feat(CloudAsset): add sample code for listing assets (GoogleCloudPlatform#1479)

Author: peter-zheng-g

asset/src/list_assets.php

@@ -0,0 +1,49 @@
+<?php
+/**
+ * Copyright 2021 Google LLC.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+namespace Google\Cloud\Samples\Asset;
+
+// [START asset_quickstart_list_assets]
+use Google\Cloud\Asset\V1\AssetServiceClient;
+
+/**
+ * @param string       $projectId  Tthe project Id for list assets.
+ * @param string|array $assetTypes (Optional) Asset types to list for.
+ * @param int          $pageSize   (Optional) Size of one result page.
+ */
+function list_assets(string $projectId, array $assetTypes = [], int $pageSize)
+{
+    // Instantiate a client.
+    $client = new AssetServiceClient();
+
+    // Run request
+    $response = $client->listAssets(
+      "projects/$projectId", [
+        'assetTypes' => $assetTypes,
+        'pageSize' => $pageSize,
+      ]);
+
+    // Print the asset names in the result
+    foreach ($response->getPage() as $asset) {
+        print($asset->getName() . PHP_EOL);
+    }
+}
+// [END asset_quickstart_list_assets]
+
+// The following 2 lines are only needed to run the samples
+require_once __DIR__ . '/../../testing/sample_helpers.php';
+\Google\Cloud\Samples\execute_sample(__FILE__, __NAMESPACE__, $argv);

asset/test/assetTest.php

@@ -59,6 +59,20 @@ public function testExportAssets()
         $assetFile->delete();
     }
 
+    public function testListAssets()
+    {
+        $assetName = '//storage.googleapis.com/' . self::$bucketName;
+        $this->runEventuallyConsistentTest(function () use ($assetName) {
+            $output = $this->runFunctionSnippet('list_assets', [
+                'projectId' => self::$projectId,
+                'assetTypes' => ['storage.googleapis.com/Bucket'],
+                'pageSize' => 1000,
+            ]);
+
+            $this->assertStringContainsString($assetName, $output);
+        }, 10, true);
+    }
+
     public function testBatchGetAssetsHistory()
     {
         $assetName = '//storage.googleapis.com/' . self::$bucketName;