wasm

@jsonstat-validator/wasm

The WebAssembly surface of jsonstat-validator — a thin JS wrapper over the Rust crate, exposing the same validate() signature as @jsonstat-validator/ts so the two are drop-in compatible.

The Wasm build is produced from the crate with wasm-pack (--target web); the wrapper in src/index.ts adapts the validate_json export to the TS ValidationResult shape.

Built on top of the same rules-manifest.json and corpus/cases.json as the TS and Rust surfaces, so all three produce identical findings on identical input (enforced by the parity tests).

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Install

npm install @jsonstat-validator/wasm

Usage

Browser / CDN

init() (no argument) fetches the adjacent .wasm over HTTP:

import { init, validate } from "@jsonstat-validator/wasm";

await init();                       // load the .wasm once
const result = validate(doc);       // doc may be an object OR a JSON string
console.log(result.valid, result.summary);

With a bundler (Vite/webpack/Rollup) the .wasm is emitted next to the JS automatically.

Node

The @jsonstat-validator/wasm/node entry auto-loads the .wasm bytes from disk on import, so no manual init() is needed, and it adds validateFile():

import { validate, validateFile } from "@jsonstat-validator/wasm/node";

const result = validate(doc);
const result2 = await validateFile("./my-cube.json");

(You can also use the main entry in Node by passing the bytes explicitly: await init(readFileSync(require.resolve("@jsonstat-validator/wasm/pkg/jsonstat_validator_bg.wasm"))).)

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Differences from @jsonstat-validator/ts

Concern	TS surface	Wasm surface
Lifecycle	none (pure JS)	await init() once (browser) / auto on Node
options.onFinding	supported (JS callback)	ignored (functions can't cross the JS↔wasm boundary)
options.budget	honored	ignored (Rust ValidateOptions skips unknown fields)
meta.durationMs	wall-clock ms (number)	always 0 — wasm32-unknown-unknown has no Instant, so timing is skipped
Finding shape (code/severity/path/message)	—	identical (parity-tested)

If you don't need the Wasm performance characteristics or wasm-pack toolchain, prefer @jsonstat-validator/ts — it has zero native/Rust dependencies.

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Building the Wasm artifact from source

# prerequisites (one-time)
rustup target add wasm32-unknown-unknown
cargo install wasm-pack

npm run build          # wasm-pack -t web -> packages/wasm/pkg, then tsc -> dist
npm test               # builds pkg and runs the TS↔Wasm corpus parity test

License

Apache-2.0.