Registry / validation / json-schema-library

json-schema-library

library11.5.0jsnpmunverified

json-schema-library is a customizable, hackable, and highly compliant JSON Schema validator and utility library for JavaScript/TypeScript, fully supporting JSON Schema drafts 04, 06, 07, 2019-09, and 2020-12. Version 11.5.0 is current (released 2024), with frequent updates. Unlike faster or more minimal validators, it prioritizes extensibility: you can customize drafts, add keyword extensions, and traverse schemas via SchemaNode. It's the most compliant validator per Bowtie reports, runs in Node and browser, and ships TypeScript types. Designed for developers building custom tools around JSON Schema, not just validation.

validation

npm install json-schema-library

github ↗package ↗homepage ↗

INSTALL

IMPORT

SIG · JSON-SCHEMA-LIBRAR

json-schema-library

validationjavascriptv11.5.0

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.

compileSchema

✓ import { compileSchema } from 'json-schema-library'

✗ const { compileSchema } = require('json-schema-library'); compileSchema(schema);

ESM-only since v11. For TypeScript, use import syntax. CommonJS require may fail in some bundlers or Node versions.

SchemaNode

✓ import { SchemaNode } from 'json-schema-library'

TypeScript type used for the result of compileSchema. Not available as a runtime value.

draft04

✓ import { draft04 } from 'json-schema-library'

✗ import { Draft04 } from 'json-schema-library'

Draft imports are lowercase, camelCase. Use draftXX to access draft-specific validation functions.

default

✓ import jsonSchemaLibrary from 'json-schema-library'

✗ import * as jsonSchemaLibrary from 'json-schema-library'

Default export is the library namespace; prefer named imports for tree-shaking.

Compiles a JSON Schema into a SchemaNode, validates data, generates default data, and navigates subschemas via JSON Pointer.

import { compileSchema } from 'json-schema-library'; const schema = { type: 'object', properties: { name: { type: 'string' }, age: { type: 'number', minimum: 0 } }, required: ['name'] }; const compiled = compileSchema(schema); // Validate data const data = { name: 'Alice', age: 30 }; const result = compiled.validate(data); console.log('Valid:', result.valid); // true // Generate default data const defaultData = compiled.getData(); console.log(defaultData); // {} // Access a node by JSON Pointer const nameNode = compiled.getNode('/properties/name'); console.log(nameNode.schema); // { type: 'string' }

Debug

Known issues

breakingVersion 11 dropped CommonJS support. require('json-schema-library') may fail in older Node or non-ESM environments.

fix

Use ES modules: static import or dynamic import(). For legacy CommonJS, stick with v10.x.

affects: >=11.0.0

deprecatedThe `validate` method on SchemaNode now returns an object with `valid`, `errors`, `annotations`. The old method returning boolean is removed.

fix

Update code to destructure result: const { valid, errors } = schemaNode.validate(data);

affects: >=8.0.0

gotchacompileSchema expects a JSON Schema object, not a JSON string or file path. Attempting to pass a string will throw a confusing error.

fix

Parse JSON strings with JSON.parse() first, or import JSON files using import assertions (build tools) or fs.readFileSync with JSON.parse.

affects: *

gotchaWhen using draft-04, the `$schema` keyword in the schema object may be ignored if not set correctly; the library auto-detects based on draft. But if you explicitly set draft via options, it overrides $schema.

fix

Explicitly pass draft option: compileSchema(schema, { draft: 'draft-04' }) to force a specific draft.

affects: *

deprecatedgetNode() with a single string argument is deprecated. Use the overload with options object for better type safety.

fix

Change getNode('#/foo') to getNode('#/foo', { data: {} }) to avoid deprecated behavior.

affects: >=10.0.0

Errors

Common errors & fixes

TypeError: schemaNode.validate is not a function

You may have imported a version that doesn't export SchemaNode correctly, or you're using v11 and trying to call validate on a raw schema object.

fix

Ensure you call compileSchema(schema) first and use the returned SchemaNode. Check import: import { compileSchema } from 'json-schema-library'.

Cannot find module 'json-schema-library' or its corresponding type declarations

Missing @types/json-schema-library (unnecessary since v10 ships types) or incorrect module resolution in tsconfig.

fix

Update tsconfig.json: set 'moduleResolution' to 'node' or 'node16', and 'esModuleInterop' to true. Also ensure json-schema-library is installed.

Uncaught Error: Invalid schema: property 'properties' must be an object

The schema passed to compileSchema is invalid JSON Schema structure (likely malformed).

fix

Validate your schema first with a JSON Schema validator or check that properties is an object (not array or string).

ReferenceError: self is not defined

The library is trying to access the global object in a Node environment where `self` doesn't exist. This is a known bug in older versions (pre-v10).

fix

Upgrade to v10+ or use a polyfill for self: globalThis.self = globalThis;

Upgrade

Version history

11.5.0latest on npm

Audit

Dependencies

lodashrequiredDeep clone, merge, and utility functions used internally

uuidoptionalUnique identifiers for internal schema node tracking

Agent activity

27 hits · last 30 days

node

Amazon

Resources

githubhttps://github.com/sagold/json-schema-library ↗

packagejson-schema-library ↗

homepagehttps://github.com/sagold/json-schema-library ↗