IOS订阅优惠-PHP生成ECDSA算法签名

<?php
use ramsey\uuid\uuid;

class itunessignaturegenerator {
    private $appbundleid = 'www.u17.com';

    private $keyidentifier = 'zzzzzzz';

    private $itunesprivatekeypath = '/path/to/the/file.p8;

    /**
     * @see https://developer.apple.com/documentation/storekit/in-app_purchase/generating_a_signature_for_subscription_offers
     *
     * @param $productidentifier
     * @param $offeridentifier
     *
     * @return signature
     */
    public function generatesubscriptionoffersignature($productidentifier, $offeridentifier)
    {
        $nonce = strtolower(uuid::uuid1()->tostring());
        $timestamp = time() * 1000;
        $applicationusername = 'username';

        $message = implode(
            "\u{2063}",
            [
                $this->appbundleid,
                $this->keyidentifier,
                $productidentifier,
                $offeridentifier,
                $applicationusername,
                $nonce,
                $timestamp
            ]
        );

        $message = $this->sign($message);

        return new signature(
            base64_encode($message),
            $nonce,
            $timestamp,
            $this->keyidentifier
        );
    }

    private function sign($data)
    {
        $signature = '';

        openssl_sign(
            $data,
            $signature,
            openssl_get_privatekey('file://' . $this->itunesprivatekeypath),
            openssl_algo_sha256
        );

        return $signature;
    }
}

一些注意事项   openssl是可以直接进行ecdsa签名的

1、$nonce 必须为小写，并且每次购买时的nonce不能重复否则会报签名错误无法购买 code -12

2、$time   是毫秒time*1000

3、\u2063 的字符格式需要注意    php里面可以用户"\u{2063}" 来表示，但是有的一些环境不支持这样的写法 所以还可以使用另外一种  json_decode('"\u2036"')  来转一下格式