.config/coc/extensions/node_modules/coc-prettier/node_modules/table/node_modules/ajv/README.md

   1 <img align="right" alt="Ajv logo" width="160" src="https://ajv.js.org/img/ajv.svg">
   2
   3 &nbsp;
   4
   5 # Ajv JSON schema validator
   6
   7 The fastest JSON validator for Node.js and browser.
   8
   9 Supports JSON Schema draft-06/07/2019-09/2020-12 (draft-04 is supported in [version 6](https://github.com/ajv-validator/ajv/tree/v6)) and JSON Type Definition [RFC8927](https://datatracker.ietf.org/doc/rfc8927/).
  10
  11 [![build](https://github.com/ajv-validator/ajv/workflows/build/badge.svg)](https://github.com/ajv-validator/ajv/actions?query=workflow%3Abuild)
  12 [![npm](https://img.shields.io/npm/v/ajv.svg)](https://www.npmjs.com/package/ajv)
  13 [![npm downloads](https://img.shields.io/npm/dm/ajv.svg)](https://www.npmjs.com/package/ajv)
  14 [![Coverage Status](https://coveralls.io/repos/github/ajv-validator/ajv/badge.svg?branch=master)](https://coveralls.io/github/ajv-validator/ajv?branch=master)
  15 [![Gitter](https://img.shields.io/gitter/room/ajv-validator/ajv.svg)](https://gitter.im/ajv-validator/ajv)
  16 [![GitHub Sponsors](https://img.shields.io/badge/$-sponsors-brightgreen)](https://github.com/sponsors/epoberezkin)
  17
  18 ## Platinum sponsors
  19
  20 [<img src="https://ajv.js.org/img/mozilla.svg" width="45%">](https://www.mozilla.org)<img src="https://ajv.js.org/img/gap.svg" width="8%">[<img src="https://ajv.js.org/img/reserved.svg" width="45%">](https://opencollective.com/ajv)
  21
  22 ## Contributing
  23
  24 More than 100 people contributed to Ajv, and we would love to have you join the development. We welcome implementing new features that will benefit many users and ideas to improve our documentation.
  25
  26 Please review [Contributing guidelines](./CONTRIBUTING.md) and [Code components](https://ajv.js.org/components.html).
  27
  28 ## Documentation
  29
  30 All documentation is available on the [Ajv website](https://ajv.js.org).
  31
  32 Some useful site links:
  33 - [Getting started](https://ajv.js.org/guide/getting-started.html)
  34 - [JSON Schema vs JSON Type Definition](https://ajv.js.org/guide/schema-language.html)
  35 - [API reference](https://ajv.js.org/api.html)
  36 - [Strict mode](https://ajv.js.org/strict-mode.html)
  37 - [Standalone validation code](https://ajv.js.org/standalone.html)
  38 - [Security considerations](https://ajv.js.org/security.html)
  39 - [Command line interface](https://ajv.js.org/packages/ajv-cli.html)
  40 - [Frequently Asked Questions](https://ajv.js.org/faq.html)
  41
  42 ## <a name="sponsors"></a>Please [sponsor Ajv development](https://github.com/sponsors/epoberezkin)
  43
  44 Since I asked to support Ajv development 40 people and 6 organizations contributed via GitHub and OpenCollective - this support helped receiving the MOSS grant!
  45
  46 Your continuing support is very important - the funds will be used to develop and maintain Ajv once the next major version is released.
