/// Jackson module that marshals ByteArray as a JSON array of unsigned bytes,
/// matching how Rust serde encodes Vec<u8> on the wire.
/// Jackson's default writes ByteArray as a Base64 string, which Rust serde rejects
/// with "invalid type: string, expected a sequence".
private val byteArrayModule = com.fasterxml.jackson.databind.module.SimpleModule().apply {
addSerializer(
ByteArray::class.java,
object : com.fasterxml.jackson.databind.ser.std.StdSerializer<ByteArray>(ByteArray::class.java) {
override fun serialize(
value: ByteArray,
gen: com.fasterxml.jackson.core.JsonGenerator,
provider: com.fasterxml.jackson.databind.SerializerProvider,
) {
gen.writeStartArray()
for (b in value) gen.writeNumber(b.toInt() and 0xff)
gen.writeEndArray()
}
},
)
addDeserializer(
ByteArray::class.java,
object : com.fasterxml.jackson.databind.deser.std.StdDeserializer<ByteArray>(ByteArray::class.java) {
override fun deserialize(
parser: com.fasterxml.jackson.core.JsonParser,
ctx: com.fasterxml.jackson.databind.DeserializationContext,
): ByteArray {
val node = parser.codec.readTree<com.fasterxml.jackson.databind.JsonNode>(parser)
return when {
node.isArray -> ByteArray(node.size()) { i -> node.get(i).asInt().toByte() }
node.isTextual -> java.util.Base64.getDecoder().decode(node.asText())
else -> ByteArray(0)
}
}
},
)
}
private val mapper = jacksonObjectMapper()
.registerModule(com.fasterxml.jackson.datatype.jdk8.Jdk8Module())
.registerModule(byteArrayModule)
.registerModule(
com.fasterxml.jackson.module.kotlin.KotlinModule.Builder()
.configure(com.fasterxml.jackson.module.kotlin.KotlinFeature.NullIsSameAsDefault, true)
.configure(com.fasterxml.jackson.module.kotlin.KotlinFeature.NullToEmptyCollection, true)
.configure(com.fasterxml.jackson.module.kotlin.KotlinFeature.NullToEmptyMap, true)
.build(),
)
.setPropertyNamingStrategy(PropertyNamingStrategies.SNAKE_CASE)
.setSerializationInclusion(com.fasterxml.jackson.annotation.JsonInclude.Include.NON_NULL)
.configure(com.fasterxml.jackson.databind.DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false)