A cross-browser / node.js validator with JSONSchema compatibility as the primary goal.

The core of revalidator is simple and succinct: revalidator.validate(obj, schema):

  var revalidator = require('revalidator');

  console.dir(revalidator.validate(someObject, {
    properties: {
      url: {
        description: 'the url the object should be stored at',
        type: 'string',
        pattern: '^/[^#%&*{}\\:<>?\/ ] $',
        required: true
      },
      challenge: {
        description: 'a means of protecting data (insufficient for production, used as example)',
        type: 'string',
        minLength: 5
      },
      body: {
        description: 'what to store at the url',
        type: 'any',
        default: null
      }
    }
  }));

This will return with a value indicating if the obj conforms to the schema. If it does not, a descriptive object will be returned containing the errors encountered with validation.

  {
    valid: true // or false
    errors: [/* Array of errors if valid is false */]
  }

In the browser, the validation function is exposed on window.validate by simply including revalidator.js.

  $ curl http://npmjs.org/install.sh | sh

  $ [sudo] npm install revalidator

revalidator takes json-schema as input to validate objects.

This will return with a value indicating if the obj conforms to the schema. If it does not, a descriptive object will be returned containing the errors encountered with validation.

{
  valid: true // or false
  errors: [/* Array of errors if valid is false */]
}

• validateFormats: Enforce format constraints (default true)
• validateFormatsStrict: When validateFormats is true treat unrecognized formats as validation errors (default false)
• validateFormatExtensions: When validateFormats is true also validate formats defined in validate.formatExtensions (default true)
• additionalProperties: When additionalProperties is true allow additional unvisited properties on the object. (default true)
• cast: Enforce casting of some types (for integers/numbers are only supported) when it's possible, e.g. "42" => 42, but "forty2" => "forty2" for the integer type.

For a property an value is that which is given as input for validation where as an expected value is the value of the below fields

If true, the value should not be undefined

{ required: true }

If false, the value must not be an empty string

{ allowEmpty: false }

The type of value should be equal to the expected value

{ type: 'string' }
{ type: 'number' }
{ type: 'integer' }
{ type: 'array' }
{ type: 'boolean' }
{ type: 'object' }
{ type: 'null' }
{ type: 'any' }
{ type: ['boolean', 'string'] }

The expected value regex needs to be satisfied by the value

{ pattern: /^[a-z] $/ }

The length of value must be greater than or equal to expected value

{ maxLength: 8 }

The length of value must be lesser than or equal to expected value

{ minLength: 8 }

Value must be greater than or equal to the expected value

{ minimum: 10 }

Value must be lesser than or equal to the expected value

{ maximum: 10 }

Value may not be empty

{ allowEmpty: false }

Value must be greater than expected value

{ exclusiveMinimum: 9 }

Value must be lesser than expected value

{ exclusiveMaximum: 11 }

Value must be divisible by expected value

{ divisibleBy: 5 }
{ divisibleBy: 0.5 }

Value must contain more than expected number of items

{ minItems: 2 }

Value must contain fewer than expected number of items

{ maxItems: 5 }

Value must hold a unique set of values

{ uniqueItems: true }

Value must be present in the array of expected values

{ enum: ['month', 'year'] }

Value must be a valid format

{ format: 'url' }
{ format: 'email' }
{ format: 'ip-address' }
{ format: 'ipv6' }
{ format: 'date-time' }
{ format: 'date' }
{ format: 'time' }
{ format: 'color' }
{ format: 'host-name' }
{ format: 'utc-millisec' }
{ format: 'regex' }

Value must conform to constraint denoted by expected value

{ conform: function (v) {
    if (v%3==1) return true;
    return false;
  }
}

Value is valid only if the dependent value is valid

{
  town: { required: true, dependencies: 'country' },
  country: { maxLength: 3, required: true }
}

We also allow nested schema

{
  properties: {
    title: {
      type: 'string',
      maxLength: 140,
      required: true
    },
    author: {
      type: 'object',
      required: true,
      properties: {
        name: {
          type: 'string',
          required: true
        },
        email: {
          type: 'string',
          format: 'email'
        }
      }
    }
  }
}

We also allow custom messages for different constraints

{
  type: 'string',
  format: 'url'
  messages: {
    type: 'Not a string type',
    format: 'Expected format is a url'
  }

{
  conform: function () { ... },
  message: 'This can be used as a global message'
}

All tests are written with vows and should be run with npm:

  $ npm test