<img align="right" alt="Ajv logo" width="160" src="http://epoberezkin.github.io/ajv/images/ajv_logo.png">
# Ajv: Another JSON Schema Validator
The fastest JSON Schema validator for Node.js and browser with draft 6 support.
[![Build Status](https://travis-ci.org/epoberezkin/ajv.svg?branch=master)](https://travis-ci.org/epoberezkin/ajv)
[![npm version](https://badge.fury.io/js/ajv.svg)](https://www.npmjs.com/package/ajv)
[![npm@beta](https://img.shields.io/npm/v/ajv/beta.svg)](https://github.com/epoberezkin/ajv/tree/beta)
[![npm downloads](https://img.shields.io/npm/dm/ajv.svg)](https://www.npmjs.com/package/ajv)
[![Coverage Status](https://coveralls.io/repos/epoberezkin/ajv/badge.svg?branch=master&service=github)](https://coveralls.io/github/epoberezkin/ajv?branch=master)
[![Greenkeeper badge](https://badges.greenkeeper.io/epoberezkin/ajv.svg)](https://greenkeeper.io/)
[![Gitter](https://img.shields.io/gitter/room/ajv-validator/ajv.svg)](https://gitter.im/ajv-validator/ajv)
__Please note__: Ajv [version 6](https://github.com/epoberezkin/ajv/tree/beta) with [JSON Schema draft-07](http://json-schema.org/work-in-progress) support is released. Use `npm install ajv@beta` to install.
## Using version 5
[JSON Schema draft-06](https://trac.tools.ietf.org/html/draft-wright-json-schema-validation-01) is published.
[Ajv version 5.0.0](https://github.com/epoberezkin/ajv/releases/tag/5.0.0) that supports draft-06 is released. It may require either migrating your schemas or updating your code (to continue using draft-04 and v5 schemas).
__Please note__: To use Ajv with draft-04 schemas you need to explicitly add meta-schema to the validator instance:
```javascript
ajv.addMetaSchema(require('ajv/lib/refs/json-schema-draft-04.json'));
```
## Contents
- [Performance](#performance)
- [Features](#features)
- [Getting started](#getting-started)
- [Frequently Asked Questions](https://github.com/epoberezkin/ajv/blob/master/FAQ.md)
- [Using in browser](#using-in-browser)
- [Command line interface](#command-line-interface)
- Validation
- [Keywords](#validation-keywords)
- [Formats](#formats)
- [Combining schemas with $ref](#ref)
- [$data reference](#data-reference)
- NEW: [$merge and $patch keywords](#merge-and-patch-keywords)
- [Defining custom keywords](#defining-custom-keywords)
- [Asynchronous schema compilation](#asynchronous-schema-compilation)
- [Asynchronous validation](#asynchronous-validation)
- Modifying data during validation
- [Filtering data](#filtering-data)
- [Assigning defaults](#assigning-defaults)
- [Coercing data types](#coercing-data-types)
- API
- [Methods](#api)
- [Options](#options)
- [Validation errors](#validation-errors)
- [Related packages](#related-packages)
- [Packages using Ajv](#some-packages-using-ajv)
- [Tests, Contributing, History, License](#tests)
## Performance
Ajv generates code using [doT templates](https://github.com/olado/doT) to turn JSON schemas into super-fast validation functions that are efficient for v8 optimization.
Currently Ajv is the fastest and the most standard compliant validator according to these benchmarks:
- [json-schema-benchmark](https://github.com/ebdrup/json-schema-benchmark) - 50% faster than the second place
- [jsck benchmark](https://github.com/pandastrike/jsck#benchmarks) - 20-190% faster
- [z-schema benchmark](https://rawgit.com/zaggino/z-schema/master/benchmark/results.html)
- [themis benchmark](https://cdn.rawgit.com/playlyfe/themis/master/benchmark/results.html)
Performance of different validators by [json-schema-benchmark](https://github.com/ebdrup/json-schema-benchmark):
[![performance](https://chart.googleapis.com/chart?chxt=x,y&cht=bhs&chco=76A4FB&chls=2.0&chbh=32,4,1&chs=600x416&chxl=-1:|djv|ajv|json-schema-validator-generator|jsen|is-my-json-valid|themis|z-schema|jsck|skeemas|json-schema-library|tv4&chd=t:100,98,72.1,66.8,50.1,15.1,6.1,3.8,1.2,0.7,0.2)](https://github.com/ebdrup/json-schema-benchmark/blob/master/README.md#performance)
## Features
- Ajv implements full JSON Schema [draft 6](http://json-schema.org/) and draft 4 standards:
- all validation keywords (see [JSON Schema validation keywords](https://github.com/epoberezkin/ajv/blob/master/KEYWORDS.md))
- full support of remote refs (remote schemas have to be added with `addSchema` or compiled to be available)
- support of circular references between schemas
- correct string lengths for strings with unicode pairs (can be turned off)
- [formats](#formats) defined by JSON Schema draft 4 standard and custom formats (can be turned off)
- [validates schemas against meta-schema](#api-validateschema)
- supports [browsers](#using-in-browser) and Node.js 0.10-8.x
- [asynchronous loading](#asynchronous-schema-compilation) of referenced schemas during compilation
- "All errors" validation mode with [option allErrors](#options)
- [error messages with parameters](#validation-errors) describing error reasons to allow creating custom error messages
- i18n error messages support with [ajv-i18n](https://github.com/epoberezkin/ajv-i18n) package
- [filtering data](#filtering-data) from additional properties
- [assigning defaults](#assigning-defaults) to missing properties and items
- [coercing data](#coercing-data-types) to the types specified in `type` keywords
- [custom keywords](#defining-custom-keywords)
- draft-6 keywords `const`, `contains` and `propertyNames`
- draft-6 boolean schemas (`true`/`false` as a schema to always pass/fail).
