0.18.0

What's changed

• New: kaml now supports working with polymorphic types where the type is specified as a type property in YAML (#11 - thanks to @gps for the suggestion).

  This means that there are now two styles available for working with polymorphic types (set YamlConfiguration.polymorphismStyle when creating an instance of Yaml):

  • using YAML tags to specify the type:

    servers:
      - !<frontend>
        hostname: a.mycompany.com
      - !<backend>
        database: db-1

  • using a type property to specify the type:

    servers:
      - type: frontend
        hostname: a.mycompany.com
      - type: backend
        database: db-1

  The fragments above could be generated with:

  @Serializable
  sealed class Server {
    @SerialName("frontend")
    @Serializable
    data class Frontend(val hostname: String)
  
    @SerialName("backend")
    @Serializable
    data class Backend(val database: String)
  }
  
  @Serializable
  data class Config(val servers: List<Server>)
  
  val config = Config(listOf(
    Frontend("a.mycompany.com"),
    Backend("db-1")
  ))
  
  val result = Yaml.default.stringify(Config.serializer(), config)
  
  println(result)

• Updated: kaml is now built against Kotlin 1.3.72.

• Changed: clearer exceptions will now be thrown in the following cases:

  • missing tag when deserializing a polymorphic type when using tags for polymorphic type information
  • unknown polymorphic type in tag or type property
  • missing required property for object

Upgrading

If you're using Gradle, reference kaml in your dependencies block like this:

implementation("com.charleskorn.kaml:kaml:0.18.0")

For other tools, refer to the Maven Central release page for more information.