ktor tests hanging

I’m added ktor to the Gradle project and the main code works find but I have problems with the tests. They are hanging

The server code:

package comfortable.data.server

import io.ktor.application.Application
import io.ktor.application.call
import io.ktor.http.ContentType
import io.ktor.response.respondText
import io.ktor.routing.get
import io.ktor.routing.routing
import io.ktor.server.engine.embeddedServer
import io.ktor.server.netty.Netty

fun Application.main() {
    val server = embeddedServer(Netty, port = 8080) {
        routing {
            get("/books") {
                val json = this::class.java.getResource("/books.json").readText()
                call.respondText(json, ContentType.Application.Json)
            }
        }
    }
    server.start(wait = true)
}

and the test code:

package comfortable.data.server

import io.ktor.application.Application
import org.junit.jupiter.api.Test
import org.junit.jupiter.api.Assertions.assertEquals

import io.ktor.server.testing.withTestApplication
import io.ktor.server.testing.handleRequest
import io.ktor.http.HttpMethod
import io.ktor.http.HttpStatusCode

/**
 * Testing class Server.
 */
class ServerTest {
    @Test
    fun testBookRequest() = withTestApplication(Application::main) {
        with(handleRequest(HttpMethod.Get, "/books")) {
            assertEquals(HttpStatusCode.OK, response.status())
            assertEquals(true, response?.content?.contains("Solaris"))
        }
    }
}

Running with gradle test -i: (after a while I use Ctrl-C to stop it)

