Table of Contents

• About
• Installation
• Usage
• Customization
• Differences from validator-ajv8

About

@rjsf/validator-ata plugs ata-validator into react-jsonschema-form as a drop-in alternative to @rjsf/validator-ajv8. The public API mirrors validator-ajv8 so swapping is a one-line change in the validator import. Error format, custom-format hook, custom validation, and error transformation all work the same way.

ata is a JSON Schema validator that targets Draft 2020-12 (98.5% spec compliance, 95.3% schemasafe pass rate) and is Standard Schema compliant. Its differentiators relative to AJV: pattern checks are RE2-backed (no ReDoS surface), and schemas can be compiled at build time for environments where bundle size or CSP restricts runtime codegen.

Installation

npm install @rjsf/validator-ata ata-validator

ata-validator is a peer of this package; install it alongside.

Usage

import Form from '@rjsf/core';
import validator from '@rjsf/validator-ata';

<Form schema={schema} validator={validator} />;

Customization

import { customizeValidator } from '@rjsf/validator-ata';

const validator = customizeValidator({
  customFormats: {
    'phone-us': /\(?\d{3}\)?[\s-]?\d{3}[\s-]?\d{4}$/,
    'area-code': /\d{3}/,
  },
  ataOptionsOverrides: {
    verbose: true,
  },
});

customizeValidator accepts:

• customFormats — same shape as validator-ajv8. Values may be a RegExp, an anchored regex source string, or a (value: string) => boolean predicate.
• ataOptionsOverrides — plain ata-validator options spread on top of the defaults; use this to flip coerceTypes, removeAdditional, verbose, or abortEarly.
• additionalMetaSchemas — extra schemas registered via Validator#addSchema for cross-schema $ref resolution.
• extenderFn — hook applied against a freshly-built Validator (e.g. for adding additional formats or schemas in one place).
• suppressDuplicateFiltering — passthrough to the RJSF error processor; same semantics as in validator-ajv8.

A Localizer may be supplied as the second argument. ata error objects use the same field names as AJV (keyword, instancePath, schemaPath, params, message, parentSchema), so localizers that mutate message in place port across without changes. The pre-quote dance that the AJV validator runs against ajv-i18n is intentionally not replicated here — ata's error params are frozen, and the existing locale catalogues for AJV are not portable to ata's keyword set.

Differences from validator-ajv8

The ValidatorType contract is identical, and the shared @rjsf/utils schema test suite passes against this validator with the deltas below. Behavior outside of this list mirrors validator-ajv8.

• Precompiled validators are not yet wired through. The compileSchemaValidators and createPrecompiledValidator entrypoints exposed by validator-ajv8 are slated for a follow-up release that adapts ata's bundleStandalone codegen to the RJSF-expected ValidatorFunctions shape.
• ajvOptionsOverrides, ajvFormatOptions, AjvClass have no equivalents and are intentionally not accepted. ataOptionsOverrides replaces the first; built-in formats are always installed and don't require an opt-in flag.
• isValid and rawValidation deep-clone formData before passing it to ata. ata's default-applier writes default values into the input object during validation, while AJV treats validation as a pure operation. The clone preserves the AJV contract RJSF expects when probing data through repeated isValid calls (oneOf/anyOf option resolution).
• Custom-keyword extensions (e.g. ajv-errors, ajv-merge-patch) have no ata-side counterpart yet. Schemas using these keywords will validate (ata silently ignores unknown keywords) but the extension semantics are not applied.

Contributing

See the monorepo CONTRIBUTING.md. Issues and PRs welcome on either the validator package or ata-validator itself.