I try to configure `KotlinSerializationJsonEncoder...

# spring

[marzelwidmer]

I try to configure KotlinSerializationJsonEncoder in my SpringBoot app. have maybe somebody a hint what is wrong in my configuration ….
I get the following exception when I call my backend service.

org.springframework.web.reactive.function.client.WebClientResponseException: 200 OK from UNKNOWN ; nested exception is kotlinx.serialization.json.internal.JsonDecodingException: Unexpected JSON token at offset 7: Encountered an unknown key 'fooBar'.
Use 'ignoreUnknownKeys = true' in 'Json {}' builder to ignore unknown keys.
JSON input: {
    "fooBar": "123,345.....

I try to configured it like this:

@Configuration
class WebConfig : WebFluxConfigurer {
    //<https://docs.spring.io/spring-framework/docs/current/reference/html/web-reactive.html#webflux-config-message-codecs>
    override fun configureHttpMessageCodecs(configurer: ServerCodecConfigurer) {
        KotlinSerializationJsonEncoder(
            Json {
                ignoreUnknownKeys = true
            }
        )
    }
}

[marzelwidmer]

the Good thing is the Jackson gone when I check my stacktrace 🙂

[Jonas Bark]

override fun configureHttpMessageCodecs(configurer: ServerCodecConfigurer) {
        KotlinSerializationJsonEncoder(
            Json {
                ignoreUnknownKeys = true
            }
        )
    }

I don’t think that this has any effect, as in neither a value is returned nor the configurer is used