Why does Apache Avro use JSON to define a schema?

Question

Why does Apache Avro use JSON to define a schema? Why not use IDL directly to define a schema? What is the advantage in transforming IDL to JSON?

Answer 1

Because JSON is trivially serializable, ubiquitous, and the original schema definition mechanism.

Bear in mind that Avro is platform-neutral, and it must continue to support platforms and libraries that use the original schema def--and that's the schema that's sent in the message. If you started transmitting only IDL then everything would break.

Answer 2

Why reinvent the wheel and define an IDL in some proprietary format if you can use a popular existing format. XML would also fit this bill but XML is very verbose.