- keywords `switch`, `patternRequired`, `formatMaximum` / `formatMinimum` and `formatExclusiveMaximum` / `formatExclusiveMinimum` from [JSON-schema extension proposals](https://github.com/json-schema/json-schema/wiki/v5-Proposals) with [ajv-keywords](https://github.com/epoberezkin/ajv-keywords) package
- [$data reference](#data-reference) to use values from the validated data as values for the schema keywords
- [asynchronous validation](#asynchronous-validation) of custom formats and keywords
Currently Ajv is the only validator that passes all the tests from [JSON Schema Test Suite](https://github.com/json-schema/JSON-Schema-Test-Suite) (according to [json-schema-benchmark](https://github.com/ebdrup/json-schema-benchmark), apart from the test that requires that `1.0` is not an integer that is impossible to satisfy in JavaScript).
## Install
```
npm install ajv
```
or to install [version 6](https://github.com/epoberezkin/ajv/tree/beta):
```
npm install ajv@beta
```
## <a name="usage"></a>Getting started
Try it in the Node.js REPL: https://tonicdev.com/npm/ajv
The fastest validation call:
```javascript
var Ajv = require('ajv');
var ajv = new Ajv(); // options can be passed, e.g. {allErrors: true}
var validate = ajv.compile(schema);
var valid = validate(data);
if (!valid) console.log(validate.errors);
```
or with less code
```javascript
// ...
var valid = ajv.validate(schema, data);
if (!valid) console.log(ajv.errors);
// ...
```
or
```javascript
// ...
var valid = ajv.addSchema(schema, 'mySchema')
.validate('mySchema', data);
if (!valid) console.log(ajv.errorsText());
// ...
```
See [API](#api) and [Options](#options) for more details.
Ajv compiles schemas to functions and caches them in all cases (using schema serialized with [fast-json-stable-stringify](https://github.com/epoberezkin/fast-json-stable-stringify) or a custom function as a key), so that the next time the same schema is used (not necessarily the same object instance) it won't be compiled again.
The best performance is achieved when using compiled functions returned by `compile` or `getSchema` methods (there is no additional function call).
__Please note__: every time a validation function or `ajv.validate` are called `errors` property is overwritten. You need to copy `errors` array reference to another variable if you want to use it later (e.g., in the callback). See [Validation errors](#validation-errors)
## Using in browser
You can require Ajv directly from
程序员Chino的日记
- 粉丝: 3756
- 资源: 5万+
最新资源
- 基于java+ssm+mysql的中学生课后服务的信息管理系统开题报告.docx
- 通过python爬虫获取人民网、新浪等网站新闻作为训练集 (源码+文档说明)
- 三相光伏并网逆变器simulink仿真 前级boost采用电导增量法实现最大功率追踪 后级逆变器在dq坐标系解耦实现控制 输出波形质量好,THD小于5% 直流侧电压稳定,纹波小于3%
- 基于java+ssm+vue+mysql的课程教学网站开题报告.docx
- 基于DSTATCOM无功补偿的风电并网模型 Matlab simulink 仿真简介: 1、2个风电:一个基于双馈风机DFIG、一个基于感应风机 2、仿真总时长30s,10s时,感应风机风速提高,无
- 基于java+ssm+vue+mysql的兰亭序图书管理系统开题报告.docx
- 风光不确定性场景生成与削减代码 风速使用weibull分布来描述 光照强度使用Beta分布描述 带入分布参数使用时序蒙托卡罗模拟生成大量基础场景 而后采用基于启发式的同步回代削减方法进行场景削减
- 毕业设计Python基于深度学习的甲状腺超声图像良恶性诊断算法研究源码+文档说明
- GIS开发openlayers基于webgis的全国公司分布统计以及查询系统 适合对象:gis初学者,爱好者 这个系统采用的webgis技术是openlayers+geoserver,开发工具vs20
- 全球二氧化碳排放情况数据集,提供了2000年至2022年间全球不同部门(包括工业、汽车、农业和家庭活动)二氧化碳排放,(包含17,686行记录和16个字段)
- SVPWM仿真和基于DSP28335的PIL(处理器在环) 仿真模型(将matlab仿真算法生成代码在DSP中在线运行返回数据给Matlab)验证算法可行性和实时性 对于数字信号处理很有用 (提供
- 模糊PID控制fuzzy- PID slx文件为模糊PID控制,模块齐全,方便使用,只需要修改成需要的信号输入即可,可替PID,适合新手学习
- 配电网重构 负荷损失matlab 采用matlab结合yalmip编写配电网重构程序,以IEEE33节点为例,网损和负荷损失作为目标函数,并且网络中包括一个sop,非常实用的程
- 半桥闭环LLC谐振变器仿真,含采用软启动策略,pi控制,柔化给定信号,三种方式波形对比波形图 50一类
- 步行机器人PID控制MATLAB仿真程序 采用了从拉格朗日力学推导的罗盘步态行走机器人的基本模型,并应用PID控制来跟踪所需的轨迹
- Python 与 MySQL 基础:构建数据驱动的应用程序-pdf
资源上传下载、课程学习等过程中有任何疑问或建议,欢迎提出宝贵意见哦~我们会及时处理!
点击此处反馈