Un URN JSON

un-urn-json.kt

import com.fasterxml.jackson.databind.JsonNode
import com.fasterxml.jackson.databind.ObjectMapper
import com.fasterxml.jackson.databind.node.ObjectNode
import com.fasterxml.jackson.databind.node.TextNode

private val typeMap = mutableMapOf<String, String>()

private fun parseReferences(jsonNode: JsonNode, path: String) {
    val ITEMS = "items"
    val ID = "id"
    val PROPERTIES = "properties"
    val ADDITIONAL_PROPERTIES = "additionalProperties"
    val REF = "\$ref"

    var currPath = path

    if (jsonNode.has(ID)) {
        typeMap.put(jsonNode.get(ID).asText(), currPath)
        val properties: JsonNode = jsonNode.get(PROPERTIES)
        val fields: Iterator<Map.Entry<String, JsonNode>> = properties.fields()
        currPath += "/$PROPERTIES"
        while (fields.hasNext()) {
            val entry = fields.next()
            parseReferences(entry.value, currPath + "/" + entry.key)
        }
    } else if (jsonNode.has(ITEMS)) {
        val item: JsonNode = jsonNode.get(ITEMS)
        parseReferences(item, "$currPath/$ITEMS")
    } else if (jsonNode.has(REF)) {
        val objectNode = jsonNode as ObjectNode
        objectNode.set(REF, TextNode(typeMap.get(jsonNode.get(REF).asText())))
    } else if (jsonNode.has(ADDITIONAL_PROPERTIES)) {
        val additionalProperties: JsonNode = jsonNode.get(ADDITIONAL_PROPERTIES)
        parseReferences(additionalProperties, "$currPath/$ADDITIONAL_PROPERTIES")
    }
}

/**
 * Remove URN from JSON, and replace with # type references
 */
fun parseReference(json: String): String {
    val jaxbObjectMapper = ObjectMapper()
    val root: JsonNode = jaxbObjectMapper.readTree(json)
    parseReferences(root, "#")
    return jaxbObjectMapper.writerWithDefaultPrettyPrinter().writeValueAsString(root)
}