This script shows how to use the MailChimp v3 API to re-subscribe a large group of mistakingly unsubscribed email addresses in a MailChimp List. There are a couple examples commented out that can be used. The first shows how to look up the status of a batch API call sent to MailChimp. And the second shows how to make a batch API call to re-subsc…

mailchimp-v3-batch-updates.php

<?php

// replace this with your mailchimp api key
$mailchimp_apikey = "mailchimp-api-key-goes-here";

// create mailchimp api object that is used later to make api calls
$mcapi = new MailChimp_API($mailchimp_apikey);

/**
// Use the following code if you want to look up the status of a batch call

// array of batch ids provide after sending batch calls to mailchimp
$batch_ids = array(
  '1478dc8420',
  'a2f8edac18',
  '4b46167342',
  '9c22a6f907',
  'c5750659c3',
  '4de8cc1017',
  '6af75c9a83',
  'badb3f6ad7',
);

foreach ($batch_ids as $batch_id)
{
	$response = $mcapi->get_batches($batch_id);
	var_dump($response);
	echo "<hr>";
}

exit;
*/

/**
// Use the following code if you want to mass update subsribers in MailChimp
// The example below 'subscribes' people to the MailChimp list even if they have already unsubscribed
// This helps if there is an accidental mass unsubscribe

// the array of email addresses you want to update
$emails = array(
	"email1@website.com",
	"email2@website.com",
	"email3@website.com",
	"email4@website.com",
	"email5@website.com",
	"email6@website.com",
	"email7@website.com",
	"email8@website.com",
);

// the mailchimp list id you want to update the emails on
$list_id = 'd0ffa58810';

// the size of the batch calls you send at one time
$batch_size = 200;

$subscribers = array();
$num_emails = count($emails);

for ($i=1;$i<=$num_emails;$i++)
{
	// you can set whatever data you want here to update in MailChimp
	$subscribers []= array(
		'id' => uniqid(),
		'email_address' => $emails[($i-1)],
		'status' => 'subscribed',
	);

	if ($i%$batch_size == 0)
	{
		// send the batch data every one hundred calls
		$response = $mcapi->update_subscribers($list_id,$subscribers);

		// print the response
		var_dump($response);

		// empty the subscriber array
		$subscribers = array();
	}
}

// for loop ended, process the final group
$response = $mcapi->update_subscribers($list_id,$subscribers);
var_dump($response);

*/





// helper class to talk with MailChimp v3 batch API
class MailChimp_API 
{
	private $apikey = false;

	function __construct($apikey=false)
	{
		if (!empty($apikey))
		{
			$this->apikey = $apikey;
		}
	}

	public function update_subscribers($list_id,$subscribers)
	{
		if (empty($list_id))
		{
			$GLOBALS['log']->warning('MailChimp_API update_subscribers: list_id is empty');
			return false;
		}

		if (empty($subscribers) or !is_array($subscribers))
		{
			$GLOBALS['log']->warning('MailChimp_API update_subscribers: subscribers is empty or not an array');
			return false;
		}

		$operations = array();
		$type = "PUT";
		$url = "lists/{$list_id}/members/";

		foreach ($subscribers as $key => $subscriber)
		{
			if (empty($subscriber['id']))
			{
				// id is required
				$GLOBALS['log']->warning('MailChimp_API update_subscribers: no id for subscriber '.print_r($subscriber,true));
				continue;
			}

			if (empty($subscriber['email_address']))
			{
				// email address required
				$GLOBALS['log']->warning('MailChimp_API update_subscribers: no email_address for subscriber '.print_r($subscriber,true));
				continue;
			}

			$email_hash = $this->get_email_hash($subscriber['email_address']);
			$path = $url . $email_hash;

			$operations []= array(
				"method" => $type,
				"path" => $path,
				"operation_id" => $subscriber['id'],
				"body" => json_encode($subscriber),
			);
		}

		return $this->post_batches($operations);
	}

	public function post_batches($operations)
	{
		if (empty($operations) or !is_array($operations))
		{
			return false;
		}

		$type = "POST";
		$url = "batches";
		$data = array(
			"operations" => $operations
		);

		return $this->call_API($type,$url,$data);
	}

	public function get_batches($batch_id)
	{
		if (empty($batch_id))
		{
			return false;
		}

		$type = "GET";
		$url = "batches/{$batch_id}";

		return $this->call_API($type,$url);
	}

	public function get_email_hash($email)
	{
		if (empty($email))
		{
			$GLOBALS['log']->warning('MailChimp_API get_email_hash: no email provided');
			return false;
		}

		return md5(strtolower($email));
	}

	// the base API url is auto populated
	// assuming json is being used goint to MC and returned from them
	// $ext is used to set the extension
	// example: call_API('POST', 'lists/'
	public function call_API($request_type, $ext='', $body='')
	{
		/** 
		// If using in a system where SugarChimp is installed
		// You can use the following line to get the customers MailChimp apikey

		$apikey = SugarChimp_Setting::retrieve('apikey');

		// otherwise grab it from somewhere else
		*/

		$apikey = $this->apikey;

		$split = explode('-',$apikey);
		$dc = $split[1];
		$url = $dc . '.api.mailchimp.com/3.0/' . $ext;
		$curl = curl_init();
		$opts = array(
			CURLOPT_HTTPHEADER => array('Authorization: apikey ' . $apikey),
		    CURLOPT_URL => $url,
		    CURLOPT_RETURNTRANSFER => true,
		    CURLOPT_CUSTOMREQUEST => $request_type
	    );

		switch ($request_type)
        {
            case 'POST':
            case 'DELETE':
			    $opts[CURLOPT_POST] = 1;
			    $opts[CURLOPT_POSTFIELDS] = json_encode($body);
		    break;
		    case 'PUT':
			    $opts[CURLOPT_POSTFIELDS] = json_encode($body);
		    break;
		}
		
		curl_setopt_array($curl, $opts);
		$result = curl_exec($curl);
		curl_close($curl);

		return json_decode($result);
	}
}