JSON Schema validation for Human 👨‍🎤

Main goal of this library is to provide relevant error messages like the following:

Differences from better-ajv-errors

• Only targets current Node LTS releases.
• AJV 8 support.
• Default errors stack the error message at the top of the location instead of the bottom.
  • This helps eliminate long blocks of ^^^^^^ pointers.
• Addition of a colorize option for disabling colorization in format: cli output.
• Up-to-date dependencies.

Installation

$ npm i better-ajv-errors

Also make sure that you installed ajv package to validate data against JSON schemas.

Usage

First, you need to validate your payload with ajv. If it's invalid then you can pass validate.errors object into better-ajv-errors.

import Ajv from 'ajv';
import betterAjvErrors from 'better-ajv-errors';
// const Ajv = require('ajv');
// const betterAjvErrors = require('better-ajv-errors');

// You need to pass `{ jsonPointers: true }` for older versions of ajv
const ajv = new Ajv();

// Load schema and data
const schema = ...;
const data = ...;

const validate = ajv.compile(schema);
const valid = validate(data);

if (!valid) {
  const output = betterAjvErrors(schema, data, validate.errors);
  console.log(output);
}

API

betterAjvErrors(schema, data, errors, [options])

Returns formatted validation error to print in console. See options.format for further details.

schema

Type: Object

The JSON Schema you used for validation with ajv

data

Type: Object

The JSON payload you validate against using ajv

errors

Type: Array

Array of ajv validation errors

options

Type: Object

colorize

Type: boolean Default: true

When disabled, if you are outputting cli formatting it will be without colorized or styled content.

format

Type: string Default: cli Values: cli js

Use default cli output format if you want to print beautiful validation errors like following:

Or, use js if you are planning to use this with some API. Your output will look like following:

[
  {
    start: { line: 6, column: 15, offset: 70 },
    end: { line: 6, column: 26, offset: 81 },
    error: '/content/0/type should be equal to one of the allowed values: panel, paragraph, ...',
    suggestion: 'Did you mean paragraph?',
  },
];

indent

Type: number null Default: null

If you have an unindented JSON payload and you want the error output indented.

This option have no effect when using the json option.

json

Type: string null Default: null

Raw JSON payload used when formatting codeframe. Gives accurate line and column listings.