FormDataConverterTest.kt

package com.example

import io.ktor.application.ApplicationCall
import io.ktor.application.call
import io.ktor.application.install
import io.ktor.features.ContentConverter
import io.ktor.features.ContentNegotiation
import io.ktor.http.*
import io.ktor.request.ApplicationReceiveRequest
import io.ktor.request.receive
import io.ktor.response.respond
import io.ktor.routing.post
import io.ktor.routing.routing
import io.ktor.server.testing.handleRequest
import io.ktor.server.testing.setBody
import io.ktor.server.testing.withTestApplication
import io.ktor.util.pipeline.PipelineContext
import org.junit.Test
import kotlin.test.assertEquals
import kotlin.test.assertNotNull

class FormDataConverter : ContentConverter {
    override suspend fun convertForReceive(context: PipelineContext<ApplicationReceiveRequest, ApplicationCall>): Any? {
        TODO("not implemented")
    }

    override suspend fun convertForSend(
        context: PipelineContext<Any, ApplicationCall>,
        contentType: ContentType,
        value: Any
    ): Any? {
        TODO("not implemented")
    }

}

class FormDataConverterTest {
    @Test
    fun testMap() = withTestApplication {
        val uc = "\u0422"
        application.install(ContentNegotiation) {
            register(ContentType.Application.FormUrlEncoded, FormDataConverter())
        }
        application.routing {
            post("/") {
                val map = call.receive<Map<*, *>>()
                val text = map.entries.joinToString { "${it.key}=${it.value}" }
                call.respond(text)
            }
        }

        handleRequest(HttpMethod.Post, "/") {
            addHeader("Accept", "text/plain")
            addHeader("Content-Type", "application/x-www-form-urlencoded")
            setBody("""id=1&title=Hello,%20World!&unicode=$uc""")
        }.response.let { response ->
            assertEquals(HttpStatusCode.OK, response.status())
            assertNotNull(response.content)
            assertEquals(listOf("""id=1, title=Hello, World!, unicode=$uc"""), response.content!!.lines())
            val contentTypeText = assertNotNull(response.headers[HttpHeaders.ContentType])
            assertEquals(ContentType.Text.Plain.withCharset(Charsets.UTF_8), ContentType.parse(contentTypeText))
        }
    }

    @Test
    fun testEntity() = withTestApplication {
        val uc = "\u0422"
        application.install(ContentNegotiation) {
            register(ContentType.Application.FormUrlEncoded, FormDataConverter())
        }

        application.routing {
            post("/") {
                val entity = call.receive<MyEntity>()
                call.respond(entity.toString())
            }

        }

        handleRequest(HttpMethod.Post, "/") {
            addHeader("Content-Type", "application/x-www-form-urlencoded")
            setBody("""id=777&name=Cargo&children[0][item]=Qube&children[0][quantity]=1&children[1][item]=Sphere&children[1][quantity]=2&children[1][item]=$uc&children[1][quantity]=3""")
        }.response.let { response ->
            assertEquals(HttpStatusCode.OK, response.status())
            assertNotNull(response.content)
            assertEquals(
                listOf("""MyEntity(id=777, name=Cargo, children=[ChildEntity(item=Qube, quantity=1), ChildEntity(item=Sphere, quantity=2), ChildEntity(item=$uc, quantity=3)])"""),
                response.content!!.lines()
            )
            val contentTypeText = assertNotNull(response.headers[HttpHeaders.ContentType])
            assertEquals(ContentType.Text.Plain.withCharset(Charsets.UTF_8), ContentType.parse(contentTypeText))
        }

    }
}


data class MyEntity(val id: Int, val name: String, val children: List<ChildEntity>)
data class ChildEntity(val item: String, val quantity: Int)