email-validator-ultimate/dist/utils/format.js

Advanced email validation library for Node.js. RFC 5322 format validation, MX records, SMTP inbox check, disposable email detection, typo suggestions, risk analysis, Gravatar detection, DNS blacklist check, batch validation, caching, and CLI tool.

"use strict";
/**
 * RFC 5322 compliant email format validation
 * Validates email format with comprehensive checks
 */
Object.defineProperty(exports, "__esModule", { value: true });
exports.validateFormat = validateFormat;
exports.isValidFormat = isValidFormat;
exports.getFormatErrors = getFormatErrors;
// RFC 5322 compliant regex for email validation
const EMAIL_REGEX = /^(?:[a-z0-9!#$%&'*+/=?^_`{|}~-]+(?:\.[a-z0-9!#$%&'*+/=?^_`{|}~-]+)*|"(?:[\x01-\x08\x0b\x0c\x0e-\x1f\x21\x23-\x5b\x5d-\x7f]|\\[\x01-\x09\x0b\x0c\x0e-\x7f])*")@(?:(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\.)+[a-z0-9](?:[a-z0-9-]*[a-z0-9])?|\[(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?|[a-z0-9-]*[a-z0-9]:(?:[\x01-\x08\x0b\x0c\x0e-\x1f\x21-\x5a\x53-\x7f]|\\[\x01-\x09\x0b\x0c\x0e-\x7f])+)\])$/i;
// Maximum email length per RFC 5321
const MAX_EMAIL_LENGTH = 254;
const MAX_LOCAL_LENGTH = 64;
const MAX_DOMAIN_LENGTH = 253;
/**
 * Validates email format with detailed error reporting
 */
function validateFormat(email) {
    // Check for empty string
    if (!email || email.trim() === '') {
        return { isValid: false, error: 'Email address is empty' };
    }
    // Check total length
    if (email.length > MAX_EMAIL_LENGTH) {
        return { isValid: false, error: `Email exceeds maximum length of ${MAX_EMAIL_LENGTH} characters` };
    }
    // Check for @ symbol
    const atIndex = email.lastIndexOf('@');
    if (atIndex === -1) {
        return { isValid: false, error: 'Email must contain @ symbol' };
    }
    const localPart = email.substring(0, atIndex);
    const domainPart = email.substring(atIndex + 1);
    // Check local part length
    if (localPart.length === 0) {
        return { isValid: false, error: 'Local part (before @) is empty' };
    }
    if (localPart.length > MAX_LOCAL_LENGTH) {
        return { isValid: false, error: `Local part exceeds maximum length of ${MAX_LOCAL_LENGTH} characters` };
    }
    // Check domain part length
    if (domainPart.length === 0) {
        return { isValid: false, error: 'Domain part (after @) is empty' };
    }
    if (domainPart.length > MAX_DOMAIN_LENGTH) {
        return { isValid: false, error: `Domain exceeds maximum length of ${MAX_DOMAIN_LENGTH} characters` };
    }
    // Check for consecutive dots
    if (email.includes('..')) {
        return { isValid: false, error: 'Email cannot contain consecutive dots' };
    }
    // Check if local part starts or ends with dot
    if (localPart.startsWith('.') || localPart.endsWith('.')) {
        return { isValid: false, error: 'Local part cannot start or end with a dot' };
    }
    // Check if domain has at least one dot (TLD required)
    if (!domainPart.includes('.')) {
        return { isValid: false, error: 'Domain must have at least one dot' };
    }
    // Check TLD length (minimum 2 characters)
    const tld = domainPart.split('.').pop() || '';
    if (tld.length < 2) {
        return { isValid: false, error: 'TLD must be at least 2 characters' };
    }
    // Final RFC 5322 regex check
    if (!EMAIL_REGEX.test(email)) {
        return { isValid: false, error: 'Email format does not match RFC 5322 standard' };
    }
    return { isValid: true };
}
/**
 * Simple boolean check for email format validity
 * For backward compatibility
 */
function isValidFormat(email) {
    return validateFormat(email).isValid;
}
/**
 * Get detailed format validation errors
 */
function getFormatErrors(email) {
    const result = validateFormat(email);
    return result.error || null;
}