data driven identifiers and other refactoring.

Hi, does anyone know how to make something androids like BuildConfig.Debug but in ktor? I'm using gradle with groovy

Let's start a thread on how to use Ktor

HttpClient

in a

Worker

(background thread) on native 🙂

Does anyone else get this error regularly?

Maybe someone has already done this? Could someone help me a little bit? Then I'd be glad to make a PR for the ktor-examples on Github to have this there as well for the future.

Hey, I have an interesting challenge. I want to write a single-use web server. That is: create a Kotlin function that launches an embedded server, waits for a request and returns data from that request after stopping the server. The problem is blocking the function (the one that does embeddedServer) return until the request comes in, since routed

get

is deep in the DSL. I wonder what primitives you would suggest me to use to do the blocking.

Will cookies be properly processed if I do not specify

install(HttpCookies) {
            storage = AcceptAllCookiesStorage()
        }

on client init? Specifying this causes iOS MPP to crash, but I need cookies! ;/ P.S. Also I cannot extract it from headers directly 'cause it looks like ktor strips the "Set-Cookie" header before 😕

Is it always necessary to install the

ContentNegotiation

feature in the server to receive & send serialized (JSON encoded) objects? If the expected, exact content type is specified on both server and receiver, I don't see why

ContentNegotiation

needs to be a hard requirement - I thought this was only about dynamically negotiating a variable content & type at run-time?

What would be an idiomatic way to handle refreshing oauth tokens on demand using ktor-client ? i.e. the equivalent of this kind of okhttp things: https://gist.github.com/alex-shpak/da1e65f52dc916716930

I am trying to setup my ktor session cookie to contain a session UUID and the locale for the user. I have to following in `fun io.ktor.application.Application.main()`:

install(Sessions) {
		val sessionCookieKey = io.ktor.util.hex(environment.config.property("ktor.session.cookie.key").getString())
		fun configureCookie(): CookieSessionBuilder<*>.() -> Unit = {
			cookie.duration = null
			cookie.domain = null
			cookie.path = "/"
			cookie.secure = true
			cookie.httpOnly = true
			cookie.extensions["SameSite"] = "Strict"
			transform(SessionTransportTransformerMessageAuthentication(sessionCookieKey))
		}
		cookie<my.type.UuidV4>("SESSION_UUID", configureCookie())
		cookie<java.util.Locale>("LOCALE", configureCookie())
	}

I am getting an exception when I make a request to the server. (Which I will post as a reply.) After looking in to this for a while, it appears that the

SessionSerializerReflection.properties

contains

[var java.util.Locale.baseLocale: sun.util.locale.BaseLocale!, var java.util.Locale.localeExtensions: sun.util.locale.LocaleExtensions!, var java.util.Locale.hashCodeValue: <http://kotlin.Int|kotlin.Int>, var java.util.Locale.languageTag: kotlin.String!]

which are all

private transient

members of the

java.util.Locale

class. Is this a bug, or should I be doing this differently?

Hello, I'm working with

HttpClient

which executes a long request. This call is triggered via a

post

route, which looks something like this:

val http = HttpClient(Apache)

routing {
    post("/api/start-job") {
        <http://http.post|http.post><String>("<http://url-to-long-request>")
        call.respond(HttpStatusCode.Accepted, "job started")
    }
}

Sending a request to this route results in having to wait quite as the client makes a heavy request (it starts a job on another service). I'd like to simply send the request to

<http://url-to-long-request>

and immediately return the

202

with

"job started"

message. I could achieve this using an

Executor

and wrapping the

<http://http.post|http.post>

call, however I feel like that is not the right way to do this. Any suggestions on this?

Am I missing something? Any help is appreciated

Might be related to pulling out request values from

call

On the javascript side I am getting a similar error to someone earlier when using the HttpClient getting

List is empty.", cause_th0jdv$_0: null, name: "NoSuchElementException"

My gradle file has the following

compile ("org.jetbrains.kotlinx:kotlinx-serialization-runtime-common:${LibraryVersions.kotlin_js_serialization_version}")
    compile ("org.jetbrains.kotlinx:kotlinx-serialization-runtime-js:${LibraryVersions.kotlin_js_serialization_version}")
    compile ("io.ktor:ktor-client-core:${LibraryVersions.ktor_version}")
    compile ("io.ktor:ktor-client-js:${LibraryVersions.ktor_version}")
    compile ("io.ktor:ktor-client-json-js:${LibraryVersions.ktor_version}")
    compile ("io.ktor:ktor-client-serialization-js:${LibraryVersions.ktor_version}")
    compile ("io.ktor:ktor-client-auth-basic-js:${LibraryVersions.ktor_version}")

Has anyone managed to get this working?

@e5l Hi, can you provide some more detail on this? I'm facing this error, but unable to resolve for now.

install(HttpCookies) {
  storage = CustomStorage()
}

above code does not work, as

AcceptAllCookiesStorage

is provided as a default value for Config class. https://kotlinlang.slack.com/archives/C0A974TJ9/p1560522327059700?thread_ts=1560519079.059100&cid=C0A974TJ9

Anyone knows how to handle that?

How can I get the X509 client certificate from an HTTPS request like what I can do with the servlet framework using HttpServletRequest.getAttribute(“javax.servlet.request.X509Certificate”)?