json-lint-d-ts

library1.2.2jsnpmunverified

Lint JSON files against TypeScript declaration files. Current stable version is 1.2.2, released optionally. It validates JSON files by comparing them to .d.ts definitions, ensuring type safety without running TypeScript. Supports generation of .d.ts files from JSON samples (via quicktype) and from HTTP endpoints. Key differentiator: unlike JSON Schema validators, it uses TypeScript type definitions directly as the schema source.

testing serialization

npm install json-lint-d-ts

github ↗package ↗

INSTALL

IMPORT

SIG · JSON-LINT-D-TS

json-lint-d-ts

testingjavascriptv1.2.2

harness data pending

Install & Compatibility

Where this runs

No compatibility data collected yet for this library.

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

validate

✓ import { validate } from "json-lint-d-ts";

✗ const validate = require("json-lint-d-ts").validate;

ESM default; CommonJS require works but destructuring is not supported directly.

generate

✓ import { generate } from "json-lint-d-ts";

✗ import { generate } from "json-lint-d-ts/generate";

Both validate and generate are top-level exports.

generateAsync

✓ import { generateAsync } from "json-lint-d-ts";

✗ import { generateAsync } from "json-lint-d-ts/src/generateAsync";

Available since v1.2.0 for HTTP-based generation.

Validates a JSON file against a TypeScript declaration file using the validate function.

import { validate } from "json-lint-d-ts"; const result = validate([ ["./hello.json", "./hello.d.ts"], ]); // Result shows any type errors console.log(result);

json-lint-d-ts --version

Debug

Known issues

gotcha.d.ts file must define a 'type Root' for validation to work; otherwise validation may silently succeed or fail unexpectedly.

fix

Ensure your .d.ts file exports a type named Root. For example: type Root = YourInterface;

affects: >=1.0.0

deprecatedgenerate function uses quicktype under the hood and may have breaking changes when quicktype updates.

fix

Monitor quicktype changelog for breaking changes, or pin quicktype version if needed.

affects: >=1.1.0

gotchaValidation errors are returned as strings, not structured objects. Parsing error messages for programmatic use is brittle.

fix

Use string matching or regex to extract error details; consider wrapping validate in a custom parser.

affects: >=1.0.0

gotchagenerateAsync does not support Bearer tokens or custom headers for HTTP endpoints; only raw URL fetch without authentication.

fix

Pre-fetch data with your own fetch() and pass the JSON body directly to generate.

affects: >=1.2.0

Errors

Common errors & fixes

TypeError: Cannot read properties of undefined (reading 'Symbol(quick-type)')

Missing or incompatible quicktype version when using generate.

fix

Install quicktype as a peer dependency: yarn add -D quicktype

Error: No type Root found in declaration file.

The .d.ts file does not define a type named Root.

fix

Add `type Root = YourMainType;` to the declaration file.

TypeError: validate(...).then is not a function

Treating validate as async when it is synchronous.

fix

Use result = validate([...]) without await; validate returns an array directly.

Upgrade

Version history

1.2.2latest on npm

Audit

Dependencies

typescriptoptionalUsed for type checking JSON against .d.ts files during validation

quicktypeoptionalUsed for generating TypeScript declarations from JSON samples

Agent activity

4 hits · last 30 days

node

Resources

githubhttps://github.com/vlashchanka/json-lint-d-ts ↗

packagehttps://www.npmjs.com/package/json-lint-d-ts ↗