Usage

Import the module and call validateEmail with an email string. The function returns a promise that resolves to a ValidateEmailResult object, providing both overall validity and detailed diagnostic information.

import validateEmail from "@valentech/validate-email";

async function runValidation() {
  const email = "[email protected]";
  const result = await validateEmail(email);

  if (result.valid) {
    console.log("Email is valid!", result.details);
  } else {
    console.error("Invalid email:", result.reason);
    if (result.suggestion) {
      console.info("Did you mean:", result.suggestion);
    }
  }
}

runValidation();

API

validateEmail(email: string): Promise

Returns: A promise that resolves to an object with the following structure:

| Property | Type | Description | | ---------- | -------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | valid | boolean | Indicates if the email passed all checks. | | reason | string | null | Error identifier when validation fails. Possible values include:• invalid_syntax• disposable_domain• dns_timeout• invalid_domain• dns_error• unknown_error | | suggestion | string | null | Provides a suggested correction if the domain appears mistyped. | | details | object | Detailed result of various validation checks: |

details structure

| Property | Type | Description | | ------------- | --------------- | --------------------------------------------------------------- | | syntax | boolean | Result of the basic email syntax check. | | disposable | boolean | Whether the email belongs to a disposable domain. | | mxRecords | boolean | Whether MX DNS records were found. | | aRecords | boolean | Whether A/AAAA DNS records were found. | | smtpHandshake | boolean | null | Outcome of the SMTP handshake test (if performed). | | smtpPort | number | null | The port on which the SMTP handshake succeeded (if applicable). |

Features

Syntax Verification

Uses a regular expression along with the validator package to ensure the email is correctly formatted.

Disposable Domain Filtering

Compares the email's domain against a list of known disposable domains.

DNS Verification

Uses Node's DNS promises to check for MX and A/AAAA records. If no MX records are found but A/AAAA records are available, an SMTP handshake is attempted.

SMTP Handshake

Performs multi-port SMTP handshakes (plaintext on ports 25, 587, 2525 and TLS on port 465) to check if the domain can accept emails.

Typo Correction

Leverages a SymSpell-based lookup to suggest corrections for common email provider typos.

Caching

Utilizes LRU caches for email validations and DNS lookups to optimize performance.