test: added an expo back off to prevent RESOURCE_EXHAUSTED exception (#630)

* test: added an expo back off to prevent RESOURCE_EXHAUSTED exception

* modified comment

* changed arrow func-> regular

Author: munkhuushmgl

dialogflow/resources/output.wav

@@ -21,6 +21,8 @@ const uuid = require('uuid');
 const dialogflow = require('@google-cloud/dialogflow');
 const exec = cmd => execSync(cmd, {encoding: 'utf8'});
 
+const {delay} = require('./util');
+
 describe('list session entity types', () => {
   const client = new dialogflow.EntityTypesClient();
   const sessionClient = new dialogflow.SessionEntityTypesClient();
@@ -64,7 +66,10 @@ describe('list session entity types', () => {
     await sessionClient.createSessionEntityType(sessionEntityTypeRequest);
   });
 
-  it('should List the Session Entity Type', async () => {
+  it('should List the Session Entity Type', async function () {
+    this.retries(5);
+    await delay(this.test);
+
     const output = exec(`${cmd} list-session-entity-types -s ${sessionId}`);
     assert.include(output, sessionId);
     assert.include(output, displayName);

dialogflow/system-test/list-session-entity-types.test.js

@@ -0,0 +1,28 @@
+// Copyright 2020 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.
+
+// DialogFlow tests sometimes run into quota issues, for which
+// retrying with a backoff is a good strategy:
+module.exports = {
+  async delay(test) {
+    const retries = test.currentRetry();
+    if (retries === 0) return; // no retry on the first failure.
+    // see: https://cloud.google.com/storage/docs/exponential-backoff:
+    const ms = Math.pow(2, retries) * 1000 + Math.random() * 2000;
+    return new Promise(done => {
+      console.info(`retrying "${test.title}" in ${ms}ms`);
+      setTimeout(done, ms);
+    });
+  },
+};