PHP PayPal /v2/checkout/orders/$paymentId/capture Restful API 返回 400 Bad Request 错误

如何解决PHP PayPal /v2/checkout/orders/$paymentId/capture Restful API 返回 400 Bad Request 错误

我正在开发一个使用 React.js 作为前端、PHP 作为后端 API 构建的项目。并在我的本地电脑上运行。 我尝试使用 PayPal Checkout order API 在 PHP 中创建订单。但是在PayPal中批准订单后，当我调用capture API完成订单时，它返回400 Bad Request: invalid method错误。这是创建订单的代码：

    $params = [
        'intent' => 'CAPTURE','purchase_units' => [
            [
                'amount' => [
                    'currency_code' => $currency,'value' => (string) $amount
                ],]
        ],'application_context' => [
            'user_action' => 'PAY_NOW','shipping_preference' => 'NO_SHIPPING','return_url' => $backUrl,'cancel_url' => $backUrl
        ],];

    $data = $this->encodeData($params);
    $headers = $this->getAuthHeaders($data);
    $res = $this->execute(self::POST,'/v2/checkout/orders/',$data,$headers);

    return $res;

这里是来自 GET /v2/checkout/order API 的订单详情响应：

  {
    id: "8D111388A5835981G",intent: "CAPTURE",status: "APPROVED",purchase_units: [
      {
        reference_id: "default",amount: { currency_code: "USD",value: "500.00" },payee: { email_address: "[e-mail]",merchant_id: "XXXXXXXXXXX" },},],payer: {
      name: { given_name: "John",surname: "Doe" },email_address: "[e-mail]",payer_id: "XXXXXXXX",address: { country_code: "US" },create_time: "2021-05-12T21:59:37Z",links: [
      { href: "https://api.sandbox.paypal.com/v2/checkout/orders/8D111388A5835981G",rel: "self",method: "GET" },{ href: "https://api.sandbox.paypal.com/v2/checkout/orders/8D111388A5835981G",rel: "update",method: "PATCH" },{
        href: "https://api.sandbox.paypal.com/v2/checkout/orders/8D111388A5835981G/capture",rel: "capture",method: "POST",};

正如可以详细看到的，此订单 APPROVED，因此我可以进行 capture API 调用。 但是当我这样做时，出现了 400 错误。这是捕获 API 调用：

$data = json_encode([]);
$headers = [
        "Content-Type: application/json",'Authorization: Bearer ' . $this->token,"Content-length: " . mb_strlen($data)
    ];

$res = $this->execute(self::POST,'/v2/checkout/orders/' . $paymentId . '/capture',$headers);

这里是执行函数：

private function execute(string $method,string $path,string $body,array $headers = [],$isNeedAuth = false)
{
    $this->requestParams = [
        'path' => $path,'body' => $body,'headers' => $headers
    ];
   
    curl_setopt($this->curl,CURLOPT_URL,$this->getUrl() . $path);
    curl_setopt($this->curl,CURLOPT_RETURNTRANSFER,true);
    curl_setopt($this->curl,CURLOPT_CUSTOMREQUEST,$method);

    if (empty($body) === false) {
        curl_setopt($this->curl,CURLOPT_POSTFIELDS,$body);
    }

    if (count($headers)) {
        curl_setopt($this->curl,CURLOPT_HTTPHEADER,$headers);
    }

    if ($isNeedAuth) {
        curl_setopt($this->curl,CURLOPT_HTTPAUTH,CURLAUTH_BASIC);
        curl_setopt($this->curl,CURLOPT_USERPWD,$this->clientId . ':' . $this->secret);
        
        $this->requestParams['keys'] = $this->clientId . ':' . $this->secret;
    }

    $res = curl_exec($this->curl);

    $this->response = $res;

    $resDecoded = $this->decodeData($res);

    return $resDecoded;
}

执行 curl 后，$res='400 Bad Request: invalid method'。

不确定原因，为什么不能完成订单，并出现错误。