建站之阿里云邮件推送

评论被回复时，如果评论者填了邮箱，则向其发送通知邮件。使用阿里云的邮件推送。每日免费额度 200 封。

/**
 * 发送阿里云邮件
 */
class Util_Mail
{
    private static $url, $accessId, $accessSecret, $account, $name;

    public static function send($title, $content, $receiver = null)
    {
        if (empty($title) || empty($content)) {
            return false;
        }

        self::init();

        if (is_null($receiver)) {
            $receiver = Common::getAdminMail();
        } elseif (!filter_var($receiver, FILTER_VALIDATE_EMAIL)) {
            return false;
        }

        //计算签名
        $encode = function ($string) {
            return str_replace(['+', '*', '%7E'], ['%20', '%2A', '~'], urlencode($string));
        };

        //阿里云dm
        $data = [
            'Format'           => 'JSON',
            'Version'          => '2015-11-23',
            'AccessKeyId'      => self::$accessId,
            'SignatureMethod'  => 'HMAC-SHA1',
            'Timestamp'        => date('Y-m-d\TH:i:s\Z', time() - date('Z')), //utc 时间
            'SignatureVersion' => '1.0',
            'SignatureNonce'   => uniqid(),
            'Action'           => 'SingleSendMail',
            'AccountName'      => self::$account,
            'ReplyToAddress'   => 'false',
            'AddressType'      => 0,
            'ToAddress'        => $receiver,
            'FromAlias'        => self::$name,
            'Subject'          => $title,
            'HtmlBody'         => $content,
        ];

        ksort($data);
        $signature = '';
        foreach ($data as $k => $v) {
            $signature .= '&' . $encode($k) . '=' . $encode($v);
        }

        $signature = 'POST&%2F&' . $encode(substr($signature, 1));

        $data['Signature'] = base64_encode(hash_hmac('sha1', $signature, self::$accessSecret . '&', true));

        $ch = curl_init();
        curl_setopt($ch, CURLOPT_URL, self::$url);
        curl_setopt($ch, CURLOPT_TIMEOUT, 60);
        curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, 60);
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
        curl_setopt($ch, CURLOPT_POST, 1);
        curl_setopt($ch, CURLOPT_POSTFIELDS, $data);
        curl_exec($ch);
    }

    private static function init()
    {
        if (empty(self::$url)) {
            $config = Yaf\Application::app()->getConfig()->get('dm');
            self::$url = $config->get('url');
            self::$accessId = $config->get('access_id');
            self::$accessSecret = $config->get('access_secret');
            self::$account = $config->get('account');
            self::$name = $config->get('name');
        }
    }
}