Upload Images to Ebay in parallel

ebay-upload-images-parallel.php

<?php

/**
the composer.json used here:
{
    "require": {
        "guzzlehttp/guzzle": "^6.3"
    },
    "require-dev": {
        "kint-php/kint": "^3.2"
    }
}
**/

use GuzzleHttp\Client;
use GuzzleHttp\Pool;

require 'vendor/autoload.php';

$client = new Client(['base_uri' => 'https://api.ebay.com/', 'debug' => true, 'exceptions' => false]);

$images[] = file_get_contents('/tmp2/img_data_main.png');
$images[] = file_get_contents('/tmp2/img_data_2.png');
$images[] = file_get_contents('/tmp2/img_data_3.png');

// sequential

/*foreach ($images as $ImageData) {

	$bla = $client->post('/ws/api.dll', [
		'headers'   => [
			'X-EBAY-API-APP-NAME'            => 'xxxxxxxxx',
			'X-EBAY-API-CERT-NAME'           => 'xxxxxxxxx',
			'X-EBAY-API-DEV-NAME'            => 'xxxxxxxxx',
			'X-EBAY-API-CALL-NAME'           => 'UploadSiteHostedPictures',
			'X-EBAY-API-COMPATIBILITY-LEVEL' => '1113',
			'X-EBAY-API-SITEID'              => '77',
		],
		'multipart' => [
			[
				'name'     => 'xml payload',
				'contents' => '<?xml version="1.0" encoding="utf-8"?>
<UploadSiteHostedPicturesRequest xmlns="urn:ebay:apis:eBLBaseComponents">
    <RequesterCredentials>
        <ebl:eBayAuthToken xmlns:ebl="urn:ebay:apis:eBLBaseComponents">xxxxxxxx</ebl:eBayAuthToken>
    </RequesterCredentials>
    <PictureName>something</PictureName>
    <PictureSet>Standard</PictureSet>
    <ExtensionInDays>1</ExtensionInDays>
</UploadSiteHostedPicturesRequest>',
			],
			[
				'name'     => 'image data',
				'filename' => 'something.png',
				'contents' => $ImageData
			]
		]
	]);
	d($bla->getBody()->getContents());
}
exit;*/

// parallel

$requests = function ($images) use ($client) {
	foreach ($images as $imageData) {
		yield function () use ($client, $imageData) {
			return $client->postAsync('/ws/api.dll', [
				'headers'   => [
					'X-EBAY-API-APP-NAME'            => 'xxxxxxxx',
					'X-EBAY-API-CERT-NAME'           => 'xxxxxxxx',
					'X-EBAY-API-DEV-NAME'            => 'xxxxxxxx',
					'X-EBAY-API-CALL-NAME'           => 'UploadSiteHostedPictures',
					'X-EBAY-API-COMPATIBILITY-LEVEL' => '1113',
					'X-EBAY-API-SITEID'              => '77',
				],
				'multipart' => [
					[
						'name'     => 'xml payload',
						'contents' => '<?xml version="1.0" encoding="utf-8"?>
<UploadSiteHostedPicturesRequest xmlns="urn:ebay:apis:eBLBaseComponents">
    <RequesterCredentials>
        <ebl:eBayAuthToken xmlns:ebl="urn:ebay:apis:eBLBaseComponents">xxxxxxxx</ebl:eBayAuthToken>
    </RequesterCredentials>
    <PictureName>something</PictureName>
    <PictureSet>Standard</PictureSet>
    <ExtensionInDays>1</ExtensionInDays>
</UploadSiteHostedPicturesRequest>',
					],
					[
						'name'     => 'image data',
						'filename' => 'something.png',
						'contents' => $imageData,
					]
				]
			]);
		};
	}
};

$pool = new Pool($client, $requests($images), [
	'concurrency' => 5,
	'fulfilled'   => function (GuzzleHttp\Psr7\Response $response, $index) {
		d($index, $response->getHeaders(),$response->getBody()->getContents());
	},
	'rejected'    => function ($reason, $index) {
		d($index, $reason);
	},
]);
// Initiate the transfers and create a promise
$promise = $pool->promise();
// Force the pool of requests to complete
$promise->wait();

d($pool);