validator.js

Powerful objects and strings validation in javascript for Node and modern browsers (evergreen browsers).

Version

1.2.3

Status

Build Status Bitdeli Badge

License

MIT - See LICENSE.md

Install

bower install validator.js

Summary

General usage

$ npm install -g validator.js

Then

var Validator = require( 'validator.js' );
<script src="../validator.js"></script>
<script>
    console.log(Validator);
</script>

Validate a string

var is = require( 'validator.js' ).Assert;
var validator = require( 'validator.js' ).validator();

validator.validate( 'foo', is.ofLength( { min: 4 } ) );
validator.validate( 'foo', [ is.ofLength( { min: 4 } ), is.email() ] );

will return true if validation passes, a Violation's array otherwise.

Validate an object

var is = require( 'validator.js' ).Assert;
var validator = require( 'validator.js' ).validator();

var object = {
    name: 'john doe',
    email: 'wrong@email',
    firstName: null,
    phone: null
  },
  constraint = {
    name: [ is.notBlank(), is.ofLength( { min: 4, max: 25 } ) ],
    email: is.email(),
    firstName: is.notBlank(),
    phone: is.notBlank()
  };

validator.validate( object, constraint );

will return true if validation passes, { email: [ Violation ], firstname: [ Violation ] } in this case.

Validation groups

With same objects than above, just by adding validation groups:

  constraint = {
    name:      [ is.notBlank(), is( 'edit' ).ofLength( { min: 4, max: 25 } ) ],
    email:     is.email(),
    firstname: is( [ 'edit', 'register'] ).notBlank(),
    phone:     is( 'edit' ).notBlank()
  };

validator.validate( object, constraint, 'edit' );

will return true in this case { firstname: [ Violation ], phone: [ Violation ] }.

There are two special groups: "Any" and "Default". Validating against "Any" group will validate against all Asserts, regardless their groups. Validating against "Default" group will only validate against Asserts that do not have a validation group.

Bind a constraint to an object

validator.bind( object, constraint );
validator.validate( object, groups );

Under the hood, by default, a _validatorjsConstraint key will be created in object in order to store here the constraint. You could override this default key name by passing an option to Validator constructor.

Documentation

Assert definition

An assert implements Assert Interface, and is an assertion that your string or object property must pass during validation process. There are several Asserts built in Validator.js (see below), but you can implement yours for your needs using the Callback() assert (see below).

var length = is.ofLength( { min: 10 } );
try {
  length.check( 'foo' );
} catch ( violation ) {
}

Constraint definition

A Constraint is a set of asserts nodes that would be used to validate an object.

var length = is.ofLength( { min: 10 } );
var notBlank = is.notBlank();
var constraint = validator.constraint( { foo: length, bar: notBlank } );

constraint.check( { foo: 'foo', bar: 'bar' } );

Strict Constraint validation

By default, Validator.js checks properties that are defined in the Constraint object and exists on the validated object unless the constraint is Required. If you want a strict validation (ie ensure that every) Constraint node is valid, you'll have to pass an optional parameter to your Constraint:

var object = {
  foo: 'foo',
  bar: 'bar'
};

var constraint = validator.constraint( {
  foo: is.notBlank(),
  bar: is.notBlank(),
  baz: is.notBlank()
}, { strict: true });

constraint.check( object );

will return a HaveProperty Violation, saying that baz property does not exist in validated object. Without { strict: true } this check would return true.

Deep required validation

By default, a Required constraint fails if the parent property exists in the validated object and the property doesn't. To force Validator.js to take into account all Required constraints, no matter the validated object, you have to enable the deepRequired option:

var object = { };

var constraint = validator.constraint({
  foo: {
    bar: is.required()
  }
}, { deepRequired: true });

constraint.check(object);

will return a HaveProperty Violation, saying that foo property does not exist.

This option also works when Collection is used, but doesn't enforce a non empty array on the validated object.

Available asserts

Additional asserts via extras.js

Community-driven asserts

You can extend validator.js with more asserts should you need them. There are several extra asserts built by the community that seamlessly integrate with this package. See the Extending section for more information.

Collection Assert

Collection Assert is quite special yet powerful. It allows you to validate an object's array by checking each one of them against a constraint.

Here is an example of test suite test showing how this assert works:

it( 'Collection', function () {
  var itemConstraint = validator.constraint( { foobar: is.notNull(), foobaz: is.notNull() } ),
    object = {
      foo: null,
      items: [
        { foobar: null, foobaz: 'foo', fooqux: null },
        { foobar: 'bar', foobaz: 'baz' },
        { foobar: null, foobaz: null }
      ]
    },
    constraint = {
      foo: is.notNull(),
      items: [ is.collection( itemConstraint ), is.count( 2 ) ]
    };

  var result = validator.validate( object, constraint );
  expect( result ).to.have.key( 'foo' );
  expect( result ).to.have.key( 'items' );
  expect( result.items[ 0 ] ).to.have.key( '0' );
  expect( result.items[ 0 ] ).to.have.key( '2' );
  expect( result.items[ 0 ][ 0 ] ).to.have.key( 'foobar' );
  expect( result.items[ 0 ][ 0 ] ).not.to.have.key( 'foobaz' );
  expect( result.items[ 0 ][ 2 ] ).to.have.key( 'foobar' );
  expect( result.items[ 0 ][ 2 ] ).to.have.key( 'foobaz' );
  expect( result.items[ 1 ] ).to.be.a( Violation );
  expect( result.items[ 1 ].assert ).to.be( 'Count' );
} )

Callback Assert

This assert allows you to add the custom rules / assert you want. Just give a callback function that will be called with the value to be tested against. Return true for validation success, everything else if there is an error.

Here is an example from test suite test showing how this assert works:

it( 'Callback', function () {
  assert = is.callback( function ( value ) {
    var calc = ( 42 / value ) % 2;

    return calc ? true : calc;
  } );

  expect( validate( 3, assert ) ).not.to.be( true );
  expect( validate( 3, assert ).show() ).to.eql( { assert: 'Callback', value: 3, violation: { result: 0 } } );
  expect( validate( 42, assert ) ).to.be( true );

  // improved Callback
  assert = is.callback( function ( value, string1, string2 ) {
    return value + string1 + string2 === 'foobarbaz';
  }, 'bar', 'baz' );
  expect( validate( 'foo', assert ) ).to.be( true );
  expect( validate( 'bar', assert ) ).to.be( false );
} )

A note on type checking

Note that Length assertion works for both String and Array type, so if you want to validate only strings, you should write an additional assertion:

validator.validate( 'foo', [
  is.ofLength( { min: 4, max: 100 } ),
  is.string()
] );

Extending

If you want to extend the library with your own asserts, you can use Assert.extend() which will return a copy of validator.Assert plus your custom asserts. This means that the original validator.Assert is always pristine.

Example:

var Assert = Validator.Assert;
var isExtended = Assert.extend({
  integer: Number.isInteger,
  NaN: Number.isNaN
});

expect( validate( 10, isExtended.integer() ).to.be( true );

Run Tests