Spring webtestclient serializes dates to timestamps instead of dates - kotlin

Question

I am trying to check if the data I get back from the webtestclient is the same as what I expect. But the ZonedDateTime from the User data class is not just shown as a date but as a timestamp while I have applied Jackson to the webtestclient codecs. Example: 2021-12-09T16:39:43.225207700+01:00 is converted to 1639064383.225207700 while I expect nothing to change. Could someone maybe explain what I am doing wrong. (Using this jackson config when calling this endpoint outside of the test gives the date not as timestamp)
WebTestClientUtil:
object WebTestClientUtil {
fun webTestClient(routerFunction: RouterFunction<ServerResponse>): WebTestClient {
return WebTestClient
.bindToRouterFunction(routerFunction)
.configureClient()
.codecs { configurer: ClientCodecConfigurer ->
configurer.defaultCodecs().jackson2JsonEncoder(Jackson2JsonEncoder(objectMapper, MediaType.APPLICATION_JSON))
configurer.defaultCodecs().jackson2JsonDecoder(Jackson2JsonDecoder(objectMapper, MediaType.APPLICATION_JSON))
}
.build()
}
}
Testcase:
#Test
fun `get user when given correct data`() {
val user = GlobalMocks.mockedUser
coEvery { userRepository.getUserWithData(any()) } returns user
val result = webTestClient.get()
.uri("/api/v1/user/${user.userId}")
.exchange()
.expectStatus().is2xxSuccessful
.expectBody<Result>().returnResult().responseBody?.payload
assertEquals(user, result)
}
data class Result(
val payload: User
)
Jackson config:
class JacksonConfig {
companion object {
val serializationDateFormat: DateTimeFormatter = DateTimeFormatter.ofPattern("yyyy-MM-dd'T'HH:mm:ssXX")
val deserializationDateFormat: DateTimeFormatter = DateTimeFormatter.ofPattern("yyyy-MM-dd'T'HH:mm[:ss][XXX][X]")
val objectMapper = jacksonObjectMapper().applyDefaultSettings()
private fun ObjectMapper.applyDefaultSettings() =
apply {
disable(DeserializationFeature.ADJUST_DATES_TO_CONTEXT_TIME_ZONE)
disable(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS)
disable(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES)
enable(DeserializationFeature.READ_UNKNOWN_ENUM_VALUES_USING_DEFAULT_VALUE)
setSerializationInclusion(JsonInclude.Include.NON_NULL)
registerModule(Jdk8Module())
registerModule(ParameterNamesModule())
registerModule(JsonComponentModule())
registerModule(
JavaTimeModule().apply {
addSerializer(ZonedDateTime::class.java, ZonedDateTimeSerializer(serializationDateFormat))
addDeserializer(ZonedDateTime::class.java, ZonedDateTimeDeserializer())
}
)
}
}
class ZonedDateTimeDeserializer : JsonDeserializer<ZonedDateTime>() {
override fun deserialize(jsonParser: JsonParser, deserializationContext: DeserializationContext): ZonedDateTime {
val epochTime = jsonParser.text.toLongOrNull()
return if (epochTime != null) {
ZonedDateTime.ofInstant(
Instant.ofEpochSecond(epochTime),
currentZone
)
} else {
ZonedDateTime.parse(jsonParser.text, deserializationDateFormat)
}
}
}
}
EDIT: Also found this issue which makes me think that it might have something to do with bindToRouterFunction.

Answer 1

You need to define an ObjectMapper bean so that the auto-configured one is not used:
#Configuration(proxyBeanMethods = false)
class JacksonConfiguration {
companion object {
val serializationDateFormat: DateTimeFormatter = DateTimeFormatter.ofPattern("yyyy-MM-dd'T'HH:mm:ssXX")
val deserializationDateFormat: DateTimeFormatter = DateTimeFormatter.ofPattern("yyyy-MM-dd'T'HH:mm[:ss][XXX][X]")
}
#Bean
fun objectMapper() = jacksonObjectMapper().applyDefaultSettings ()
private fun ObjectMapper.applyDefaultSettings() =
apply {
disable(DeserializationFeature.ADJUST_DATES_TO_CONTEXT_TIME_ZONE)
disable(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS)
disable(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES)
enable(DeserializationFeature.READ_UNKNOWN_ENUM_VALUES_USING_DEFAULT_VALUE)
setSerializationInclusion(JsonInclude.Include.NON_NULL)
registerModule(Jdk8Module())
registerModule(ParameterNamesModule())
registerModule(JsonComponentModule())
registerModule(
JavaTimeModule().apply {
addSerializer(ZonedDateTime::class.java, ZonedDateTimeSerializer(serializationDateFormat))
addDeserializer(ZonedDateTime::class.java, ZonedDateTimeDeserializer())
}
)
}
class ZonedDateTimeDeserializer : JsonDeserializer<ZonedDateTime>() {
override fun deserialize(jsonParser: JsonParser, deserializationContext: DeserializationContext): ZonedDateTime {
val epochTime = jsonParser.text.toLongOrNull()
return if (epochTime != null) {
ZonedDateTime.ofInstant(
Instant.ofEpochSecond(epochTime),
currentZone
)
} else {
ZonedDateTime.parse(jsonParser.text, deserializationDateFormat)
}
}
}
}