> Task :test

comfortable.data.server.ServerTest > testBookRequest() STANDARD_OUT
    10:42:42.468 [Test worker] INFO ktor.test - No ktor.deployment.watch patterns specified, automatic reload is not active
    10:42:42.602 [Test worker] DEBUG io.netty.util.internal.logging.InternalLoggerFactory - Using SLF4J as the default logging framework
    10:42:42.613 [Test worker] DEBUG io.netty.channel.MultithreadEventLoopGroup - -Dio.netty.eventLoopThreads: 8
    10:42:42.686 [Test worker] DEBUG io.netty.channel.nio.NioEventLoop - -Dio.netty.noKeySetOptimization: false
    10:42:42.687 [Test worker] DEBUG io.netty.channel.nio.NioEventLoop - -Dio.netty.selectorAutoRebuildThreshold: 512
    10:42:42.754 [Test worker] DEBUG io.netty.util.internal.PlatformDependent0 - -Dio.netty.noUnsafe: false
    10:42:42.755 [Test worker] DEBUG io.netty.util.internal.PlatformDependent0 - Java version: 8
    10:42:42.760 [Test worker] DEBUG io.netty.util.internal.PlatformDependent0 - sun.misc.Unsafe.theUnsafe: available
    10:42:42.764 [Test worker] DEBUG io.netty.util.internal.PlatformDependent0 - sun.misc.Unsafe.copyMemory: available
    10:42:42.772 [Test worker] DEBUG io.netty.util.internal.PlatformDependent0 - java.nio.Buffer.address: available
    10:42:42.783 [Test worker] DEBUG io.netty.util.internal.PlatformDependent0 - direct buffer constructor: available
    10:42:42.786 [Test worker] DEBUG io.netty.util.internal.PlatformDependent0 - java.nio.Bits.unaligned: available, true
    10:42:42.787 [Test worker] DEBUG io.netty.util.internal.PlatformDependent0 - jdk.internal.misc.Unsafe.allocateUninitializedArray(int): unavailable prior to Java9
    10:42:42.787 [Test worker] DEBUG io.netty.util.internal.PlatformDependent0 - java.nio.DirectByteBuffer.<init>(long, int): available
    10:42:42.787 [Test worker] DEBUG io.netty.util.internal.PlatformDependent - sun.misc.Unsafe: available
    10:42:42.788 [Test worker] DEBUG io.netty.util.internal.PlatformDependent - -Dio.netty.tmpdir: /tmp (java.io.tmpdir)
    10:42:42.788 [Test worker] DEBUG io.netty.util.internal.PlatformDependent - -Dio.netty.bitMode: 64 (sun.arch.data.model)
    10:42:42.797 [Test worker] DEBUG io.netty.util.internal.PlatformDependent - -Dio.netty.noPreferDirect: false
    10:42:42.797 [Test worker] DEBUG io.netty.util.internal.PlatformDependent - -Dio.netty.maxDirectMemory: 2276458496 bytes
    10:42:42.797 [Test worker] DEBUG io.netty.util.internal.PlatformDependent - -Dio.netty.uninitializedArrayAllocationThreshold: -1
    10:42:42.800 [Test worker] DEBUG io.netty.util.internal.CleanerJava6 - java.nio.ByteBuffer.cleaner(): available
    10:42:42.851 [Test worker] DEBUG io.netty.util.internal.PlatformDependent - org.jctools-core.MpscChunkedArrayQueue: available
    10:42:42.919 [Test worker] INFO ktor.application - No ktor.deployment.watch patterns specified, automatic reload is not active
    10:42:43.006 [Test worker] INFO ktor.application - Responding at http://0.0.0.0:8080
    10:42:43.068 [Test worker] DEBUG io.netty.channel.DefaultChannelId - -Dio.netty.processId: 28808 (auto-detected)
    10:42:43.093 [Test worker] DEBUG io.netty.util.NetUtil - -Djava.net.preferIPv4Stack: false
    10:42:43.096 [Test worker] DEBUG io.netty.util.NetUtil - -Djava.net.preferIPv6Addresses: false
    10:42:43.103 [Test worker] DEBUG io.netty.util.NetUtil - Loopback interface: lo (lo, 0:0:0:0:0:0:0:1%lo)
    10:42:43.107 [Test worker] DEBUG io.netty.util.NetUtil - /proc/sys/net/core/somaxconn: 128
    10:42:43.109 [Test worker] DEBUG io.netty.channel.DefaultChannelId - -Dio.netty.machineId: 08:00:27:ff:fe:6e:7c:21 (auto-detected)
    10:42:43.127 [Test worker] DEBUG io.netty.util.internal.InternalThreadLocalMap - -Dio.netty.threadLocalMap.stringBuilder.initialSize: 1024
    10:42:43.128 [Test worker] DEBUG io.netty.util.internal.InternalThreadLocalMap - -Dio.netty.threadLocalMap.stringBuilder.maxSize: 4096
    10:42:43.201 [Test worker] DEBUG io.netty.util.ResourceLeakDetector - -Dio.netty.leakDetection.level: simple
    10:42:43.202 [Test worker] DEBUG io.netty.util.ResourceLeakDetector - -Dio.netty.leakDetection.targetRecords: 4
    10:42:43.301 [Test worker] DEBUG io.netty.buffer.PooledByteBufAllocator - -Dio.netty.allocator.numHeapArenas: 8
    10:42:43.303 [Test worker] DEBUG io.netty.buffer.PooledByteBufAllocator - -Dio.netty.allocator.numDirectArenas: 8
    10:42:43.305 [Test worker] DEBUG io.netty.buffer.PooledByteBufAllocator - -Dio.netty.allocator.pageSize: 8192
    10:42:43.313 [Test worker] DEBUG io.netty.buffer.PooledByteBufAllocator - -Dio.netty.allocator.maxOrder: 11
    10:42:43.318 [Test worker] DEBUG io.netty.buffer.PooledByteBufAllocator - -Dio.netty.allocator.chunkSize: 16777216
    10:42:43.321 [Test worker] DEBUG io.netty.buffer.PooledByteBufAllocator - -Dio.netty.allocator.tinyCacheSize: 512
    10:42:43.323 [Test worker] DEBUG io.netty.buffer.PooledByteBufAllocator - -Dio.netty.allocator.smallCacheSize: 256
    10:42:43.324 [Test worker] DEBUG io.netty.buffer.PooledByteBufAllocator - -Dio.netty.allocator.normalCacheSize: 64
    10:42:43.325 [Test worker] DEBUG io.netty.buffer.PooledByteBufAllocator - -Dio.netty.allocator.maxCachedBufferCapacity: 32768
    10:42:43.327 [Test worker] DEBUG io.netty.buffer.PooledByteBufAllocator - -Dio.netty.allocator.cacheTrimInterval: 8192
    10:42:43.329 [Test worker] DEBUG io.netty.buffer.PooledByteBufAllocator - -Dio.netty.allocator.useCacheForAllThreads: true
    10:42:43.377 [Test worker] DEBUG io.netty.buffer.ByteBufUtil - -Dio.netty.allocator.type: pooled
    10:42:43.381 [Test worker] DEBUG io.netty.buffer.ByteBufUtil - -Dio.netty.threadLocalDirectBufferSize: 0
    10:42:43.386 [Test worker] DEBUG io.netty.buffer.ByteBufUtil - -Dio.netty.maxThreadLocalCharBufferSize: 16384
<============-> 92% EXECUTING [1m 21s]
> :test > 8 tests completed
> :test > Executing test comfortable.data.server.ServerTest

[wildunne]

The tests start that Application.main method when you call testApp in your test. server.start never response, so that never finishes.

I had the same issue, and the same workaround. In order to get it working you need a new main file, which looks something like this:

import io.ktor.server.engine.commandLineEnvironment
import io.ktor.server.engine.embeddedServer
import io.ktor.server.netty.Netty

fun main(args: Array<String>) {
    embeddedServer(Netty, commandLineEnvironment(args)).start()
}

This is, in my estimation, a documentation bug more than anything

[user5145]

because at the beginning everything is difficult and usually people who run into this issue are just starting their adventure with ktor and maybe kotlin too, i’ve put @wildunne and @Nachtfeuer 's code together

Main.kt:

fun main(args: Array<String>) {
    embeddedServer(Netty, commandLineEnvironment(args)).start()
}

Application.kt:

fun Application.module() {
    routing {
        get("/test") {
            call.respondText("Hello login!!!", ContentType.Text.Plain)
        }
    }
}

ApplicationTest:

class ApplicationTest {
    @Test
    fun testRequestsOK() = withTestApplication(Application::module) {
        with(handleRequest(HttpMethod.Get, "/test")) {
            assertEquals(HttpStatusCode.OK, response.status())
            assertEquals("Hello login!!!", response.content)
        }
    }
}