使用Greenfield API/PHP整合BTCPay Server：发票创建后无法跳转结账链接

我正尝试将BTCPay Server整合到自身网站中，本人为PHP新手。目前发票创建功能可正常运行，但用户点击比特币支付后，成功生成新发票却无法跳转至结账链接。我使用官方Greenfield PHP库辅助整合。

我的create_invoice.php代码 #

session_start();

// Include autoload file.
require __DIR__ . '/../vendor/autoload.php';

// Import Invoice client class.
use BTCPayServer\Client\Invoice;
use BTCPayServer\Client\InvoiceCheckoutOptions;
use BTCPayServer\Util\PreciseNumber;

// Fill in with your BTCPay Server data.
$apiKey = 'aaaaaaaaaa';
$host = 'https://aa.demo.btcpayserver.org/';
$storeId = 'aaaaaa';
$amount = $_POST['amount'];
$currency = 'USD';
$orderId = $_SESSION['name']."#" . mt_rand(0, 1000);
$buyerEmail = $_SESSION['name'];

try {
    $client = new Invoice($host, $apiKey);
    var_dump(
        $client->createInvoice(
            $storeId,
            $currency,
            PreciseNumber::parseString($amount),
            $orderId,
            $buyerEmail
        )
    );
} catch (\Throwable $e) {
    echo "Error: " . $e->getMessage();
}

表单提交后返回的Invoice对象（已替换敏感信息） #

object(BTCPayServer\Result\Invoice)#6 (1) 
{ 
  ["data":"BTCPayServer\Result\AbstractResult":private] => array(16) 
  { 
    ["id"]=> string(22) "aaaaaaaaaaa" 
    ["storeId"]=> string(44) "ssssssssssssssssssssssssssss" 
    ["amount"]=> string(4) "18.0" 
    ["checkoutLink"]=> string(62) "https://demo.aa.btcpayserver.org/i/aaaaaaaaaaaaaa" 
    ["status"]=> string(3) "New" 
    ["additionalStatus"]=> string(4) "None" 
    ["monitoringExpiration"]=> int(1669087659) 
    ["expirationTime"]=> int(1669080459) 
    ["createdTime"]=> int(1669078659) 
    ["availableStatusesForManualMarking"]=> array(2) 
    { 
      [0]=> string(7) "Settled" 
      [1]=> string(7) "Invalid" 
    } 
    ["archived"]=> bool(false) 
    ["type"]=> string(8) "Standard" 
    ["currency"]=> string(3) "USD" 
    ["metadata"]=> array(1) 
    { 
      ["orderId"]=> string(4) "#501" 
    } 
    ["checkout"]=> array(10) { 
      ["speedPolicy"]=> string(9) "HighSpeed" 
      ["paymentMethods"]=> array(1) 
      { 
        [0]=> string(3) "BTC" 
      } 
      ["defaultPaymentMethod"]=> NULL 
      ["expirationMinutes"]=> int(30) 
      ["monitoringMinutes"]=> int(120) 
      ["paymentTolerance"]=> float(0) 
      ["requiresRefundEmail"]=> NULL 
      ["defaultLanguage"]=> NULL 
    } 
    ["receipt"]=> array(3) 
    { 
      ["enabled"]=> NULL 
      ["showQR"]=> NULL 
      ["showPayments"]=> NULL 
    } 
  } 
} 

我的需求是在发票创建后跳转至该checkoutLink，但尝试以下代码时出现错误：Error: Cannot access offset of type string on string

if ($response->getStatus() === 200) {
        $data1 = $response->getBody();
        $link1 = $data1["checkoutLink"];
        echo $link1;
        
    } else {
        throw $this->getExceptionByStatusCode($method, $url, $response);
    }

解决方案 #

错误原因 #

你尝试的代码是针对原始HTTP响应的处理逻辑，但Greenfield PHP库已经将API响应自动解析成了BTCPayServer\Result\Invoice对象，不需要再手动处理getStatus()或getBody()。getBody()返回的是字符串格式的响应内容，不是数组，所以用数组方式访问会触发偏移量错误。

修改后的代码 #

直接从返回的Invoice对象中获取结账链接并跳转：

session_start();

require __DIR__ . '/../vendor/autoload.php';

use BTCPayServer\Client\Invoice;
use BTCPayServer\Util\PreciseNumber;

$apiKey = 'aaaaaaaaaa';
$host = 'https://aa.demo.btcpayserver.org/';
$storeId = 'aaaaaa';
$amount = $_POST['amount'];
$currency = 'USD';
$orderId = $_SESSION['name']."#" . mt_rand(0, 1000);
$buyerEmail = $_SESSION['name'];

try {
    $client = new Invoice($host, $apiKey);
    // 保存生成的Invoice对象
    $invoice = $client->createInvoice(
        $storeId,
        $currency,
        PreciseNumber::parseString($amount),
        $orderId,
        $buyerEmail
    );
    
    // 两种方式获取结账链接二选一
    $checkoutLink = $invoice['checkoutLink'];
    // 或者使用getter方法：$checkoutLink = $invoice->getCheckoutLink();
    
    // 跳转至BTCPay结账页面
    header("Location: " . $checkoutLink);
    exit; // 跳转后必须终止脚本执行，避免后续代码运行
} catch (\Throwable $e) {
    echo "Error: " . $e->getMessage();
}

内容的提问来源于stack exchange，提问作者mike_11