XmlUtilSampleTest.kt

package com.coats.d3.sap

import io.kotest.core.spec.style.StringSpec
import io.kotest.matchers.shouldBe
import kotlinx.serialization.KSerializer
import kotlinx.serialization.SerialName
import kotlinx.serialization.Serializable
import kotlinx.serialization.descriptors.PrimitiveKind
import kotlinx.serialization.descriptors.PrimitiveSerialDescriptor
import kotlinx.serialization.descriptors.SerialDescriptor
import kotlinx.serialization.encoding.Decoder
import kotlinx.serialization.encoding.Encoder
import nl.adaptivity.xmlutil.serialization.XML
import nl.adaptivity.xmlutil.serialization.XmlElement
import java.time.LocalDate
import java.time.format.DateTimeFormatter

class XmlUtilSampleTest: StringSpec() {
    init {
        "Can deserialize an TestDto with a zero date" {
            val xml = "<ScheduleLine><DeliveryDate>00.00.0000</DeliveryDate><QuantityAvailable>25</QuantityAvailable></ScheduleLine>"
            val deser = XML.decodeFromString(TestDto.serializer(), xml)

            deser.deliveryDate shouldBe null
            deser shouldBe TestDto(
                deliveryDate = null
            )
        }
    }
}

@Serializable
@SerialName("ScheduleLine")
data class TestDto(
    @XmlElement(true)
    @SerialName("DeliveryDate")
    @Serializable(with = OptionalDateSerializerImpl::class)
    val deliveryDate: LocalDate? = null
)

open class OptionalDateSerializer(format: String, private val nullMarker: String, private val replacement: LocalDate? = null) :
    KSerializer<LocalDate?> {
    override val descriptor: SerialDescriptor = PrimitiveSerialDescriptor("LocalDate:$format", PrimitiveKind.STRING)
    private val formatter = DateTimeFormatter.ofPattern(format)
    override fun serialize(encoder: Encoder, value: LocalDate?) {
        encoder.encodeString(value?.format(formatter) ?: nullMarker)
    }
    override fun deserialize(decoder: Decoder): LocalDate? {
        val dateString = decoder.decodeString()
        return if (dateString.isBlank() || (dateString == nullMarker)) replacement else LocalDate.parse(dateString, formatter)
    }
}

object OptionalDateSerializerImpl : OptionalDateSerializer("dd.MM.yyyy", "00.00.0000")