0003: Use Boon for JSON Schema Validation

Date: 2024-07-29

Status

Accepted

Context

The converter must handle various versions of the JSON Schema specification, as users may provide schemas conforming to different drafts (e.g., Draft 4, Draft 7, 2020-12). To ensure the integrity of the JSON Schema to GraphQL conversion, a robust validation step is necessary. This validator must be able to:

1. Support Multiple Schema Versions: Correctly identify and validate against different drafts of the JSON Schema specification.
2. Be Performant: Validation should be fast to not impede the real-time conversion process.
3. Provide Clear Errors: When validation fails, the errors should be descriptive enough to guide the user in fixing their schema.
4. Integrate with Rust: The validator must be a Rust crate to integrate seamlessly into the existing WASM module.

Decision

We will use the boon crate for all JSON Schema validation within the Rust converter.

Boon is a comprehensive Rust library for JSON Schema validation that explicitly supports multiple specification versions, including Draft 4, 6, 7, 2019-09, and 2020-12. This aligns perfectly with our requirement for multi-version compatibility. The library will be used to validate any incoming JSON Schema before attempting conversion.

Consequences

Positive

• Multi-Version Compatibility: Boon’s primary strength is its support for multiple JSON Schema drafts. This eliminates the need for us to write complex, version-aware validation logic and ensures broad compatibility for our users.
• Performance: Being a native Rust crate, boon offers excellent performance suitable for real-time validation within the WASM environment.
• Correctness: The crate is well-tested and focuses on correctly implementing the JSON Schema specification, incrintake_processng the reliability of our conversion tool.
• Simplified Logic: By offloading the complexity of validation, our core converter logic can focus solely on the transformation from a valid schema to GraphQL SDL.

Negative

• New Dependency: We are introducing another external dependency into the project, which we will need to manage and keep updated.
• API Specificity: The development team will need to learn the specific API and error-reporting mechanisms of boon to integrate it effectively.