String validation and sanitization (validator.js) using promises

Usage no npm install needed!

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  import validatorAsPromised from '';


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Validator.js for Promises

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String validation (validator.js) and custom validators using promises


All standard validator.js methods are available.

Simply add the Async suffix to use the promise-based version. The first parameter is always the error message string which will be thrown as an error if the promise is rejected.

Method isAlphanumeric(value) becomes isAlphanumericAsync(errorMsg, value)


const validator = require('validator-as-promised');

// Synchronous method
if( validator.isAlphanumeric('abcdef') ) {
    console.log('String contains alphanumeric characters.');

// Asynchronous method (Promise)
validator.isAlphanumericAsync('String should contain alphanumeric characters!', 'abcdef').then((result) => {
}).catch((ex) => {

Custom Validators

You can define your own validation functions using the built-in .custom(errorMsg, func [, args...]) method:

// Example 1
validator.custom('Should be true!', (val) => { return val === true; }, true).then((result) => {
    console.log('Value is true!');
}).catch((ex) => {
    console.log('Value was not true!');

// Example 2
validator.custom('First number should be lower than second number!', (num1, num2) => { return num1 < num2; }, 34, 87).then((result) => {
    console.log('Validation succeeded!');
}).catch((ex) => {
    console.log('Validation failed!');

The custom function should return a truthy value or a promise. Synchronous functions will be promisified automatically.

Unlike validator.js methods which only accepts string inputs, the custom validators can accept values of any type.


$ npm test