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Apache Avro

Apache Avro is an Open Source schema and IDL language from Apache. It is often used with Apache Kafka or other big data tools.

Converts the Concerto model to an Avro .avdl file. Use avro-tools.jar to convert AVDL to a JSON Avro schema.

concerto compile --model test.cto --target avro

Sample Output

protocol MyProtocol {

import idl "concerto@1.0.0.avdl";

record Person {
string email;
union { null, string } dob;




  1. $identifier and $timestamp cannot be used as a property names, so these are converted to _identifier and _timestamp.
  2. DateTime is stored as a long with the @logicalType("timestamp-micros") annotation
  3. No super types, so properties across the inheritence hierarchy are merged into each record
  4. Relationships are represented as string
  5. Scalars are unboxed as properties