docs(samples): add LRO code snippets (#209)

* docs(samples): add LRO code snippets

* lint fix

* lint fix

* lint fix

* 🦉 Updates from OwlBot

See https://github.com/googleapis/repo-automation-bots/blob/main/packages/owl-bot/README.md

Co-authored-by: Owl Bot <gcf-owl-bot[bot]@users.noreply.github.com>

dialogflow-cx/long-running-operation.js

@@ -0,0 +1,54 @@
+// 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
+//
+//     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.
+
+'use strict';
+
+async function main(projectId, agentId, location) {
+  /**
+   * TODO(developer): Uncomment these variables before running the sample.
+   */
+  // const projectId = 'my-project';
+  // const agentId = 'my-agent';
+  // const location = 'global';
+
+  // [START dialogflow_cx_log_running_operation]
+
+  const {AgentsClient, protos} = require('@google-cloud/dialogflow-cx');
+
+  const api_endpoint = `${location}-dialogflow.googleapis.com`;
+
+  const client = new AgentsClient({apiEndpoint: api_endpoint});
+
+  const exportAgentRequest =
+    new protos.google.cloud.dialogflow.cx.v3.ExportAgentRequest();
+
+  exportAgentRequest.name = `projects/${projectId}/locations/${location}/agents/${agentId}`;
+
+  // exportAgent call returns a promise to a long running operation
+  const [operation] = await client.exportAgent(exportAgentRequest);
+
+  // Waiting for the long running opporation to finish
+  const [response] = await operation.promise();
+
+  // Prints the result of the operation when the operation is done
+  console.log(response);
+
+  // [END dialogflow_cx_log_running_operation]
+}
+
+process.on('unhandledRejection', err => {
+  console.error(err.message);
+  process.exitCode = 1;
+});
+main(...process.argv.slice(2));

dialogflow-cx/test/long-running-operation.test.js

@@ -0,0 +1,62 @@
+// 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
+//
+//     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.
+
+'use strict';
+
+const {assert} = require('chai');
+const {describe, before, it, after} = require('mocha');
+const execSync = require('child_process').execSync;
+const uuid = require('uuid');
+const dialogflow = require('@google-cloud/dialogflow-cx');
+const exec = cmd => execSync(cmd, {encoding: 'utf8'});
+const location = 'global';
+let agentId = '';
+let agentPath = '';
+
+describe('update intent', async () => {
+  const agentClient = new dialogflow.AgentsClient();
+  const projectId = await agentClient.getProjectId();
+  const agentDisplayName = `temp_agent_${uuid.v4().split('-')[0]}`;
+  const parent = 'projects/' + projectId + '/locations/' + location;
+  const cmd = 'node long-running-operation.js';
+
+  before('create an agent and get agent id', async () => {
+    // The path to identify the agent that owns the intents.
+
+    const agent = {
+      displayName: agentDisplayName,
+      defaultLanguageCode: 'en',
+      timeZone: 'America/Los_Angeles',
+    };
+
+    const request = {
+      agent,
+      parent,
+    };
+
+    const [agentResponse] = await agentClient.createAgent(request);
+
+    agentPath = agentResponse.name;
+    agentId = agentPath.split('/')[5];
+  });
+
+  after('delete Agent', async () => {
+    agentClient.deleteAgent({name: agentPath});
+  });
+
+  it('should export agent', async () => {
+    const output = exec(`${cmd} ${projectId} ${agentId} ${location}`);
+    assert.include(output, 'agentContent');
+  });
+});