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SMTP

PHPMailer

Installation

Install PHPMailer via Composer:

Code
composer require phpmailer/phpmailer

Basic Configuration

Use environment variables for credentials:

Code
<?php
// Load from environment or config
$smtpHost = 'smtp.lettermint.co';
$smtpUsername = 'lettermint';
$smtpPassword = getenv('LETTERMINT_API_TOKEN'); // Your API token

Advanced Features

Multiple Recipients

Code
$mail->addAddress('user1@example.com');
$mail->addAddress('user2@example.com');
$mail->addCC('manager@yourdomain.com');
$mail->addBCC('archive@yourdomain.com');

Attachments

Code
$mail->addAttachment('/path/to/file.pdf');
$mail->addAttachment('/path/to/image.jpg', 'custom-name.jpg');

Custom Headers

Code
$mail->addCustomHeader('X-Custom-Header', 'Custom Value');
$mail->addCustomHeader('X-Priority', '1');

Lettermint Headers

Add Lettermint-specific headers for tags, metadata, and routing:

Code
// Tag for categorization
$mail->addCustomHeader('X-LM-Tag', 'order-confirmation');

// Metadata for tracking (included in webhooks)
$mail->addCustomHeader('X-LM-Metadata-order_id', '12345');
$mail->addCustomHeader('X-LM-Metadata-customer_id', 'cust_789');

// Route selection
$mail->addCustomHeader('X-Lettermint-Route', 'transactional');