WeChat Pay-Server To Server Interaction Flow

Integration Navigation

Create Order and Pay

Use the Create Order and Pay interface to directly initiate WeChat Pay

Request Body Parametersapplication/json

Response Body Parametersapplication/json

Request Body Parametersapplication/json

Response Body Parametersapplication/json

Request Body Parametersapplication/json

Response Body Parametersapplication/json

QRCode

Android

iOS

Step2 Handle Payment Response

Handle returned payment parameters according to different payment scenarios:

Key Parameter Description:

1. device.orderTerminal

• 02-PC browser(pc)
• 04-SDK(ios)
• 05-SDK(Android)

2. shopperIP

• User's public IP address, required by WeChat Pay, otherwise will cause error
• Please obtain the real consumer IP address, cannot use localhost, 127.0.0.1 or other loopback addresses

Request Body Parametersapplication/json

Response Body Parametersapplication/json

Request Body Parametersapplication/json

Response Body Parametersapplication/json

Request Body Parametersapplication/json

Response Body Parametersapplication/json

QRCode

Android

iOS

PC Payment

device.orderTerminal = 02

Create order and pay interface return parameters:

• qrCode : WeChat's qrCode, merchant needs to handle QR code display
• paymentRedirectUrl : PingPongCheckout wrapped QR code page, just redirect to this page

Mobile Browser Payment

device.orderTerminal = 04 or 05

Create order and pay interface return parameters:

• paymentRedirectUrl : Corresponds to WeChat's mwebUrl parameter

Webview Payment

device.orderTerminal = 04 or 05

Create order and pay interface return parameters:

• paymentRedirectUrl : Corresponds to WeChat's mwebUrl parameter

Solution 1: Webview Directly Launch WeChat Pay

1. Request create order and pay interface, get paymentRedirectUrl.

2. Set Referer

   Android: Add Referer when loadUrl

   val headers = mutableMapOf<String, String>()
   headers["Referer"] = "https://your-domain.com"   // Must be consistent with authorized domain
   webView.loadUrl(mwebUrl, headers)

   iOS: Set Referer in request header (WKWebView)

   guard let url = URL(string: mwebUrl) else { return }
   var request = URLRequest(url: url)
   request.setValue("https://your-domain.com", forHTTPHeaderField: "Referer")
   webView.load(request)

3. Launch WeChat and pay

Solution 2: Launch WeChat Pay Through Intermediate Page

1. Request create order and pay interface, get paymentRedirectUrl.

2. Create pay-proxy intermediate page

   <!-- https://intermediate-page-domain/pay-proxy -->
   <script>
   (async () => {
     const { mweb_url } = await fetch('/api/getMwebUrl', {
       method: 'POST',
       body: JSON.stringify({ orderId: getQuery('orderId') })
     }).then(r => r.json());
   
     const redirect = encodeURIComponent(
       `https://intermediate-page-domain/back?orderId=${getQuery('orderId')}`
     );
     location.replace(`${mweb_url}&redirect_url=${redirect}`);
   })();
   </script>

3. Create back callback page

   <!-- https://intermediate-page-domain/back -->
   <script>
   location.replace(
     `yourapp://payResult?orderId=${getQuery('orderId')}&result=${getQuery('result')}`
   );
   </script>

4. App WebView loads intermediate page

   webView.loadUrl("https://intermediate-page-domain/pay-proxy?orderId=123")

5. Intercept and launch WeChat

   override fun shouldOverrideUrlLoading(view: WebView?, request: WebResourceRequest?): Boolean {
     val url = request?.url?.toString() ?: return false
     if (url.startsWith("weixin://")) {
       startActivity(Intent(Intent.ACTION_VIEW, Uri.parse(url)))
       return true
     }
     if (url.startsWith("yourapp://")) {
       handlePayResult(url)
       return true
     }
     return false
   }

6. Receive callback and refresh order
   Parse parameters in handlePayResult(url), close WebView, query backend order status.