  47
  48 Please sponsor Ajv via:
  49
  50 - [GitHub sponsors page](https://github.com/sponsors/epoberezkin) (GitHub will match it)
  51 - [Ajv Open Collective️](https://opencollective.com/ajv)
  52
  53 Thank you.
  54
  55 #### Open Collective sponsors
  56
  57 <a href="https://opencollective.com/ajv"><img src="https://opencollective.com/ajv/individuals.svg?width=890"></a>
  58
  59 <a href="https://opencollective.com/ajv/organization/0/website"><img src="https://opencollective.com/ajv/organization/0/avatar.svg"></a>
  60 <a href="https://opencollective.com/ajv/organization/1/website"><img src="https://opencollective.com/ajv/organization/1/avatar.svg"></a>
  61 <a href="https://opencollective.com/ajv/organization/2/website"><img src="https://opencollective.com/ajv/organization/2/avatar.svg"></a>
  62 <a href="https://opencollective.com/ajv/organization/3/website"><img src="https://opencollective.com/ajv/organization/3/avatar.svg"></a>
  63 <a href="https://opencollective.com/ajv/organization/4/website"><img src="https://opencollective.com/ajv/organization/4/avatar.svg"></a>
  64 <a href="https://opencollective.com/ajv/organization/5/website"><img src="https://opencollective.com/ajv/organization/5/avatar.svg"></a>
  65 <a href="https://opencollective.com/ajv/organization/6/website"><img src="https://opencollective.com/ajv/organization/6/avatar.svg"></a>
  66 <a href="https://opencollective.com/ajv/organization/7/website"><img src="https://opencollective.com/ajv/organization/7/avatar.svg"></a>
  67 <a href="https://opencollective.com/ajv/organization/8/website"><img src="https://opencollective.com/ajv/organization/8/avatar.svg"></a>
  68 <a href="https://opencollective.com/ajv/organization/9/website"><img src="https://opencollective.com/ajv/organization/9/avatar.svg"></a>
  69
  70 ## Performance
  71
  72 Ajv generates code to turn JSON Schemas into super-fast validation functions that are efficient for v8 optimization.
  73
  74 Currently Ajv is the fastest and the most standard compliant validator according to these benchmarks:
  75
  76 - [json-schema-benchmark](https://github.com/ebdrup/json-schema-benchmark) - 50% faster than the second place
  77 - [jsck benchmark](https://github.com/pandastrike/jsck#benchmarks) - 20-190% faster
  78 - [z-schema benchmark](https://rawgit.com/zaggino/z-schema/master/benchmark/results.html)
  79 - [themis benchmark](https://cdn.rawgit.com/playlyfe/themis/master/benchmark/results.html)
  80
  81 Performance of different validators by [json-schema-benchmark](https://github.com/ebdrup/json-schema-benchmark):
  82
  83 [![performance](https://chart.googleapis.com/chart?chxt=x,y&cht=bhs&chco=76A4FB&chls=2.0&chbh=62,4,1&chs=600x416&chxl=-1:|ajv|@exodus&#x2F;schemasafe|is-my-json-valid|djv|@cfworker&#x2F;json-schema|jsonschema&chd=t:100,69.2,51.5,13.1,5.1,1.2)](https://github.com/ebdrup/json-schema-benchmark/blob/master/README.md#performance)
  84
  85 ## Features
  86
  87 - Ajv implements JSON Schema [draft-06/07/2019-09/2020-12](http://json-schema.org/) standards (draft-04 is supported in v6):
  88   - all validation keywords (see [JSON Schema validation keywords](https://ajv.js.org/json-schema.html))
  89   - [OpenAPI](https://github.com/OAI/OpenAPI-Specification/blob/master/versions/3.0.3.md) extensions:
  90     - NEW: keyword [discriminator](https://ajv.js.org/json-schema.md#discriminator).
  91     - keyword [nullable](https://ajv.js.org/json-schema.md#nullable).
  92   - full support of remote references (remote schemas have to be added with `addSchema` or compiled to be available)
  93   - support of recursive references between schemas
  94   - correct string lengths for strings with unicode pairs
  95   - JSON Schema [formats](https://ajv.js.org/guide/formats.html) (with [ajv-formats](https://github.com/ajv-validator/ajv-formats) plugin).
