feat: [DiscoveryEngine] move serving config update API to GA (#8189)

* feat: move serving config update API to GA
feat: add time_zone in user info
docs: keep the API doc up-to-date with recent changes

PiperOrigin-RevId: 740840314

Source-Link: googleapis/googleapis@ebc5e12

Source-Link: googleapis/googleapis-gen@f6f5759
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DiscoveryEngine/metadata/V1/Common.php

@@ -0,0 +1,85 @@
+<?php
+/*
+ * Copyright 2025 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
+ *
+ *     https://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.
+ */
+
+/*
+ * GENERATED CODE WARNING
+ * This file was automatically generated - do not edit!
+ */
+
+require_once __DIR__ . '/../../../vendor/autoload.php';
+
+// [START discoveryengine_v1_generated_ServingConfigService_UpdateServingConfig_sync]
+use Google\ApiCore\ApiException;
+use Google\Cloud\DiscoveryEngine\V1\Client\ServingConfigServiceClient;
+use Google\Cloud\DiscoveryEngine\V1\ServingConfig;
+use Google\Cloud\DiscoveryEngine\V1\SolutionType;
+use Google\Cloud\DiscoveryEngine\V1\UpdateServingConfigRequest;
+
+/**
+ * Updates a ServingConfig.
+ *
+ * Returns a NOT_FOUND error if the ServingConfig does not exist.
+ *
+ * @param string $servingConfigDisplayName  The human readable serving config display name. Used in Discovery
+ *                                          UI.
+ *
+ *                                          This field must be a UTF-8 encoded string with a length limit of 128
+ *                                          characters. Otherwise, an INVALID_ARGUMENT error is returned.
+ * @param int    $servingConfigSolutionType Immutable. Specifies the solution type that a serving config can
+ *                                          be associated with.
+ */
+function update_serving_config_sample(
+    string $servingConfigDisplayName,
+    int $servingConfigSolutionType
+): void {
+    // Create a client.
+    $servingConfigServiceClient = new ServingConfigServiceClient();
+
+    // Prepare the request message.
+    $servingConfig = (new ServingConfig())
+        ->setDisplayName($servingConfigDisplayName)
+        ->setSolutionType($servingConfigSolutionType);
+    $request = (new UpdateServingConfigRequest())
+        ->setServingConfig($servingConfig);
+
+    // Call the API and handle any network failures.
+    try {
+        /** @var ServingConfig $response */
+        $response = $servingConfigServiceClient->updateServingConfig($request);
+        printf('Response data: %s' . PHP_EOL, $response->serializeToJsonString());
+    } catch (ApiException $ex) {
+        printf('Call failed with message: %s' . PHP_EOL, $ex->getMessage());
+    }
+}
+
+/**
+ * Helper to execute the sample.
+ *
+ * This sample has been automatically generated and should be regarded as a code
+ * template only. It will require modifications to work:
+ *  - It may require correct/in-range values for request initialization.
+ *  - It may require specifying regional endpoints when creating the service client,
+ *    please see the apiEndpoint client configuration option for more details.
+ */
+function callSample(): void
+{
+    $servingConfigDisplayName = '[DISPLAY_NAME]';
+    $servingConfigSolutionType = SolutionType::SOLUTION_TYPE_UNSPECIFIED;
+
+    update_serving_config_sample($servingConfigDisplayName, $servingConfigSolutionType);
+}
+// [END discoveryengine_v1_generated_ServingConfigService_UpdateServingConfig_sync]