Hi there,
we just finished our JSON-Schema-Validator module for vertx. It's based on the Java-Implementation from here:
https://github.com/fge/json-schema-validatorWith JSON-Schema you can make schemas for JSON-Objects, so you can validate them against this schema. It's like what xsd is for xml. Check JSON-Schema out here:
http://json-schema.org/With the vertx-module you can register schemas and then send a message with a JSON-String to the module and let it validate against a schema.
We use it to validate incoming JSON-Parameters in our REST-Api and give the user a nice error when he sends an invalid request.
The module is already in the module-registry and the whole project can be found here:
https://github.com/campudus/vertx-json-schema-validatorhth
Max