Implements test recommendation about findOrCreate.

Per discussion on [pull
request](#777),
he test implements a findOrCreate strategy to create a GCS bucket needed to
complete the test flow.

This commit also updates the README file accordingly.

Author: ricalo

functions/speech-to-speech/README.md

@@ -34,7 +34,8 @@ The sample requires the following environment variables:
   regions, see [Cloud Functions Locations][11] in the Functions documentation.
 * `GOOGLE_CLOUD_PROJECT`: The project id of your GCP project.
 * `BASE_URL`: The URL that the Cloud Functions emulator uses to serve requests.
-* `OUTPUT_BUCKET`: A bucket that the sample uses to drop translated files.
+* `OUTPUT_BUCKET`: A bucket that the sample uses to drop translated files. The
+  test script creates this buckt if it doesn't exist.
 * `GOOGLE_APPLICATION_CREDENTIALS`: The path to your API key file.
 * `SUPPORTED_LANGUAGE_CODES`: Comma-separated list of languages that the sample
   translates messages to.
@@ -73,11 +74,10 @@ The test script performs the following tasks:
 1. Runs the linter.
 1. Deploys the function to the emulator.
 1. Runs tests that don't perform any calls to the Google Cloud APIs.
-1. Creates a temporary Google Cloud Storage bucket with a random name.
+1. Creates the output bucket if it doesn't exist.
 1. Runs tests that perform calls to the Google Cloud APIs and drop the
    translated messages to the bucket.
 1. Deletes the files created during the tests.
-1. Deletes the temporary bucket.
 
 To run the tests, use the following commands from the
 `functions/speech-to-speech` folder:

functions/speech-to-speech/package.json

@@ -28,7 +28,7 @@
     "local-test": "mocha test/index.test.js",
     "system-test": "mocha --timeout 20000 test/sample.integration.http.test.js",
     "pretest": "npm run lint && sh test/updateFunctions.sh",
-    "test": "export OUTPUT_BUCKET=speech-to-speech-test-$(uuidgen) && functions restart && npm run local-test && npm run system-test"
+    "test": "npm run local-test && npm run system-test"
   },
   "dependencies": {
     "@google-cloud/speech": "^2.1.0",

functions/speech-to-speech/test/sample.integration.http.test.js

@@ -61,19 +61,22 @@ describe('Tests that do not require a GCS bucket', function () {
 });
 
 describe('Tests that require a GCS bucket', function () {
-  // Create the Google Cloud Storage bucket to run the tests.
-  // Caution: The 'after' hook deletes the bucket. To prevent deleting user data, the 'before' hook
-  // fails if the bucket already exists.
-  let bucketCreated = false;
+  // Create the Google Cloud Storage bucket if it doesn't exist.
   before('Create GCS bucket.', function (done) {
-    bucket.create({
-      location: storageLocation,
-      storageClass: storageClass
-    }).then(function (data) {
-      bucketCreated = true;
-      done();
-    }).catch(error => {
-      done(error);
+    bucket.exists().then(function (data) {
+      const exists = data[0];
+      if (!exists) {
+        bucket.create({
+          location: storageLocation,
+          storageClass: storageClass
+        }).then(function (data) {
+          done();
+        }).catch(error => {
+          done(error);
+        });
+      } else {
+        done();
+      }
     });
   });
   it('should return a successful response.', function (done) {
@@ -100,10 +103,7 @@ describe('Tests that require a GCS bucket', function () {
       })
       .expect(/"transcription":"this is a test please translate this message"/, done);
   });
-  after('Delete GCS bucket, files, and other test artifacts.', function (done) {
-    if (!bucketCreated) {
-      done(new Error('The before hook did not create the bucket, abort cleanup'));
-    }
+  after('Delete created files in the bucket and other test artifacts.', function (done) {
     // Load the response from the successful test.
     const responseBody = JSON.parse(fs.readFileSync('responseBody.test.json'));
 
@@ -116,9 +116,6 @@ describe('Tests that require a GCS bucket', function () {
     }
 
     Promise.all(deletedFiles).then(() => {
-      // Delete the empty bucket.
-      return bucket.delete();
-    }).then(() => {
       // Delete the file that stores the response from the successful test.
       fs.unlinkSync('responseBody.test.json');
       done();