El Validator
El Validator is a JSON Object validator and sanitizer. It's a great little tool for validating user input and sanitizing.
It's heavily inspired from the familiar Mongoose schema format with a few more features. (Note: El Validator doesn't attempt to strictly match the Mongoose validator)
- 0 dependencies
- Easy to use
- Lightweight (8.51Kb minified)
Installation
$ npm install elvalidator --saveOr in the browser:
<script type="text/javascript" src="https://unpkg.com/elvalidator/elvalidator.min.js"></script>Usage
import ElValidator from 'elvalidator';
// Set up the validator object
//let validator = new ElValidator(schema, options);
let validator = new ElValidator({
name : { type: String, required:true, trim:true, minLength:3 },
age : { type: Number, required:true, integer:true, min:18, max:100 },
agreedTelemetry : { type: Boolean, default:false },
// Array example:
tags : [
{ type: String, minLength:3, lowercase:true, trim:true, match: /^[a-z0-9]+$/ }
],
// Object example:
settings : {
darkMode : { type: Boolean, default:false },
codeEditor : { type: String, required:false, default:'atom', enum:['atom', 'vstudio', 'notepad++'] },
}
}, {
// When disabled, the validator will go easy on the errors. (i.e. a number is provided instead of a string the number will be converted to a string instead of throwing an error)
strictMode : true,
// Throw error when an unknown field is present
throwUnkownFields : false,
// Validate everything and then show big error message (vs. throw error as soon as an issue is detected)
accumulateErrors : false,
// Whether to dismiss subschema objects when empty
dismissEmptyObjects : false
});
// Validate/Sanitize a data object
// If there's an error, it will be thrown. You can thus use a try ... catch block to process the errors.
var sanitizedData = await validator.validate({
name : 'Yassine',
age : 27,
tags : ['PROgrammer', 'javascript '],
settings : {
darkMode : false,
},
other : 'unknown field',
});
console.log(sanitizedData);
/*
Outputs:
{
name: 'Yassine',
age: 27,
agreedTelemetry: false,
tags: [ 'programmer', 'javascript' ],
settings: { darkMode: false, codeEditor: 'atom' }
}
*/Schema Reference
String
{
field : {
type : String,
name : "Field Name", // For cleaner error messages
required : false, // Is this a mandatory field?
default : '', // If provided, the required field is not considered
lowercase : false, // Force string to lower case
uppercase : false, // Force string to UPPER CASE
trim : false, // Trim text (remove whitespace at the start and end of the string)
minLength : 3, // Minimum length of the string
maxLength : 15, // Maximum length of the string
enum : ['hello', 'world'], // Array with valid values for this field
match : /^(hello|world)$/i, // String must match with this regex
validator : async (value) => { // Manually validate/sanitize the value
if(!value)
throw new Error('Invalid value');
return value;
},
}
}Number
{
field : {
type : Number,
name : "Field Name", // For cleaner error messages
required : false, // Is this a mandatory field?
default : 0, // If provided, the required field is not considered
integer : false, // Force number to be an integer
min : 3, // Minimum value of the number
max : 15, // Maximum value of the number
enum : [5, 7, 12], // Array with valid values for this field
validator : async (value) => { // Manually validate/sanitize the value
if(!value)
throw new Error('Invalid value');
return value;
},
}
}Boolean
{
field : {
type : Boolean,
name : "Field Name", // For cleaner error messages
required : false, // Is this a mandatory field?
default : false, // If provided, the required field is not considered
validator : async (value) => { // Manually validate/sanitize the value
if(!value)
throw new Error('Invalid value');
return value;
},
}
}Array
{
// With default options
field : [
{ type: String } // Define the schema for the values this array should allow, in this case it accepts strings
],
// OR with options
field : {
type : [
{ type: String } // Define the schema for the values this array should allow, in this case it accepts strings
],
name : "Field Name", // For cleaner error messages
required : false, // Is this a mandatory field?
default : [], // If provided, the required field is not considered
minEntries : 0, // Minimum number of entries this array can hold
maxEntries : 10, // Maximum number of entries this array can hold
uniqueValues: false, // Whether to filter out the values of the array to only return non-repeating values
validator : async (value) => { // Manually validate/sanitize the value
if(!value)
throw new Error('Invalid value');
return value;
},
}
}Object
This type allows you to accept Objects with arbitrary fields and no particular validation.
{
field : {
type : Object,
name : "Field Name", // For cleaner error messages
required : false, // Is this a mandatory field?
default : {}, // If provided, the required field is not considered
validator : async (value) => { // Manually validate/sanitize the value
if(!value)
throw new Error('Invalid value');
return value;
},
}
}Mixed
This type allows you to accept any type of input with no particular validation.
{
field : {
type : ElValidator.Types.Mixed,
name : "Field Name", // For cleaner error messages
required : false, // Is this a mandatory field?
default : null, // If provided, the required field is not considered
enum : [false, 5, 'auto'], // Array with valid values for this field
validator : async (value) => { // Manually validate/sanitize the value
if(!value)
throw new Error('Invalid value');
return value;
},
}
}Sub-Schema
{
field : {
subField1 : { type: String },
subField2 : { type: Number },
subField3 : {
type : { type: String }, // Here type is a sub-sub-field and accepts strings
subSubField2 : { type: Number },
},
}
}$or operator
{
field : {
$or : [ // You can define different possible types for this particular field using the $or operator
{ type: String, }, // field can either be a string,
{ type: Number, min:0, max:10}, // a number between 0 and 10
{ type: Number, min:100, max:1000, integer: true}, // or an integer between 100 and 1000
],
default : '',
required : true,
}
}Built Ins
A few validators are available to make your life easier.
{
url : ElValidator.Builtins.Url,
domainName : ElValidator.Builtins.DomainName,
email : ElValidator.Builtins.Email,
youtubeVideo : ElValidator.Builtins.YoutubeVideo,
vimeoVideo : ElValidator.Builtins.VimeoVideo,
}
// will validate for:
{
url : 'https://www.example.com/index.html?query=param',
domainName : 'www.example.com',
email : 'user@example.com',
youtubeVideo : 'https://www.youtube.com/watch?v=UNG7vNchvVQ',
vimeoVideo : 'https://vimeo.com/347119375',
}