最近在業務場景裏有接收解析用户主動發送的郵件，使用php-imap實現了這一需求，記錄一下。

確定實現方式

讀取郵件的協議有POP3和IMAP兩種，區別：POP3協議允許電子郵件客户端下載服務器上的郵件，但是在客户端的操作，不會反饋到服務器上。IMAP提供webmail與電子郵件客户端之間的雙向通信，客户端的操作都會反饋到服務器上，對郵件進行的操作，服務器上的郵件也會做相應的動作。

需求要求處理完用户的郵件以後，將郵件標記為已處理，因此選用IMAP協議。

安裝依賴

本地、服務器php均需要安裝imap擴展。在項目的composer.json中添加php-imap擴展如下：

"require": {
  "php-imap/php-imap": "^3.1",
},

配置相關服務

namespace app\library\service\mail;

use PhpImap\Exceptions\ConnectionException;
use PhpImap\Mailbox;

/**
 * 收郵件服務郵件API接口
 * Class PlayService
 * @package app\library\service
 */
class ImapService
{
    public $path = '{imap.263.net:993/imap/ssl}INBOX';   // IMAP server and mailbox folder
    public $login = 'user@263.cn';         // Username for the before configured mailbox
    public $password = 'pwd';                   // Password for the before configured username
    public $dir = null;        // Directory, where attachments will be saved (optional)
    public $encoding = 'UTF-8';   // Server encoding (optional)

    public $mailbox;

    public function __construct()
    {
        $this->mailbox = new Mailbox(
            $this->path,
            $this->login,
            $this->password,
            $this->dir,
            $this->encoding
        );
    }

獲取所有未讀郵件列表

public function unSeenList()
{
    try {
        $mail_ids = $this->mailbox->searchMailbox('UNSEEN');
    } catch (ConnectionException $ex) {
        die('IMAP connection failed: ' . $ex->getMessage());
    } catch (\Exception $ex) {
        die('An error occured: ' . $ex->getMessage());
    }

    // If $mailsIds is empty, no emails could be found
    if (!$mail_ids) {
        die('Mailbox is empty');
    }

    try {
        $info = $this->mailbox->getMailsInfo($mail_ids);
    } catch (ConnectionException $ex) {
        echo "IMAP connection failed: " . $ex;
        die();
    }
    return ['ids' => $mail_ids, 'list' => $info];
}

將某些郵件標記為已讀

/**
 * @param array $mail_ids
 * @return mixed
 */
public function markRead($mail_ids)
{
    return $this->mailbox->markMailsAsRead($mail_ids);
}

搜索指定主題的郵件並標記為已讀

$imap = new ImapService();
$condition = 'UNSEEN  SUBJECT "' . $title . '" SINCE "' . date('Y-m-d', strtotime('-1 days')) . '" FROM ' . $mail;
$data['mail'] = $imap->mailbox->searchMailbox($condition);
if (!empty($data['mail'])) {
    $data['info'] = $imap->mailbox->getMailsInfo($data['mail']);
    if ($params['mark'] == 1) {
        $data['mark'] = $imap->markRead(array_column($data['info'], 'uid'));
    }
}