Name Last Update
..
test Loading commit data...
.npmignore Loading commit data...
.travis.yml Loading commit data...
LICENSE Loading commit data...
README.md Loading commit data...
example.js Loading commit data...
formats.js Loading commit data...
index.js Loading commit data...
package.json Loading commit data...
require.js Loading commit data...

is-my-json-valid

A JSONSchema validator that uses code generation to be extremely fast

npm install is-my-json-valid

It passes the entire JSONSchema v4 test suite except for remoteRefs and maxLength/minLength when using unicode surrogate pairs.

build status

Usage

Simply pass a schema to compile it

var validator = require('is-my-json-valid')

var validate = validator({
  required: true,
  type: 'object',
  properties: {
    hello: {
      required: true,
      type: 'string'
    }
  }
})

console.log('should be valid', validate({hello: 'world'}))
console.log('should not be valid', validate({}))

// get the last list of errors by checking validate.errors
// the following will print [{field: 'data.hello', message: 'is required'}]
console.log(validate.errors)

You can also pass the schema as a string

var validate = validator('{"type": ... }')

Optionally you can use the require submodule to load a schema from __dirname

var validator = require('is-my-json-valid/require')
var validate = validator('my-schema.json')

Custom formats

is-my-json-valid supports the formats specified in JSON schema v4 (such as date-time). If you want to add your own custom formats pass them as the formats options to the validator

var validate = validator({
  type: 'string',
  required: true,
  format: 'only-a'
}, {
  formats: {
    'only-a': /^a+$/
  }
})

console.log(validate('aa')) // true
console.log(validate('ab')) // false

External schemas

You can pass in external schemas that you reference using the $ref attribute as the schemas option

var ext = {
  required: true,
  type: 'string'
}

var schema = {
  $ref: '#ext' // references another schema called ext
}

// pass the external schemas as an option
var validate = validator(schema, {schemas: {ext: ext}})

validate('hello') // returns true
validate(42) // return false

Filtering away additional properties

is-my-json-valid supports filtering away properties not in the schema

var filter = validator.filter({
  required: true,
  type: 'object',
  properties: {
    hello: {type: 'string', required: true}
  },
  additionalProperties: false
})

var doc = {hello: 'world', notInSchema: true}
console.log(filter(doc)) // {hello: 'world'}

Verbose mode outputs the value on errors

is-my-json-valid outputs the value causing an error when verbose is set to true

var validate = validator({
  required: true,
  type: 'object',
  properties: {
    hello: {
      required: true,
      type: 'string'
    }
  }
}, {
  verbose: true
})

validate({hello: 100});
console.log(validate.errors) // {field: 'data.hello', message: 'is the wrong type', value: 100, type: 'string'}

Greedy mode tries to validate as much as possible

By default is-my-json-valid bails on first validation error but when greedy is set to true it tries to validate as much as possible:

var validate = validator({
  type: 'object',
  properties: {
    x: {
      type: 'number'
    }
  },
  required: ['x', 'y']
}, {
  greedy: true
});

validate({x: 'string'});
console.log(validate.errors) // [{field: 'data.y', message: 'is required'},
                             //  {field: 'data.x', message: 'is the wrong type'}]

Error messages

Here is a list of possible message values for errors:

  • is required
  • is the wrong type
  • has additional items
  • must be FORMAT format (FORMAT is the format property from the schema)
  • must be unique
  • must be an enum value
  • dependencies not set
  • has additional properties
  • referenced schema does not match
  • negative schema matches
  • pattern mismatch
  • no schemas match
  • no (or more than one) schemas match
  • has a remainder
  • has more properties than allowed
  • has less properties than allowed
  • has more items than allowed
  • has less items than allowed
  • has longer length than allowed
  • has less length than allowed
  • is less than minimum
  • is more than maximum

Performance

is-my-json-valid uses code generation to turn your JSON schema into basic javascript code that is easily optimizeable by v8.

At the time of writing, is-my-json-valid is the fastest validator when running

If you know any other relevant benchmarks open a PR and I'll add them.

License

MIT