  96   - [validates schemas against meta-schema](https://ajv.js.org/api.html#api-validateschema)
  97 - NEW: supports [JSON Type Definition](https://datatracker.ietf.org/doc/rfc8927/):
  98   - all keywords (see [JSON Type Definition schema forms](https://ajv.js.org/json-type-definition.html))
  99   - meta-schema for JTD schemas
 100   - "union" keyword and user-defined keywords (can be used inside "metadata" member of the schema)
 101 - supports [browsers](https://ajv.js.org/guide/environments.html#browsers) and Node.js 10.x - current
 102 - [asynchronous loading](https://ajv.js.org/guide/managing-schemas.html#asynchronous-schema-loading) of referenced schemas during compilation
 103 - "All errors" validation mode with [option allErrors](https://ajv.js.org/options.html#allerrors)
 104 - [error messages with parameters](https://ajv.js.org/api.html#validation-errors) describing error reasons to allow error message generation
 105 - i18n error messages support with [ajv-i18n](https://github.com/ajv-validator/ajv-i18n) package
 106 - [removing-additional-properties](https://ajv.js.org/guide/modifying-data.html#removing-additional-properties)
 107 - [assigning defaults](https://ajv.js.org/guide/modifying-data.html#assigning-defaults) to missing properties and items
 108 - [coercing data](https://ajv.js.org/guide/modifying-data.html#coercing-data-types) to the types specified in `type` keywords
 109 - [user-defined keywords](https://ajv.js.org/guide/user-keywords.html)
 110 - additional extension keywords with [ajv-keywords](https://github.com/ajv-validator/ajv-keywords) package
 111 - [\$data reference](https://ajv.js.org/guide/combining-schemas.html#data-reference) to use values from the validated data as values for the schema keywords
 112 - [asynchronous validation](https://ajv.js.org/guide/async-validation.html) of user-defined formats and keywords
 113
 114 ## Install
 115
 116 To install version 7:
 117
 118 ```
 119 npm install ajv
 120 ```
 121
 122 ## <a name="usage"></a>Getting started
 123
 124 Try it in the Node.js REPL: https://runkit.com/npm/ajv
 125
 126 In JavaScript:
 127
 128 ```javascript
 129 // or ESM/TypeScript import
 130 import Ajv from "ajv"
 131 // Node.js require:
 132 const Ajv = require("ajv")
 133
 134 const ajv = new Ajv() // options can be passed, e.g. {allErrors: true}
 135
 136 const schema = {
 137   type: "object",
 138   properties: {
 139     foo: {type: "integer"},
 140     bar: {type: "string"}
 141   },
 142   required: ["foo"],
 143   additionalProperties: false,
 144 }
 145
 146 const validate = ajv.compile(schema)
 147 const valid = validate(data)
 148 if (!valid) console.log(validate.errors)
 149 ```
 150
 151 Learn how to use Ajv and see more examples in the [Guide: getting started](https://ajv.js.org/guide/getting-started.html)
 152
 153 ## Changes history
 154
 155 See [https://github.com/ajv-validator/ajv/releases](https://github.com/ajv-validator/ajv/releases)
 156
 157 **Please note**: [Changes in version 7.0.0](https://github.com/ajv-validator/ajv/releases/tag/v7.0.0)
 158
 159 [Version 6.0.0](https://github.com/ajv-validator/ajv/releases/tag/v6.0.0).
 160
 161 ## Code of conduct
 162
 163 Please review and follow the [Code of conduct](./CODE_OF_CONDUCT.md).
 164
 165 Please report any unacceptable behaviour to ajv.validator@gmail.com - it will be reviewed by the project team.
 166
 167 ## Security contact
 168
 169 To report a security vulnerability, please use the
 170 [Tidelift security contact](https://tidelift.com/security).
 171 Tidelift will coordinate the fix and disclosure. Please do NOT report security vulnerabilities via GitHub issues.
 172
 173 ## Open-source software support
 174
 175 Ajv is a part of [Tidelift subscription](https://tidelift.com/subscription/pkg/npm-ajv?utm_source=npm-ajv&utm_medium=referral&utm_campaign=readme) - it provides a centralised support to open-source software users, in addition to the support provided by software maintainers.
 176
 177 ## License
 178
 179 [MIT](./LICENSE)