More Webhook API Changes

- Updated API Models with Fixes
- Updated Samples
- Additional Functional Tests

sample/notifications/UpdateWebhook.php

@@ -0,0 +1,55 @@
+<?php
+
+// # Update Webhook Sample
+//
+// This sample code demonstrate how to use this call to update a webhook; supports the replace operation only, as documented here at:
+// https://developer.paypal.com/webapps/developer/docs/api/#update-a-webhook
+// API used: PATCH v1/notifications/webhooks/<Webhook-Id>
+
+// ## Get Webhook ID.
+// In samples we are using CreateWebhook.php sample to get the created instance of webhook.
+// However, in real case scenario, we could use just the ID from database or use an already existing webhook.
+/** @var \PayPal\Api\Webhook $webhook */
+$webhook = require 'CreateWebhook.php';
+// Updating the webhook as per given request
+//
+//      [
+//         {
+//             "op":"replace",
+//            "path":"/url",
+//            "value":"https://requestb.in/10ujt3c1"
+//         },
+//         {
+//             "op":"replace",
+//            "path":"/event_types",
+//            "value":[
+//               {
+//                   "name":"PAYMENT.SALE.REFUNDED"
+//               }
+//            ]
+//         }
+//      ]
+$patch = new \PayPal\Api\Patch();
+$patch->setOp("replace")
+    ->setPath("/url")
+    ->setValue("https://requestb.in/10ujt3c1?uniqid=". uniqid());
+
+$patch2 = new \PayPal\Api\Patch();
+$patch2->setOp("replace")
+    ->setPath("/event_types")
+    ->setValue(json_decode('[{"name":"PAYMENT.SALE.REFUNDED"}]'));
+
+$patchRequest = new \PayPal\Api\PatchRequest();
+$patchRequest->addPatch($patch)->addPatch($patch2);
+
+// ### Get Webhook
+try {
+    $output = $webhook->update($patchRequest, $apiContext);
+} catch (Exception $ex) {
+    ResultPrinter::printError("Updated a Webhook", "Webhook", null, $patchRequest, $ex);
+    exit(1);
+}
+
+ResultPrinter::printResult("Updated a Webhook", "Webhook", $output->getId(), $patchRequest, $output);
+
+return $output;