Example for replacing a complete Validator with a custom implementation

[christianplatta1012]

Hi,

My problem:
I'm using the confluent_kafka python library and I want to use the schema validation feature when producing and consuming messages.
Internally confluent_kafka is using your nice jsonschema library but it seems as if this really slows down the kafka clients (example: producing 10,000 messages without validation takes about 0.0815 seconds and 0.4899 seconds with validation!). We have several million message each day, this slowdown will add up...

What I want to accomplish:
There is also a Rust-based JSON schema validator for python (https://pypi.org/project/jsonschema-rs/) which is - like most Rust-based libraries - blazingly fast and supports the kind of JSON schemas we use. I want to replace the "draft2020-12" validator implementation from jsonschema with the jsonschema-rs implementation.

What I don't understand
At first I thought it is just a matter of subclassing the Draft202012Validator or implementing the Validator Protocol with a class that delegates to the jsonschema-rs implementation and calling jsonschema.validators.validates to register it (so that confluent-kafka will use my implementation for "draft2020-12" schemas)

But then I've found this https://python-jsonschema.readthedocs.io/en/stable/creating/#creating-or-extending-validator-classes and subclassing directly even creates a warning messages. I don't quite understand the 'validators' parameter in jsonschema.validators.create or jsonschema.validators.extend. Do I have to define a validate method for each json schema element? I want just replace the complete validate method with a finished implementation... Is this possible? Can you point me to an example on how to use your intended way for creating or extending to do this?

Best regards,
Christian

[Julian]

Hi there. Realistically I doubt I'll have much time to think this through for you. I can definitely confirm that subclassing is not a supported public API. I'm available for consulting if need be (feel free to reach out directly if you'd like), otherwise maybe someone else will come by with some specific advice.