Have ideas to improve npm?Join in the discussion! »

TypeScript icon, indicating that this package has built-in type declarations

0.1.6 • Public • Published


Simple Friendly Node.js Validator.


npm install sfn-validator --save


This package supports any version of Node.js that higher than 4.0.0.


const Validator = require("sfn-validator");
var validator = new Validator({
    name: {
        type: "string",
        required: true,
        length: [3, 18]
    email: {
        type: "email",
        required: true,
        strict: true,
    password: {
        type: "string",
        required: true,
        length: [8, 18],
        msg: {
            required: "You must provide a 'password' in this form.",
            equals: "The length of the 'password' must between 8 and 18.",
    check_password: {
        type: "string",
        required: true,
        equals: "password",
    url: "url" // Short-hand, equal to {type: "url"}.


  • new Validator(rules: any) Creates a validator with specified rules.
  • validator.validate(data: any) Checks if the input data are all valid.
    • alias: validator.check()
  • validator.filter(data: any): any Filters input data according to the rules.


Every field of rule can be defined with these properties:

  • type The data type to check, could be:
    • string
    • number
    • boolean
    • object Carries children fields.
    • array
    • email
    • url
    • date Date instance or a valid date string.
    • time Unix timestamp or time string.
    • color Color name, hex, RGB, RGBA color string.
    • ipv4
    • ipv6
    • mac Media Access Control address (Machine address).
    • uuid Universal Unique Identifier.
    • isbn International Standard Book Number.
    • ascii Only contains ASCII characters.
    • base64 Only contains base64 characters.
    • json
    • data-uri
  • required Whether the field is required (true) or not (false, default).
  • equals The value of this field should be equal to the given field's.
  • msg Customize error messages, could be a string that sets all messages, or an object sets messages for type, required and equals. If the field has a length or range property, their error messages could be set as well.
  • length Only for string, email, url, ascii, base64, json, data-uri and array, could be a number sets an exact length, or an array sets the minimum and maximum length.
  • range Only for number, an array set the range (minimum and maximum) of the data value.
  • strict Strict mode, only for number, boolean, email, url, ipv4, isbn, it's false by default for most types except number, which is true by default.
  • children Only for object, to set children rules.

More Details About Strict Mode

  • number When non-strict, treat numeric string as number.
  • email If strict, the email address can only contain ASCII characters, and the hostname must not be localhost.
  • url If strict, the hostname can only contain ASCII characters, and the hostname must not be localhost.
  • ipv4 If strict, reject private and reserved IP addresses.
  • isbn If strict, the book number must be prettified with hyphenates (-).

Pre-check of Rule Definition

When you call new Validator() and pass the rules, the program will perform checking on the rules you provided, if any of them is invalid, an error will be thrown and tells you where is incorrect in your rules, so that you can find and fix it as soon as possible.

What Will Happen If Validating Failed?

If validating failed, validator.validate() will thrown an error message. You can catch the error with a try...catch... block. This package will modify the initial error stack and only shows you the useful parts, so it's very friendly on user-experience.

About Children Rule

If you specify a field's type object, then this field can and must carry children fields, like this example:

var rules = {
    multi: {
        type: "object",
        children: {
            name: "string",
            email: "email"
// And input data should like this:
var data = {
    multi: {
        name: "John",
        email: "john@example.com"

Children rules can be nested and unlimited, BUT, if you use equals property, be aware that it can only refers to the same depth of the rule.


npm i sfn-validator

DownloadsWeekly Downloads






Unpacked Size

155 kB

Total Files


Last publish


  • avatar