MySendQueueEmail.php

<?php
require '../vendor/autoload.php';

use Aws\Sqs\SqsClient;
use Aws\Exception\AwsException;

date_default_timezone_set('Asia/Tokyo');

$client = new SqsClient([
    'region' => 'ap-northeast-1',
    'version' => '2012-11-05'
]);

$params = [
    'MessageAttributes' => [
        'from' => [
            'DataType' => 'String',
            'StringValue' => '<ADDRESS_FROM>'
        ],
        'to' => [
            'DataType' => 'String',
            'StringValue' => '<ADDRESS_TO>'
        ],
        'subject' => [
            'DataType' => 'String',
            'StringValue' => 'Test'
        ]
    ],
    'MessageBody' => "Hello World!!",
    'QueueUrl' => '<QUEUE_URL>'
];

try {
    $result = $client->sendMessage($params);
    var_dump($result);
} catch (AwsException $e) {
    error_log($e->getMessage());
}