Avro validation

[sarthakNITT]

Why do we need this improvement?

While working on adding Avro validation in the AsyncAPI CLI
(asyncapi/cli#1833
), we noticed that proper validation needs to happen in this repository.

Currently, Avro schemas with invalid definitions (e.g. type: notexisting) are parsed without errors, which causes the CLI to incorrectly report them as valid.

cc: @M3lkior @dalelane
Please let me know if I can start working on this.

How will this change help?

• Detect invalid Avro schemas early
• Allow CLI and other tools to report correct validation errors
• Improve correctness when using Avro with AsyncAPI

Screenshots

No response

How could it be implemented/designed?

Add semantic validation for Avro schemas during parsing
Report clear validation errors for invalid types and structures
Expose validation results so downstream tools (like the CLI) can reuse them

🚧 Breaking changes

No

👀 Have you checked for similar open issues?

• I checked and didn't find a similar issue

🏢 Have you read the Contributing Guidelines?

• I have read the Contributing Guidelines

Are you willing to work on this issue?

Yes I am willing to submit a PR!

[github-actions]

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[dalelane]

Thanks for the suggestion.

It would help to understand what types of invalid schemas you observed not being treated as invalid, as what I can see from https://github.com/asyncapi/avro-schema-parser?tab=readme-ov-file#validation-of-avro-schemas suggests that there is an intent to validate schemas already.

Essentially, I'm saying that you might have found a bug, rather than this being a new feature.

(Either way, I'm not disagreeing it sounds like we need to do something - but I think it would help to clarify what that something is before we get started on it)

[sarthakNITT]

@dalelane I traced this back to the original CLI issue: asyncapi/cli#1813, asyncapi/cli#1929

In short, invalid Avro schemas (e.g. type: notexisting) are currently accepted because avro-schema-parser does not perform semantic Avro validation during validate(). Structurally valid YAML/JSON passes, and no error is surfaced to downstream tools like the CLI.

So this looks like a parser-level validation gap rather than a CLI issue. The missing piece seems to be enforcing Avro spec semantics during validation and exposing proper errors.

If this matches your understanding, I’m happy to work on a PR in this repo.

[Varadraj75]

hey @sarthakNITT ,
i would like to know , are u still working on this issue or not.

[sarthakNITT]

hey @Varadraj75 , I was waiting for someones response from your side. I am familiar with the codebase, would start working on it and hit a pr by tomorrow.