Compatibility policies

A compatibility policy consists of rules Yandex Schema Registry uses to check the compatibility of the new schema with earlier versions at the namespace level.

You can select a compatibility policy when creating or updating the namespace. Compatibility policies are available for Protobuf and JSON Schema.

Protobuf schema compatibility policiesProtobuf schema compatibility policies

The following policies are available for Protobuf schemas:

• Confluent: Based on the best practices for the evolution of Protobuf schemas. For more on schema evolution, see this Protobuf guide.

• buf: Based on the Buf v1 standards. For more information about the checks, see this specification.

JSON schema compatibility policiesJSON schema compatibility policies

The following policies are available for JSON schemas:

• Confluent: Follows the Confluent Schema Registry standards and implements mathematically accurate compatibility checks. This policy does not allow adding or removing optional parameters in object fields. In certain cases, e.g., when working with queues, this limitation may be excessive.

• Optional friendly: Uses closed content model for the producer and open one, for the consumer, where only the producer schema is registered. The compatibility check involves converting the consumer schema from an open content model to a closed one and comparing it with the registered producer schemas. This policy allows adding or removing optional parameters in object fields while maintaining full transitive compatibility. Learn more about how this policy works.