isemail

What is isemail?

The isemail npm package is a module that allows you to validate email addresses according to the standards and specifications of the Internet Message Format and the DNS (Domain Name System). It is designed to ensure that email addresses are syntactically correct and can be used for sending and receiving emails.

What are isemail's main functionalities?

Email Validation

This feature allows you to validate whether a string is a valid email address. It returns a boolean indicating whether the email is valid or not.

const isEmail = require('isemail');
console.log(isEmail.validate('[e-mail]')); // true
console.log(isEmail.validate('invalid-email')); // false

Check DNS

This feature enables DNS checking as part of the validation process. It performs an asynchronous DNS lookup to see if the domain in the email address exists.

const isEmail = require('isemail');
isEmail.validate('[e-mail]', { checkDNS: true }, (err, isValid) => {
  console.log(isValid); // true or false based on DNS check
});

Error Level Reporting

This feature provides detailed error level reporting. Instead of a simple boolean, it returns a numeric error level indicating the type of validation error, if any.

const isEmail = require('isemail');
const result = isEmail.validate('[e-mail]', { errorLevel: true });
console.log(result); // 0 for valid email or a positive number representing the error level

Other packages similar to isemail

validator

Validator is a library of string validators and sanitizers. It provides a simple way to validate emails with the isEmail function, among many other validation functions. It is more comprehensive than isemail as it includes a wide range of validation and sanitization methods for different data types.

email-validator

Email-validator is a package specifically focused on email address validation. It offers a simple API with a single validate method. It is similar to isemail but does not provide DNS checking or detailed error level reporting.

README

isemail

Node email address validation library

Lead Maintainer: Eli Skeggs

This first version of isemail is a port of the PHP is_email function by Dominic Sayers.

Install

$ npm install isemail

Test

The tests were pulled from is_email's extensive test suite on October 15, 2013. Many thanks to the contributors! Additional tests have been added to increase code coverage and verify edge-cases.

Run any of the following.

$ lab
$ npm test
$ make test

remember to npm install!

API

isEmail(email, [options], [callback])

Determines whether the email is valid or not, for various definitions thereof. Optionally accepts an options object and a callback function. Options may include errorLevel and checkDNS. The callback function will always be called if specified, and the result of the operation supplied as the only parameter to the callback function. If isEmail is not asked to check for the existence of the domain (checkDNS), it will also synchronously return the result of the operation.

Use errorLevel to specify the type of result for isEmail. Passing a false literal will result in a true or false boolean indicating whether the email address is sufficiently defined for use in sending an email. Passing a true literal will result in a more granular numeric status, with zero being a perfectly valid email address. Passing a number will return 0 if the numeric status is below the errorLevel and the numeric status otherwise.

The tldWhitelist option can be either an object lookup table or an array of valid top-level domains. If the email address has a top-level domain that is not in the whitelist, the email will be marked as invalid.

The minDomainAtoms option is an optional positive integer that specifies the minimum number of domain atoms that must be included for the email address to be considered valid. Be careful with the option, as some top-level domains, like io, directly support email addresses. To better handle fringe cases like the io TLD, use the checkDNS parameter, which will only allow email addresses for domains which have an MX record.

Examples

$ node
> var isEmail = require('isemail');
undefined
> var log = console.log.bind(console, 'result');
undefined
> isEmail('[e-mail]');
true
> isEmail('[e-mail]', log);
result true
true
> isEmail('[e-mail]', {checkDNS: true});
undefined
> isEmail('[e-mail]', {checkDNS: true}, log);
undefined
result true
> isEmail('[e-mail]', {errorLevel: true});
0
> isEmail('[e-mail]', {errorLevel: true}, log);
result 0
0
> isEmail('[e-mail]');
true
> isEmail('[e-mail]', {checkDNS: true, errorLevel: true}, log);
undefined
result 6
> isEmail('[e-mail]', {checkDNS: true, errorLevel: 7}, log);
undefined
result 0
> isEmail('[e-mail]', {checkDNS: true, errorLevel: 6}, log);
undefined
result 6

TODO

Add tests for library usage, not just functionality comparisons. Future versions will improve upon the current version, optimizing it for efficient usage and DRYing the code.

License

BSD License