详解PHP对接paypal支付

环境准备

注册paypal账号注册paypal开发者账号创建paypal沙盒测试账户创建paypal应用下载PHP SDK实现支付实现支付成功回调实现退款更多API代码模板

注册paypal账号

www.paypal.com 注册商家账户选择，”创建商家用户”，根据要求填写信息，注册完得去邮箱激活

注册paypal开发者账号

developer.paypal.com 使用上一步注册的账号登录在左侧导航栏点击Accounts，创建两个sandbox账号，一个个人账号（personal）用于付款，一个商家账号（business）用于收款，系统已经默认创建了两个，可以自己选择创建，方便记忆； 创建账号后记得给当前账号添加余额用于接下来的测试。
用刚才创建的测试账号登录沙盒测试站点，查看金额和交易信息www.sandbox.paypal.com

创建沙盒应用APP

账号默认给创建好了一个Default Application，点击查看获取 ClientId和Secret；保存起来，接下来接口调用会使用到；（上线时请重新创建一个Live的应用）

下载SDK

本人使用laravel框架，使用composer下载paypal包composer require paypal/rest-api-sdk-php

实现支付

以下是生成支付的代码片段，伪代码

function createPayPal(){
      $shippingPrice = 2;
      $taxPrice = 0;
      $subTotal = 26;
      $item1 = new PayPal\Api\Item();
      $item1->setName("产品2")->setCurrency("USD")->setQuantity(1)->setPrice(10);
      $item2 = new PayPal\Api\Item();
      $item2->setName("产品1")->setCurrency("USD")->setQuantity(2)->setPrice(8);

      $itemList = new PayPal\Api\ItemList();
      $itemList->addItems([$item1,$item2]);

      // Set payment details
      $details = new PayPal\Api\Details();
      $details->setShipping($shippingPrice)->setTax($taxPrice)->setSubtotal($subTotal);

      // Set payment amount
      //注意，此处的subtotal，必须是产品数*产品价格，所有值必须是正确的，否则会报错
      $total = $shippingPrice + $subTotal + $taxPrice;
      $amount = new PayPal\Api\Amount();
      $amount->setCurrency("USD")->setTotal($total)->setDetails($details);

      // Set transaction object
      $transaction = new PayPal\Api\Transaction();
      $transaction->setAmount($amount)->setItemList($itemList)->setDescription("这是交易描述")
          ->setInvoiceNumber(uniqid());//setInvoiceNumber为支付唯一标识符,在使用时建议改成订单号

      $payer = new PayPal\Api\Payer();
      $payer->setPaymentMethod('paypal');//["credit_card", "paypal"]
      $redirectUrls = new PayPal\Api\RedirectUrls();
      $redirectUrl = "http://test.com/redirect/success";//支付成功跳转的回调
      $cancelUrl = "http://test.com/redirect/cancel";//取消支付的回调
      $redirectUrls->setReturnUrl($redirectUrl)->setCancelUrl($cancelUrl);

      // Create the full payment object
      $payment = new PayPal\Api\Payment();
      $payment->setIntent("sale")->setPayer($payer)->setRedirectUrls($redirectUrls)->addTransaction($transaction);

      try {
          $clientId = "xxxxxx";//上面应用的clientId和secret
          $secret = "XXXXXX";
          $oAuth = new \PayPal\Auth\OAuthTokenCredential($clientId, $secret);
          $apiContext =  new \PayPal\Rest\ApiContext($oAuth);
          if(env('APP_DEBUG') === false ){
              $apiContext->setConfig(['mode' => 'live']);//设置线上环境,默认是sandbox
          }
          $payment->create($apiContext);
          $approvalUrl = $payment->getApprovalLink();
          dd($approvalUrl);//这个是请求支付的链接，在浏览器中请求此链接就会跳转到支付页面
      } catch (\Exception $e) {
          dd($e->getMessage());//错误提示
      }
  }

以下是支付成功的回调代码片段，伪代码

function payRedirect(Request $request)
  {
      $paymentID = $request->get('paymentId');
      $payerId = $request->get('PayerID');

      $clientId = "xxxxxx";//上面应用的clientId和secret
      $secret = "XXXXXX";
      $oAuth = new \PayPal\Auth\OAuthTokenCredential($clientId, $secret);
      $apiContext =  new \PayPal\Rest\ApiContext($oAuth);       
      if(env('APP_DEBUG') === false ){
          $apiContext->setConfig(['mode' => 'live']);//设置线上环境,默认是sandbox
      }
      $payment = \PayPal\Api\Payment::get($paymentID, $apiContext);

      $execute = new \PayPal\Api\PaymentExecution();
      $execute->setPayerId($payerId);

      try{
          $payment = $payment->execute($execute, $apiContext);//执行,从paypal获取支付结果
          $paymentState = $payment->getState();//Possible values: created, approved, failed.
          $invoiceNum = $payment->getTransactions()[0]->getInvoiceNumber();
          $payNum = $payment->getTransactions()[0]->getRelatedResources()[0]->getSale()->getId();//这是支付的流水单号，必须保存，在退款时会使用到
          $total = $payment->getTransactions()[0]->getRelatedResources()[0]->getSale()->getAmount()->getTotal();//支付总金额
          $transactionState = $payment->getTransactions()[0]->getRelatedResources()[0]->getSale()->getState();//Possible values: completed, partially_refunded, pending, refunded, denied.

          if($paymentState == 'approved' && $transactionState == 'completed'){
              //处理成功的逻辑，例如：判断支付金额与订单金额，更新订单状态等
              return "success";//返回成功标识
          }else{
              //paypal回调错误,paypal状态不正确
              return "error";//返回错误标识
          }
      }catch(\Exception $e){
          dd($e->getMessage());
      }
  }

退款

退款必须要有支付成功的流水单号

一个流水单号可以进行多次退款

退款成功之后，在账号的交易记录中不体现，测试时请登录测试账号自己记录一下余额的变化情况，以确定退款是否成功

商家账号会减少余额并增加手续费（手续费是之前付款多收的），用户账号会增加余额

function refundOrder()
  {
      try{
          $refundRequest = new \PayPal\Api\RefundRequest();
          $amount = new \PayPal\Api\Amount();
          $amount->setCurrency("USD")->setTotal(10);//退总金额
          $refundRequest->setAmount($amount);
          $refundRequest->setDescription("退款测试");
          $sale = new \PayPal\Api\Sale();
          $sale->setId("XXXXXXXXX");//支付单号,支付成功时保存的支付流水单号
          $clientId = "xxxxxx";//上面应用的clientId和secret
          $secret = "XXXXXX";
          $oAuth = new \PayPal\Auth\OAuthTokenCredential($clientId, $secret);
          $apiContext =  new \PayPal\Rest\ApiContext($oAuth);
          if(env('APP_DEBUG') === false ){
              $apiContext->setConfig(['mode' => 'live']);//设置线上环境,默认是sandbox
          }
          $detailedRefund = $sale->refundSale($refundRequest, $apiContext);//调接口
          $refundState = $detailedRefund->getState();//Possible values: pending, completed, cancelled, failed.

          //var_dump($refundedSale);
          if($refundState == 'completed'){
              //退款成功,返回
          }else{
              dd('paypal 退款失败, 状态不正确');
          }
      }catch (\Exception $exception){
          dd($exception->getMessage());//发生异常
      }
  }

更多接口代码示例

http://paypal.github.io/PayPal-PHP-SDK/sample/

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