Use a new folder structure

advanced-integration/package.json

@@ -2,11 +2,12 @@
   "name": "paypal-advanced-integration",
   "description": "Sample Node.js web app to integrate PayPal Advanced Checkout for online payments",
   "version": "1.0.0",
-  "main": "server.js",
+  "main": "server/server.js",
   "type": "module",
   "scripts": {
     "test": "echo \"Error: no test specified\" && exit 1",
-    "start": "node server.js"
+    "start": "node server/server.js",
+    "format": "npx prettier --write **.js"
   },
   "license": "Apache-2.0",
   "dependencies": {

advanced-integration/server.js → advanced-integration/server/server.js

@@ -1,13 +1,13 @@
 import express from "express";
 import fetch from "node-fetch";
 import "dotenv/config";
-import path from "path";
 
 const { PAYPAL_CLIENT_ID, PAYPAL_CLIENT_SECRET, PORT = 8888 } = process.env;
 const base = "https://api-m.sandbox.paypal.com";
 const app = express();
 app.set("view engine", "ejs");
-app.use(express.static("public"));
+app.set("views", "./server/views");
+app.use(express.static("client"));
 
 // parse post params sent in body in json format
 app.use(express.json());

standard-integration/README.md

@@ -6,7 +6,7 @@ This folder contains example code for a Standard PayPal integration using both t
 
 1. [Create an application](https://developer.paypal.com/dashboard/applications/sandbox/create)
 2. Rename `.env.example` to `.env` and update `PAYPAL_CLIENT_ID` and `PAYPAL_CLIENT_SECRET`
-3. Replace `test` in `index.html` with your app's client-id
+3. Replace `test` in `client/index.html` with your app's client-id
 4. Run `npm install`
 5. Run `npm start`
 6. Open http://localhost:8888

standard-integration/client/app.js

@@ -0,0 +1,94 @@
+window.paypal
+  .Buttons({
+    createOrder: async () => {
+      try {
+        const response = await fetch("/api/orders", {
+          method: "POST",
+          headers: {
+            "Content-Type": "application/json",
+          },
+          // use the "body" param to optionally pass additional order information
+          // like product ids and quantities
+          body: JSON.stringify({
+            cart: [
+              {
+                id: "YOUR_PRODUCT_ID",
+                quantity: "YOUR_PRODUCT_QUANTITY",
+              },
+            ],
+          }),
+        });
+
+        const orderData = await response.json();
+
+        if (orderData.id) {
+          return orderData.id;
+        } else {
+          const errorDetail = orderData?.details?.[0];
+          const errorMessage = errorDetail
+            ? `${errorDetail.issue} ${errorDetail.description} (${orderData.debug_id})`
+            : JSON.stringify(orderData);
+
+          throw new Error(errorMessage);
+        }
+      } catch (error) {
+        console.error(error);
+        resultMessage(`Could not initiate PayPal Checkout...<br><br>${error}`);
+      }
+    },
+    onApprove: async (data, actions) => {
+      try {
+        const response = await fetch(`/api/orders/${data.orderID}/capture`, {
+          method: "POST",
+          headers: {
+            "Content-Type": "application/json",
+          },
+        });
+
+        const orderData = await response.json();
+        // Three cases to handle:
+        //   (1) Recoverable INSTRUMENT_DECLINED -> call actions.restart()
+        //   (2) Other non-recoverable errors -> Show a failure message
+        //   (3) Successful transaction -> Show confirmation or thank you message
+
+        const errorDetail = orderData?.details?.[0];
+
+        if (errorDetail?.issue === "INSTRUMENT_DECLINED") {
+          // (1) Recoverable INSTRUMENT_DECLINED -> call actions.restart()
+          // recoverable state, per https://developer.paypal.com/docs/checkout/standard/customize/handle-funding-failures/
+          return actions.restart();
+        } else if (errorDetail) {
+          // (2) Other non-recoverable errors -> Show a failure message
+          throw new Error(`${errorDetail.description} (${orderData.debug_id})`);
+        } else if (!orderData.purchase_units) {
+          throw new Error(JSON.stringify(orderData));
+        } else {
+          // (3) Successful transaction -> Show confirmation or thank you message
+          // Or go to another URL:  actions.redirect('thank_you.html');
+          const transaction =
+            orderData?.purchase_units?.[0]?.payments?.captures?.[0] ||
+            orderData?.purchase_units?.[0]?.payments?.authorizations?.[0];
+          resultMessage(
+            `Transaction ${transaction.status}: ${transaction.id}<br><br>See console for all available details`,
+          );
+          console.log(
+            "Capture result",
+            orderData,
+            JSON.stringify(orderData, null, 2),
+          );
+        }
+      } catch (error) {
+        console.error(error);
+        resultMessage(
+          `Sorry, your transaction could not be processed...<br><br>${error}`,
+        );
+      }
+    },
+  })
+  .render("#paypal-button-container");
+
+// Example function to show a result to the user. Your site's UI library can be used instead.
+function resultMessage(message) {
+  const container = document.querySelector("#result-message");
+  container.innerHTML = message;
+}

standard-integration/client/checkout.html

@@ -0,0 +1,15 @@
+<!DOCTYPE html>
+<html lang="en">
+  <head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>PayPal JS SDK Standard Integration</title>
+  </head>
+  <body>
+    <div id="paypal-button-container"></div>
+    <p id="result-message"></p>
+    <!-- Replace the "test" client-id value with your client-id -->
+    <script src="https://www.paypal.com/sdk/js?client-id=test&currency=USD"></script>
+    <script src="app.js"></script>
+  </body>
+</html>

standard-integration/package.json

@@ -2,11 +2,12 @@
   "name": "paypal-standard-integration",
   "description": "Sample Node.js web app to integrate PayPal Standard Checkout for online payments",
   "version": "1.0.0",
-  "main": "server.js",
+  "main": "server/server.js",
   "type": "module",
   "scripts": {
     "test": "echo \"Error: no test specified\" && exit 1",
-    "start": "node server.js"
+    "start": "node server/server.js",
+    "format": "npx prettier --write **.js"
   },
   "license": "Apache-2.0",
   "dependencies": {

standard-integration/server.js → standard-integration/server/server.js

@@ -7,6 +7,9 @@ const { PAYPAL_CLIENT_ID, PAYPAL_CLIENT_SECRET, PORT = 8888 } = process.env;
 const base = "https://api-m.sandbox.paypal.com";
 const app = express();
 
+// host static files
+app.use(express.static("client"));
+
 // parse post params sent in body in json format
 app.use(express.json());
 
@@ -141,7 +144,7 @@ app.post("/api/orders/:orderID/capture", async (req, res) => {
 
 // serve index.html
 app.get("/", (req, res) => {
-  res.sendFile(path.resolve("./index.html"));
+  res.sendFile(path.resolve("./client/checkout.html"));
 });
 
 app.listen(PORT, () => {