File: //usr/lib/node_modules/forever/node_modules/revalidator/README.md
# revalidator [](http://travis-ci.org/flatiron/revalidator)
A cross-browser / node.js validator used by resourceful and flatiron. Revalidator has [JSONSchema](http://tools.ietf.org/html/draft-zyp-json-schema-04) compatibility as primary goal.
## Example
The core of `revalidator` is simple and succinct: `revalidator.validate(obj, schema)`:
``` js
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.
``` js
{
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`.
## Installation
### Installing npm (node package manager)
``` bash
$ curl http://npmjs.org/install.sh | sh
```
### Installing revalidator
``` bash
$ [sudo] npm install revalidator
```
## Usage
`revalidator` takes json-schema as input to validate objects.
### revalidator.validate (obj, schema, options)
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.
``` js
{
valid: true // or false
errors: [/* Array of errors if valid is false */]
}
```
#### Available Options
* __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_)
* __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.
### Schema
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
#### required
If true, the value should not be undefined
```js
{ required: true }
```
#### allowEmpty
If false, the value must not be an empty string
```js
{ allowEmpty: false }
```
#### type
The `type of value` should be equal to the expected value
```js
{ type: 'string' }
{ type: 'number' }
{ type: 'integer' }
{ type: 'array' }
{ type: 'boolean' }
{ type: 'object' }
{ type: 'null' }
{ type: 'any' }
{ type: ['boolean', 'string'] }
```
#### pattern
The expected value regex needs to be satisfied by the value
```js
{ pattern: /^[a-z]+$/ }
```
#### maxLength
The length of value must be greater than or equal to expected value
```js
{ maxLength: 8 }
```
#### minLength
The length of value must be lesser than or equal to expected value
```js
{ minLength: 8 }
```
#### minimum
Value must be greater than or equal to the expected value
```js
{ minimum: 10 }
```
#### maximum
Value must be lesser than or equal to the expected value
```js
{ maximum: 10 }
```
#### allowEmpty
Value may not be empty
```js
{ allowEmpty: false }
```
#### exclusiveMinimum
Value must be greater than expected value
```js
{ exclusiveMinimum: 9 }
```
### exclusiveMaximum
Value must be lesser than expected value
```js
{ exclusiveMaximum: 11 }
```
#### divisibleBy
Value must be divisible by expected value
```js
{ divisibleBy: 5 }
{ divisibleBy: 0.5 }
```
#### minItems
Value must contain more then expected value number of items
```js
{ minItems: 2 }
```
#### maxItems
Value must contains less then expected value number of items
```js
{ maxItems: 5 }
```
#### uniqueItems
Value must hold a unique set of values
```js
{ uniqueItems: true }
```
#### enum
Value must be present in the array of expected value
```js
{ enum: ['month', 'year'] }
```
#### format
Value must be a valid format
```js
{ 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' }
```
#### conform
Value must conform to constraint denoted by expected value
```js
{ conform: function (v) {
if (v%3==1) return true;
return false;
}
}
```
#### dependencies
Value is valid only if the dependent value is valid
```js
{
town: { required: true, dependencies: 'country' },
country: { maxLength: 3, required: true }
}
```
### Nested Schema
We also allow nested schema
```js
{
properties: {
title: {
type: 'string',
maxLength: 140,
required: true
},
author: {
type: 'object',
required: true,
properties: {
name: {
type: 'string',
required: true
},
email: {
type: 'string',
format: 'email'
}
}
}
}
}
```
### Custom Messages
We also allow custom message for different constraints
```js
{
type: 'string',
format: 'url'
messages: {
type: 'Not a string type',
format: 'Expected format is a url'
}
```
```js
{
conform: function () { ... },
message: 'This can be used as a global message'
}
```
## Tests
All tests are written with [vows][0] and should be run with [npm][1]:
``` bash
$ npm test
```
#### Author: [Charlie Robbins](http://nodejitsu.com), [Alexis Sellier](http://cloudhead.io)
#### Contributors: [Fedor Indutny](http://github.com/indutny), [Bradley Meck](http://github.com/bmeck), [Laurie Harper](http://laurie.holoweb.net/)
#### License: Apache 2.0
[0]: http://vowsjs.org
[1]: http://npmjs.org