Fully automatic generation of play-json serializers

libraryDependencies += "ru.makkarpov" %% "pray-json" % VERSION

Features (see tests):

• fully recursive generation — no need for intermediate serializer implicits;
  • generation can be restricted using @requireImplicit annotation.
  • implicit search for Format[T] happens also in a companion object of T, and, if companion itself is inside of object — in all outer objects.
  • recursive structures are also supported.
• generation of case class serializers:
  • simple case classes;
  • renamed fields using @key annotation. it also can transform key names to snake_case automatically;
  • support for default values;
  • support for Optional fields.
  • in some APIs fields should be serialized as strings even if they aren't strings. This is also supported;
  • inline formatting of case classes with single parameter
• generation of sealed serializers:
  • automatically added type field to distinguish between cases;
  • name and value of type field can be customized with annotations;
  • support for fallback cases;
• generation of serializers for collections:
  • Traversables: Seqs, Sets, ...;
  • Maps: custom key types are supported via KeyFormat[K];
  • Options (when not inside of a case class) are serialized either as [] or [something].
• Enumerations:
  • Values are serialized as strings with their name;
  • ValueSets are serialized as array of strings.